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Innovative Approach of EOQ Structure for Decaying Items with Time Sensitive Demand, Cash- Discount, Shortages and Permissible Delay in Payments. INTERNATIONAL JOURNAL OF APPLIED AND COMPUTATIONAL MATHEMATICS 2021; 7:77. [PMID: 33937442 PMCID: PMC8074708 DOI: 10.1007/s40819-021-01003-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 03/21/2021] [Indexed: 11/18/2022]
Abstract
Growing business process and rising aggressive conditions are encouraged to use the inventory control scheme and components in an ideal way. Cash discount and permissible delay are beneficial for vendor and buyer both. This study considers an EOQ model through demand rate depends on the time. A lower or higher time leads to lower or higher demand after feedback vice versa. In this paper deterioration, cash- discount, shortages and permissible delay are also considered. Mathematical models are discussed under four different states of affair. Solution method is given for finding the finest answer. The main aim is to maximize total profit. Numerical examples are provided for all four dissimilar situations. Optimal values with strictures are calculated to analyze the sensitivity investigation of optimal strategy concerning the parameters of the system. It is revealed that the total income is concave by means of cycle time.
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Comparative Analysis of Colour Doppler Ultrasonography and CT Angiography in Peripheral Arterial Disease: Studying effects of Vessels Wall Calcification on Diagnostic Evaluation. J Clin Diagn Res 2018. [DOI: 10.7860/jcdr/2018/37479.12237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Increased transverse relaxivity in ultrasmall superparamagnetic iron oxide nanoparticles used as MRI contrast agent for biomedical imaging. CONTRAST MEDIA & MOLECULAR IMAGING 2016; 11:350-361. [PMID: 27230705 DOI: 10.1002/cmmi.1698] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 03/29/2016] [Accepted: 04/21/2016] [Indexed: 01/01/2023]
Abstract
Synthesis of a contrast agent for biomedical imaging is of great interest where magnetic nanoparticles are concerned, because of the strong influence of particle size on transverse relaxivity. In the present study, biocompatible magnetic iron oxide nanoparticles were synthesized by co-precipitation of Fe2+ and Fe3+ salts, followed by surface adsorption with reduced dextran. The synthesized nanoparticles were spherical in shape, and 12 ± 2 nm in size as measured using transmission electron microscopy; this was corroborated with results from X-ray diffraction and dynamic light scattering studies. The nanoparticles exhibited superparamagnetic behavior, superior T2 relaxation rate and high relaxivities (r1 = 18.4 ± 0.3, r2 = 90.5 ± 0.8 s-1 mM-1 , at 7 T). MR image analysis of animals before and after magnetic nanoparticle administration revealed that the signal intensity of tumor imaging, specific organ imaging and whole body imaging can be clearly distinguished, due to the strong relaxation properties of these nanoparticles. Very low concentrations (3.0 mg Fe/kg body weight) of iron oxides are sufficient for early detection of tumors, and also have a clear distinction in pre- and post-enhancement of contrast in organs and body imaging. Many investigators have demonstrated high relaxivities of magnetic nanoparticles at superparamagnetic iron oxide level above 50 nm, but this investigation presents a satisfactory, ultrasmall, superparamagnetic and high transverse relaxivity negative contrast agent for diagnosis in pre-clinical studies. Copyright © 2016 John Wiley & Sons, Ltd.
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Transgene expression study of CXCR4 active mutants. Potential prospects in up-modulation of homing and engraftment efficiency of hematopoietic stem/progenitor cells. Cell Adh Migr 2015; 8:384-8. [PMID: 25482641 DOI: 10.4161/cam.29285] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Homing and engraftment, a determining factor in hematopoietic stem cell transplantation success is defined as a process through which hematopoietic stem/progenitor cells (HSPCs) lodge recipient bone marrow. SDF-1/CXCR4 axis acts as a principle regulator in homing and engraftment, however, CXCR4 signaling is dependent upon expression of CXCR4 and its ligand SDF-1, which is highly dynamic. Hence, present investigation was aimed to explore the potential of CXCR4 constitutive active mutants (CXCR4-CAMs) in overcoming the limitation of CXCR4 signaling and up-modulate its efficiency in homing and engraftment. Regulated transgene expression study of these mutants revealed their significantly enhanced cell adhesion efficiency to endothelium and extracellular matrix protein. This altogether indicates promising prospects of CXCR4-CAMs in research aimed to improve HSPCs engraftment efficiency.
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Key Words
- Ala, Alanine
- Asn, Asparagine
- BM, Bone Marrow
- BMEC, Bone marrow endothelial cells
- BSA, Bovine Serum Albumin
- CAMs, Constitutive Active Mutants
- CXCR4
- Conc., Concentration
- ECM, Extracellular matrix
- FBS, Fetal Bovine Serum
- FN, Fibronectin
- HSPCs
- HSPCs, Hematopoietic Stem/ Progenitor Cells
- HUVECs, Human Umbilical Vein Endothelial cells
- IMDM, Iscove's Modified Dulbecco Media
- LIF, Leukemia Inhibitory Factor
- MCS, Multi Cloning Site
- Ser, Serine
- TM3, Transmembrane three domain
- engraftment
- homing
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Longitudinal changes in the DTI measures, anti-GFAP expression and levels of serum inflammatory cytokines following mild traumatic brain injury. Exp Neurol 2015. [PMID: 26216663 DOI: 10.1016/j.expneurol.2015.07.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The majority of human mild traumatic brain injuries (mTBI; 70%) lack radiological evidence of injury, yet may present long term cognitive, and behavioral dysfunctions. With the hypothesis of evident damaged neural tissue and immunological consequences during acute phase of mTBI, we used closed skull weight-drop TBI model to address human mTBI condition. Serum cytokines (TNF-α, IL-10) and glial fibrillary acidic protein (GFAP) expression were examined at day 0 (control, pre-injury), 4h, day 1, day 3 and day 5 post injury (PI). Diffusion tensor imaging (DTI) was performed at similar timepoints to identify neuroinflammation translation into imaging abnormalities and monitor injury progression. DTI indices including mean diffusivity (MD), radial diffusivity (RD), fractional anisotropy and axial diffusivity values were quantified from cortex (CTX), hippocampus and corpus callosum regions. One way ANOVA showed significant increase in TNF-α at 4h and IL-10 at day 1 PI as compared to control. GFAP(+) cells were significantly increased at day 3 and day 5 as compared to control in CTX. Repeated measures ANOVA revealed significant decreases in MD, RD values in CTX at day 3 and day 5 as compared to day 0. A significant, inverse correlation was observed between cortical MD (r=-0.74, p=0.01), AD (r=-0.60, p=0.03) and RD (r=-0.72, p=0.01) values with mean GFAP(+) cells in the cortical region. These findings suggest that mTBI leads to elevated cytokine expression and subsequent hypertrophy of astrocytic processes. The increased numbers of reactive glial cells contribute diffusion restrictions in the CNS leading to reduced MD and RD values. These findings are in line with the deficits and pathologies associated with clinical mTBI, and support the use of mTBI model to address pathology and therapeutic options.
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Transparent magnesium aluminate spinel: a prospective biomaterial for esthetic orthodontic brackets. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2014; 25:2591-2599. [PMID: 25027301 DOI: 10.1007/s10856-014-5268-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 06/24/2014] [Indexed: 06/03/2023]
Abstract
Adult orthodontics is recently gaining popularity due to its importance in esthetics, oral and general health. However, none of the currently available alumina or zirconia based ceramic orthodontic brackets meet the esthetic demands of adult patients. Inherent hexagonal lattice structure and associated birefringence limits the visible light transmission in polycrystalline alumina and make them appear white and non transparent. Hence focus of the present study was to assess the feasibility of using magnesium aluminate (MgAl2O4) spinel; a member of the transparent ceramic family for esthetic orthodontic brackets. Transparent spinel specimens were developed from commercially available white spinel powder through colloidal shaping followed by pressureless sintering and hot isostatic pressing at optimum conditions of temperature and pressure. Samples were characterized for chemical composition, phases, density, hardness, flexural strength, fracture toughness and optical transmission. Biocompatibility was evaluated with in-vitro cell line experiments for cytotoxicity, apoptosis and genotoxicity. Results showed that transparent spinel samples had requisite physico-chemical, mechanical, optical and excellent biocompatibility for fabricating orthodontic brackets. Transparent spinel developed through this method demonstrated its possibility as a prospective biomaterial for developing esthetic orthodontic brackets.
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Radical Scavenging and Radiomodulatory Effects of Psoralea corylifolia Linn. Substantiated by in vitro Assays and EPR Spectroscopy. Z NATURFORSCH C 2014. [DOI: 10.1515/znc-2011-1-206] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The present study is the first report of the radiomodulatory effects of Psoralea corylifolia Linn. The extract (IBG-RA-26) prepared from P. corylifolia was chemically analysed by HPLC, LC-MS/MS and NMR. The total polyphenolic content of IBG-RA-26 was 0.287 mg/ ml of quercetin equivalents. IBG-RA-26 exhibited a dose-dependent increase in 2,2-diphenyl- 1-picrylhydrazyl (DPPH) radical scavenging activity. It exhibited comparable (> 50%) site-specific and non-site-specific hydroxyl radical scavenging activity in higher concentration ranges (500 - 1000 μg/ml), while at lower concentrations (5 - 50 μg/ml) it exhibited significantly (p < 0.05) higher non-site-specific scavenging ability compared to site-specific activity. Nitric oxide scavenging activity of IBG-RA-26 (5 - 1000 μg/ml) increased in a concentrationdependent manner, while maximum superoxide ion scavenging ability (79%) was observed at 50 μg/ml. The electron donation potential of IBG-RA-26 was found to be higher than that of ascorbic acid at lower concentrations (up to 5 μg/ml). Analysis of the ability of IBGRA- 26 to protect membranes against γ-radiation, utilizing an artificial membrane system (liposome), revealed a significant (p < 0.05) decrease in the formation of malondialdehyde (MDA) as a function of the concentration of IBG-RA-26. Radiation-induced lysis of human erythrocytes was monitored and efficacy of IBG-RA-26 was tested in the concentration range 25 - 1000 μg/ml, with significant protective efficacy observed in the range 25 - 50 μg/ml. IBG-RA-26 rendered significant (p < 0.05) protection against radiation (0.25 kGy)-induced DNA damage. EPR spectroscopy was used to investigate the DPPH radical scavenging capacity of IBG-RA-26. IBG-RA-26 exhibited a good DPPH radical scavenging capacity in a concentration-dependent manner. By direct EPR spectroscopy we have also demonstrated the possible formation of free radical species in a solution of IBG-RA-26. The wide spectrum of radioprotective and antioxidant properties exhibited by IBG-RA-26 indicate that P. corylifolia has potential as a radiomodulatory agent.
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Modification of radiation-induced DNA double strand break repair pathways by chemicals extracted from Podophyllum hexandrum: an in vitro study in human blood leukocytes. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2014; 55:436-448. [PMID: 24500925 DOI: 10.1002/em.21853] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 10/23/2013] [Accepted: 01/08/2014] [Indexed: 06/03/2023]
Abstract
Radiation exposure is a serious threat to biomolecules, particularly DNA, proteins and lipids. Various exogenous substances have been reported to protect these biomolecules. In this study we explored the effect of pre-treatment with G-002M, a mixture of three active derivatives isolated from the rhizomes of Podophyllum hexandrum, on DNA damage response in irradiated human blood leukocytes. Blood was collected from healthy male volunteers, preincubated with G-002M and then irradiated with various doses of radiation. Samples were analyzed using flow cytometry to quantify DNA double strand break (DSB) biomarkers including γ-H2AX, P53BP1 and levels of ligase IV. Blood samples were irradiated in vitro and processed to determine time and dose-dependent kinetics. Semiquantitative RT-PCR was performed at various time points to measure gene expression of DNA-PKcs, Ku80, ATM, and 53BP1; each of these genes is involved in DNA repair signaling. Pre-treatment of blood with G-002M resulted in reduction of γ-H2AX and P53BP1 biomarkers levels and elevated ligase IV levels relative to non-G-002M-treated irradiated cells. These results confirm suppression in radiation-induced DNA DSBs. Samples pre-treated with G-002M and then irradiated also showed significant up-regulation of DNA-PKcs and Ku80 and downregulation of ATM and 53BP1 gene expressions, suggesting that G-002M plays a protective role against DNA damage. The protective effect of G-002M may be due to its ability to scavange radiation-induced free radicals or assist in DNA repair. Further studies are needed to decipher the role of G-002M on signaling molecules involved in radiation-induced DNA damage repair pathways.
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Laser ionization mass spectrometry in oral squamous cell carcinoma. J Oral Pathol Med 2013; 43:471-83. [PMID: 24112294 DOI: 10.1111/jop.12117] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/23/2013] [Indexed: 12/15/2022]
Abstract
Biomarker research in oral squamous cell carcinoma (OSCC) aims for screening/early diagnosis and in predicting its recurrence, metastasis and overall prognosis. This article reviews the current molecular perspectives and diagnosis of oral cancer with proteomics using matrix-assisted laser desorption ionization (MALDI) and surface-enhanced laser desorption ionization (SELDI) mass spectrometry (MS). This method shows higher sensitivity, accuracy, reproducibility and ability to handle complex tissues and biological fluid samples. However, the data interpretation tools of contemporary mass spectrometry still warrant further improvement. Based on the data available with laser-based mass spectrometry, biomarkers of OSCC are classified as (i) diagnosis and prognosis, (ii) secretory, (iii) recurrence and metastasis, and (iv) drug targets. Majority of these biomarkers are involved in cell homeostasis and are either physiologic responders or enzymes. Therefore, proteins directly related to tumorigenesis have more diagnostic value. Salivary secretory markers are another group that offers a favourable and easy strategy for non-invasive screening and early diagnosis in oral cancer. Key molecular inter-related pathways in oral carcinogenesis are also intensely researched with software analysis to facilitate targeted drug therapeutics. The review suggested the need for incorporating 'multiple MS or tandem approaches' and focusing on a 'group of biomarkers' instead of single protein entities, for making early diagnosis and treatment for oral cancer a reality.
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Individual differences in trait anxiety are associated with white matter tract integrity in fornix and uncinate fasciculus: Preliminary evidence from a DTI based tractography study. Behav Brain Res 2013; 238:188-92. [DOI: 10.1016/j.bbr.2012.10.007] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 10/04/2012] [Accepted: 10/08/2012] [Indexed: 11/26/2022]
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High throughput transcriptome profiling of lithium stimulated human mesenchymal stem cells reveals priming towards osteoblastic lineage. PLoS One 2013; 8:e55769. [PMID: 23383279 PMCID: PMC3559497 DOI: 10.1371/journal.pone.0055769] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 01/04/2013] [Indexed: 02/07/2023] Open
Abstract
Human mesenchymal stem cells (hMSCs) present in the bone marrow are the precursors of osteoblasts, chondrocytes and adipocytes, and hold tremendous potential for osteoregenerative therapy. However, achieving directed differentiation into osteoblasts has been a major concern. The use of lithium for enhancing osteogenic differentiation has been documented in animal models but its effect in humans is not clear. We, therefore, performed high throughput transcriptome analysis of lithium-treated hMSCs to identify altered gene expression and its relevance to osteogenic differentiation. Our results show suppression of proliferation and enhancement of alkaline phosphatase (ALP) activity upon lithium treatment of hMSCs under non-osteogenic conditions. Microarray profiling of lithium-stimulated hMSC revealed decreased expression of adipogenic genes (CEBPA, CMKLR1, HSD11B1) and genes involved in lipid biosynthesis. Interestingly, osteoclastogenic factors and immune responsive genes (IL7, IL8, CXCL1, CXCL12, CCL20) were also downregulated. Negative transcriptional regulators of the osteogenic program (TWIST1 and PBX1) were suppressed while genes involved in mineralization like CLEC3B and ATF4 were induced. Gene ontology analysis revealed enrichment of upregulated genes related to mesenchymal cell differentiation and signal transduction. Lithium priming led to enhanced collagen 1 synthesis and osteogenic induction of lithium pretreated MSCs resulted in enhanced expression of Runx2, ALP and bone sialoprotein. However, siRNA-mediated knockdown of RRAD, CLEC3B and ATF4 attenuated lithium-induced osteogenic priming, identifying a role for RRAD, a member of small GTP binding protein family, in osteoblast differentiation. In conclusion, our data highlight the transcriptome reprogramming potential of lithium resulting in higher propensity of lithium "primed" MSCs for osteoblastic differentiation.
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Abstract
Stem cell therapy hold the potential to meet the demand for transplant cells/tissues needed for treating damages resulting from both natural and man-made disasters. Pluripotency makes embryonic stem cells and induced pluripotent stem cells ideal for use, but their teratogenic character is a major hindrance. Therapeutic benefits of bone marrow transplantation are well known but characterizing the potentialities of haematopoietic and mesenchymal cells is essential. Haematopoietic stem cells (HSCs) have been used for treating both haematopoietic and non-haematopoietic disorders. Ease of isolation, in vitro expansion, and hypoimmunogenecity have brought mesenchymal stem cells (MSCs) into limelight. Though differentiation of MSCs into tissue-specific cells has been reported, differentiation-independent mechanisms seem to play a more significant role in tissue repair which need to be addressed further. The safety and feasibility of MSCs have been demonstrated in clinical trials, and their use in combination with HSC for radiation injury treatment seems to have extended benefit. Therefore, using stem cells for treatment of disaster injuries along with the conventional medical practice would likely accelerate the repair process and improve the quality of life of the victim.
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Radiation-induced early changes in the brain and behavior: Serial diffusion tensor imaging and behavioral evaluation after graded doses of radiation. J Neurosci Res 2012; 90:2009-19. [DOI: 10.1002/jnr.23073] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 03/09/2012] [Accepted: 03/26/2012] [Indexed: 11/06/2022]
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Phosphorous magnetic resonance spectroscopy-based skeletal muscle bioenergetic studies in subclinical hypothyroidism. J Endocrinol Invest 2012; 35:129-34. [PMID: 21508663 DOI: 10.3275/7676] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
BACKGROUND Subclinical hypothyroidism (sHT) is considered to be a milder form of thyroid dysfunction. Few earlier studies have reported neuromuscular symptoms as well as impaired muscle metabolism in sHT patients. AIM/OBJECTIVE In this study we report our findings on muscle bioenergetics in sHT patients using phosphorous magnetic resonance spectroscopy (31P MRS) and look upon the possibility to use 31P MRS technique as a clinical marker for monitoring muscle function in subclinical thyroid dysfunction. SUBJECTS AND METHODS Seventeen normal subjects, 15 patients with sHT, and 9 patients with hypothyroidism performed plantar flexion exercise while lying supine in 1.5 T magnetic resonance scanner using custom built exercise device. MR Spectroscopy measurements of inorganic phosphate (Pi), phosphocreatine (PCr), and ATP of the calf muscle were taken during rest, at the end of exercise and in the recovery phase. PCr recovery rate constant (kPCr) and oxidative capacity were calculated by monoexponential fit of PCr vs time (t) at the beginning of recovery. RESULTS We observed that changes in some of the phosphometabolites (increased phosphodiester levels and Pi concentration) in sHT patients which were similar to those detected in patients with hypothyroidism. However, our results do not demonstrate impaired muscle oxidative metabolism in sHT patients based upon PCr dynamics as observed in hypothyroid patients. CONCLUSIONS 31P MRS-based PCr recovery rate could be used as a marker for monitoring muscle oxidative metabolism in sub clinical thyroid dysfunction.
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Principal eigenvector field segmentation for reproducible diffusion tensor tractography of white matter structures. Magn Reson Imaging 2011; 29:1088-100. [DOI: 10.1016/j.mri.2011.04.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Revised: 04/16/2011] [Accepted: 04/22/2011] [Indexed: 10/18/2022]
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Differential biochemical response of rat kidney towards low and high doses of NiCl2 as revealed by NMR spectroscopy. J Appl Toxicol 2011; 33:134-41. [PMID: 21928331 DOI: 10.1002/jat.1730] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Revised: 07/05/2011] [Accepted: 07/28/2011] [Indexed: 12/29/2022]
Abstract
Heavy metals are known for their associated nephrotoxicity and nickel is no exception. An integrated metabonomic approach, based on high-resolution (1) H NMR spectroscopy, was applied to determine the acute biochemical effects of NiCl(2) on the renal tissues of rats. Kidney homogenates from rats treated with NiCl(2) at two dose levels (4 and 20 mg kg(-1) b.w., i.p.) and those from controls were analysed using (1) H NMR spectroscopy and also assessed for antioxidant parameters at days 1, 3 and 5 post-dose. The major metabolite changes corresponding to nickel exposure were related to amino acids, osmolytes and energy metabolites. Differential responses were observed in (1) H NMR spectra with exposure to low and high doses of NiCl(2). For high doses, (1) H NMR spectral analysis revealed alterations in renal tissues, along with damage to the cortical and papillary region and depletion of renal osmolytes such as betaine, trimethyl amine oxide, myo-inositol and taurine, which persisted until day 5 post-dose. The metabolite profile of (1) H NMR spectra obtained from animals treated with lower dose of NiCl(2) initially increased as an immediate stress response and then showed signs of recovery with the passage of time. NMR spectral analysis was well corroborated with histopathological and oxidative stress results. Nickel-induced oxidative stress was observed in both groups of animals with increased levels of antioxidant parameters at initial time points, but continued to increase in the high-dose group. The present study shows a huge potential of metabonomics for mapping organ-based metabolic response during heavy metal toxicity.
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Intra-cavitary course of right coronary artery: what the cardiologists should be aware of! Indian Heart J 2011; 63:475-476. [PMID: 23550430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023] Open
Abstract
We report an unusual case of an anomalous intra-cavitary course of the right coronary artery (RCA) that was detected on multislice computed tomography (CT) angiography. Albeit rare, this anomaly is being picked up with increasing frequency owing to the widespread use of coronary CT angiography (CCTA). Although this entity does not produce symptoms per se, it can result in potentially catastrophic complications during interventional procedures or bypass surgeries if not recognized in time.
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Studies on the time course of apparent diffusion coefficient and signal intensities on T2- and diffusion-weighted MR Imaging in acute cerebral ischemic stroke. J Med Phys 2011; 33:162-70. [PMID: 19893711 PMCID: PMC2772048 DOI: 10.4103/0971-6203.44479] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Accepted: 08/28/2008] [Indexed: 12/04/2022] Open
Abstract
The time course of changes in apparent diffusion coefficient (ADC) and signal intensity on diffusion-weighted magnetic resonance imaging (DW MR) imaging in acute ischemic stroke is a very dynamic event. There is an initial reduction in ADCs with no change on T2-W imaging but signal intensity increase on T2-weighted takes place about 6–12 hours after onset of stroke. As necrosis begins to set in, there is a gradual reversal of ADC change, and around 3–10 days post-onset, ADC pseudonormalizes. Twenty-four patients of acute stroke underwent diffusion MR imaging in addition to conventional T1W, T2W, and Fluid Attenuated Inversion Recovery (FLAIR) sequence performed within 12 hours, at 30 days, and at 90 days. The mean signal intensity at b = 0 s/mm2 and at b = 1000 s/mm2 were significantly higher than control values for all time periods. The ratio of signal intensity at b = 0 (rSI b=0) significantly increased from 1.63 ± 0.20 in the acute stage to 2.19 ± 0.24 in the chronic stage (P < 0.001). The ratio of signal intensity on DWI (r SIDWI) decreased from 2.54 ± 0.46 to 1.54 ± 0.22. The mean ADC in the lesion was found to be 41% lower than the mean ADC in the contralateral hemisphere .Linear regression analysis between rADC and log hours showed that pseudonormalization occurred at 6.61 days (P < 0.001). We conclude that the above information could be useful in the management of very early stroke.
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Correlation of quantitative diffusion tensor tractography with clinical grades of subacute sclerosing panencephalitis. AJNR Am J Neuroradiol 2011; 32:714-20. [PMID: 21330388 DOI: 10.3174/ajnr.a2380] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE SSPE is a persistent infection of the central nervous system caused by the measles virus. The correlation between the clinical staging and conventional MR imaging is usually poor. The purpose of this study was to determine whether tract-specific DTI measures in the major white mater tracts correlate with clinical grades as defined by the Jabbour classification for SSPE. MATERIALS AND METHODS Quantitative DTT was performed on 20 patients with SSPE (mean age, 9 years) and 14 age- and sex-matched controls. All patients were graded on the basis of the Jabbour classification into grade II (n=9), grade III (n=6), and grade IV (n=5) SSPE. The major white matter tracts quantified included the CC, SLF, ILF, CST, CNG, SCP, MCP, ICP, ATR, STR, and PTR. RESULTS Although a successive decrease in mean FA values was observed in all the fiber tracts except for the SCP and ICP, moving from controls to grade IV, a significant inverse correlation between clinical grade and mean FA values was observed only in the splenium (r=-0.908, P<.001), CST (r=-0.663, P=.013), SLF (r=-0.533, P=.050), ILF (r=-0.776, P=.001), STR (r=-0.538, P=.047), and PTR (r=-0.686, P=.035) fibers. No significant correlation of mean MD values from these white matter tracts was observed with clinical grades of the disease. CONCLUSIONS We conclude that the grade of encephalopathy correlates inversely with the tract-specific mean FA values. This information may be valuable in studying the disease progression with time and in assessing the therapeutic response in the future.
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Stromal-derived factor-1/CXCR4 signaling: indispensable role in homing and engraftment of hematopoietic stem cells in bone marrow. Stem Cells Dev 2011; 20:933-46. [PMID: 21186999 DOI: 10.1089/scd.2010.0263] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Homing and engraftment of hematopoietic stem/progenitor cells (HSPCs) in bone marrow is the major determining factor in success of hematopoietic stem cell transplantation. This is a complex, multistep process orchestrated by the coordinated interplay between adhesion molecules, cytokines, growth factors, and regulatory cofactors, many of which remain to be defined. Recent studies have highlighted the pivotal role of unique stromal-derived factor-1 (SDF-1)/CXCR4 signaling in the regulation of HSPC homing and subsequent engraftment. In addition, studies suggest that SDF-1/CXCR4 signaling acts as an essential survival-promoting factor of transplanted HSPCs as well as maintenance of quiescent HSCs in bone marrow niche. These pleiotropic effects exerted by SDF-1/CXCR4 axis make this unique signaling initiator very promising, not only for optimal hematopoietic reconstitution but also for the development of innovative approaches to achieve restoration, regeneration, or repair of other damaged tissues potentially amendable to reversal by stem cell transplantation. This goal can only be achieved when the role of SDF-1/CXCR4 axis in hematopoietic transplantation is clearly defined. Hence, this review presents current knowledge of the mechanisms through which SDF-1/CXCR4 signaling promotes restoration of hematopoiesis by regulating the homing and engraftment of HSPCs.
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Study of acute biochemical effects of thallium toxicity in mouse urine by NMR spectroscopy. J Appl Toxicol 2011; 31:663-70. [DOI: 10.1002/jat.1617] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 09/14/2010] [Accepted: 10/08/2010] [Indexed: 01/05/2023]
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Radical scavenging and radiomodulatory effects of Psoralea corylifolia Linn. substantiated by in vitro assays and EPR spectroscopy. Z NATURFORSCH C 2011; 66:35-46. [PMID: 21476435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The present study is the first report of the radiomodulatory effects of Psoralea corylifolia Linn. The extract (IBG-RA-26) prepared from P. corylifolia was chemically analysed by HPLC, LC-MS/MS and NMR. The total polyphenolic content of IBG-RA-26 was 0.287 mg/ml of quercetin equivalents. IBG-RA-26 exhibited a dose-dependent increase in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. It exhibited comparable (> 50%) site-specific and non-site-specific hydroxyl radical scavenging activity in higher concentration ranges (500-1000 microg/ml), while at lower concentrations (5-50 microg/ml) it exhibited significantly (p < 0.05) higher non-site-specific scavenging ability compared to site-specific activity. Nitric oxide scavenging activity of IBG-RA-26 (5-1000 microg/ml) increased in a concentration-dependent manner, while maximum superoxide ion scavenging ability (79%) was observed at 50 microg/ml. The electron donation potential of IBG-RA-26 was found to be higher than that of ascorbic acid at lower concentrations (up to 5 microg/ml). Analysis of the ability of IBG-RA-26 to protect membranes against gamma-radiation, utilizing an artificial membrane system (liposome), revealed a significant (p < 0.05) decrease in the formation of malondialdehyde (MDA) as a function of the concentration of IBG-RA-26. Radiation-induced lysis of human erythrocytes was monitored and efficacy of IBG-RA-26 was tested in the concentration range 25-1000 microg/ml, with significant protective efficacy observed in the range 25-50 microg/ml. IBG-RA-26 rendered significant (p < 0.05) protection against radiation (0.25 kGy)-induced DNA damage. EPR spectroscopy was used to investigate the DPPH radical scavenging capacity of IBG-RA-26. IBG-RA-26 exhibited a good DPPH radical scavenging capacity in a concentration-dependent manner. By direct EPR spectroscopy we have also demonstrated the possible formation of free radical species in a solution of IBG-RA-26. The wide spectrum of radioprotective and antioxidant properties exhibited by IBG-RA-26 indicate that P. corylifolia has potential as a radiomodulatory agent.
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Nuclear magnetic resonance spectroscopy-based metabonomic investigation of biochemical effects in serum of γ-irradiated mice. Int J Radiat Biol 2010; 87:91-7. [PMID: 21087167 DOI: 10.3109/09553002.2010.518211] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE Radiation exposure induces change in many biological compounds. It is important to assess the physiological and biochemical response to an absorbed dose of ionising radiation due to intentional or accidental event and to predict medical consequences for medical management. In the present study, nuclear magnetic resonance (NMR) spectroscopy-based metabolic profiling was used in mice serum for identification of radiation-induced changes at metabolite level. MATERIALS AND METHODS Mice were irradiated with 3, 5 and 8 Gray of γ-radiation dose and serum samples collected at day 1, 3 and 5 post irradiation were analysed by proton nuclear magnetic resonance (¹H NMR) spectroscopy. ¹H NMR spectra of serum were analysed by pattern recognition using principal component analysis. RESULTS Irradiated mice serum showed distinct metabonomic phenotypes and revealed dose- and time-dependent clustering of irradiated groups. ¹H NMR spectral analysis exhibited increased lactate, amino acids, choline and lipid signals as well as decreased glucose signals. These findings indicate radiation-induced disturbed energy, lipid and protein metabolism. CONCLUSIONS The information obtained from this study reflects multiple physiological dysfunctions. The study promises the application of NMR-based metabonomics in the field of radiobiology, for development of metabolic-based markers for screening of risk populations and medical management in these cases.
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Nuclear magnetic resonance spectroscopy-based metabonomic investigation of biochemical effects in serum of γ-irradiated mice. Int J Radiat Biol 2010. [DOI: 10.3109/09553002.2011.518211] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Clinical studies for improving radiotherapy with 2-deoxy-D-glucose: present status and future prospects. J Cancer Res Ther 2010; 5 Suppl 1:S21-6. [PMID: 20009289 DOI: 10.4103/0973-1482.55136] [Citation(s) in RCA: 145] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Higher rates of glucose usage generally correlate with poor prognosis in several types of malignant tumours. Experimental studies (both in vitro and in vivo) have shown that 2-deoxy-D-glucose (2-DG), a glucose analog and glycolytic inhibitor, enhances radiation-induced damage selectively in tumor cells while protecting normal cells, thereby suggesting that 2-DG can be used as a differential radiomodifier to improve the efficacy of radiotherapy. Clinical trials undertaken to study the feasibility, safety, and validity of this suggested approach will be described. Based on 2-DG-induced radiosensitization observed in primary organ cultures of cerebral glioma tissues, clinical trials were designed taking into consideration the radiobiology of gliomas and pharmacokinetics of 2-DG. Phase I/II clinical trials have unequivocally demonstrated that a combination of 2-DG (200-300 mg 2-DG per kg body weight orally administered after overnight fasting, 20 min before irradiation) with large weekly fractions (5 Gy/fraction) of low-LET radiotherapy is well tolerated without any acute toxicity or late radiation damage to the normal brain tissue. Nonserious transient side effects similar to hypoglycemia induced disturbances like restlessness, nausea, and vomiting were observed at the 2-DG doses used. Data from these trials involving more than 100 patients have clearly indicated a moderate increase in the survival, with a significant improvement in the quality of life with clinicopathological evidence of protection of normal brain tissue. A phase III multicentric trial to evaluate the efficacy of the combined treatment is in progress. Directions for future studies are discussed.
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Mapping the extent of disease by multislice computed tomography, magnetic resonance imaging and sentinel node evaluation in stage I and II cervical carcinoma. J Cancer Res Ther 2010; 6:267-71. [DOI: 10.4103/0973-1482.73342] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Understanding development and lateralization of major cerebral fiber bundles in pediatric population through quantitative diffusion tensor tractography. Pediatr Res 2009; 66:636-41. [PMID: 19687778 DOI: 10.1203/pdr.0b013e3181bbc6b5] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Region of interest based morphometric diffusion tensor imaging analysis, has been used extensively for the assessment of age-related changes in human brain, is limited to two dimensions and does not reflect the whole fiber bundle; however, diffusion tensor tractography (DTT) offers an overall view of individual fiber bundle in three-dimensional spaces. Quantitative DTT was performed on 51 healthy subjects of pediatric age range and young adults to compare age-related fractional anisotropy (FA) changes in corpus callosum, sensory and motor pathways, limbic tracts [cingulum (CNG) and fornix (Fx)], and superior and inferior longitudinal fascicules. In corpus callosum, inferior longitudinal fascicules, limbic tracts (CNG and Fx), sensory pathways, and motor pathways, an initial sharp increase in FA was observed up to the age of 2 y followed by a gradual increase up to 21 y. In superior longitudinal fascicules, sharp increase in FA was observed up to 3 y followed by a gradual increase. The FA value of the left CNG (p = 0.01, sign test) was observed to be significantly greater than that of the right CNG. We conclude that white matter fiber tracts mature with age and can be assessed by using DTT that may greatly improve our understanding of the human brain development.
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Abstract
Mesenchymal stem cells (MSCs), adherent fibroblastoid cells, present in bone marrow and many other tissues can be easily isolated and expanded in vitro. They are capable of differentiating into different cell types such as osteoblasts, chondrocytes, adipocytes, cardiomyocytes, hepatocytes, endothelial cells and neuronal cells. Such immense plasticity coupled with their ability to modulate the activity of immune cells makes them attractive for stem cell-based therapy aimed at treating previously incurable disorders. Preclinical studies have reported successful use of MSCs for delivering therapeutic proteins and repairing defects in a variety of disease models. These studies highlighted the in vivo potential of MSCs and their ability to home to injury sites and modify the microenvironment by secreting paracrine factors to augment tissue repair. Their therapeutic applicability has been widened by genetic modification to enhance differentiation and tissue targeting, and use in tissue engineering. Clinical trials for diseases such as osteogenesis imperfecta, graft-versus-host disease and myocardial infarction have shown some promise, demonstrating the safe use of both allogeneic and autologous cells. However, lack of knowledge of MSC behaviour and responses in vitro and in vivo force the need for basic and animal studies before heading to the clinic. Contrasting reports on immunomodulatory functions and tumorigenicity along with issues such as mode of cell delivery, lack of specific marker, low survival and engraftment require urgent attention to harness the potential of MSC-based therapy in the near future.
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PU.1 and partners: regulation of haematopoietic stem cell fate in normal and malignant haematopoiesis. J Cell Mol Med 2009; 13:4349-63. [PMID: 19382896 PMCID: PMC4515051 DOI: 10.1111/j.1582-4934.2009.00757.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
During normal haematopoiesis, cell development and differentiation programs are accomplished by switching ‘on’ and ‘off’ specific set of genes. Specificity of gene expression is primarily achieved by combinatorial control, i.e. through physical and functional interactions among several transcription factors that form sequence-specific multiprotein complexes on regulatory regions (gene promoters and enhancers). Such combinatorial gene switches permit flexibility of regulation and allow numerous developmental decisions to be taken with a limited number of regulators. The haematopoietic-specific Ets family transcription factor PU.1 regulates many lymphoid- and myeloid-specific gene promoters and enhancers by interacting with multiple proteins during haematopoietic development. Such protein–protein interactions regulate DNA binding, subcellular localization, target gene selection and transcriptional activity of PU.1 itself in response to diverse signals including cytokines, growth factors, antigen and cellular stresses. Specific domains of PU.1 interact with many protein motifs such as bHLH, bZipper, zinc fingers and paired domain for regulating its activity. This review focuses on important protein–protein interactions of PU.1 that play a crucial role in regulation of normal as well as malignant haematopoiesis. Precise delineation of PU.1 protein-partner interacting interface may provide an improved insight of the molecular mechanisms underlying haematopoietic stem cell fate regulation. Its interactions with some proteins could be targeted to modulate the aberrant signalling pathways for reversing the malignant phenotype and to control the generation of specific haematopoietic progeny for treatment of haematopoietic disorders.
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Whole body protection against lethal ionizing radiation in mice by REC-2001: a semi-purified fraction of Podophyllum hexandrum. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2009; 16:47-55. [PMID: 17574826 DOI: 10.1016/j.phymed.2007.04.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The current study has concentrated on assessment of the radioprotective potential of REC-2001, a semi-purified fraction of rhizomes of Podophyllum hexandrum, in Swiss albino Strain 'A' mice exposed to 10 Gy whole-body gamma radiation. Animals were treated with 10 and 15 mg/kg b wt (i.p.) of REC-2001 1h prior to exposure to a lethal dose of gamma-radiation (10 Gy) and observed upto 30 days. For analysis of maximum tolerable dose (MTD), LD(50) and acute toxic dose, different concentrations of the extract were administered to animals and their mortality and morbidity status was observed upto 72 h and one week, respectively. Dose reduction factor (DRF) was determined by exposing REC-2001 pre-treated mice to supra-lethal doses of gamma-radiation. Endogenous spleen colony forming units (CFU), DNA strand breaks in thymocytes (alkaline halo assay) and lipid degradation was studied to understand the mechanism of radioprotection. A single dose of REC-2001 (10 and 15 mg/kg b wt i.p.) exhibited >90% survival in the pre-treated irradiated group versus no survival in radiation control group. Single doses of upto 75 mg/kg b wt (i.p.) did not cause any mortality (MTD) in mice. REC-2001, a dose of 90 mg/kg b wt, resulted in 50% mortality (LD(50)), while the LD(100) was 115 mg/kg b wt REC-2001 exhibited a DRF of 1.62. CFU counts in the REC-2001 treated group were found significantly high (5.33/spleen) as compared to controls. Exposure of thymocytes to 10 Gy radiation resulted in increased halo diameter (45+/-3 microm) in comparison to untreated controls (8+/-1 microm). REC-2001 administration (500 microg/ml) decreased the halo diameter to 15+/-2 microm. Radiation-induced lipid degradation was also inhibited by REC-2001. The present study has revealed that REC-2001 is a promising radioprotective fraction that can be effectively used against lethal doses of gamma-radiation after further investigations in higher animal models.
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Abstract
BF3OEt2-catalysed glycosidation of phenolic compounds 3 and 6 with the mannofuranosyl glycosyl donor 2 separately gave the corresponding alpha-mannofuranosyl derivatives 4 and 7 in good yield, and the latter on selective deacetonation (hydrolysis) with 2% aqueous HCl afforded 5 and 8 respectively. Compounds 4 and 7 inhibited rat intestinal alpha-glucosidase more effectively than a standard drug acarbose.
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Can we differentiate true white matter fibers from pseudofibers inside a brain abscess cavity using geometrical diffusion tensor imaging metrics? NMR IN BIOMEDICINE 2008; 21:581-588. [PMID: 18050359 DOI: 10.1002/nbm.1228] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
High fractional anisotropy (FA) usually reflects the orientation and integrity of white matter (WM) fibers. Other regions of increased FA have been described, such as brain abscesses, developing cortex, and areas of hemorrhage. It may not be possible to differentiate true fibers from the pseudofibers found inside an abscess cavity on the basis of FA and mean diffusivity (MD). The aim of this study was to differentiate true WM fibers from pseudo WM tracts inside the abscess cavity using geometrical diffusion tensor imaging metrics [linear anisotropy (CL), planar anisotropy (CP), and spherical anisotropy (CS)]. Diffusion tensor imaging was performed in 42 patients with brain abscess and 10 age/sex-matched controls. Automated segmentation using Java-based software divided the abscess cavity into two sub-regions with FA < 0.20 and FA > or = 0.20. Quantitation was carried out on the sub-regions of the abscess cavity with FA > or = 0.20. In healthy controls, regions of interest were placed on the corpus callosum, posterior limb of the internal capsule, and periventricular and subcortical WM. Significantly increased CP values were observed inside the abscess cavity compared with various normal WM regions. Significantly increased FA and CL values were observed in the abscess cavity compared with subcortical WM only. However decreased FA and CL values were observed in the cavity compared with the corpus callosum, posterior limb of the internal capsule, and periventricular WM. The 95% confidence intervals of means for the abscess cavity were well separated from those for WM in the case of CL and CP; however, they overlapped in the case of FA, MD, and CS. High CP with low CL inside the abscess cavity suggests that the shape of the diffusion tensor is predominantly planar, whereas it is linear in WM tracts. These geometrical indices may have advantages over FA for differentiating true from pseudo WM tracts inside the abscess cavity.
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Assessment of the metabolic profile in Type 2 diabetes mellitus and hypothyroidism through proton MR spectroscopy. Magn Reson Imaging 2008; 26:420-5. [PMID: 18164573 DOI: 10.1016/j.mri.2007.08.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2007] [Revised: 08/08/2007] [Accepted: 08/08/2007] [Indexed: 11/16/2022]
Abstract
The metabolic changes in the brain of patients affected with Type 2 diabetes mellitus (DM) alone, both Type 2 DM and hypothyroidism and hypothyroidism only were investigated using proton magnetic resonance spectroscopy ((1)H MRS). Single-voxel spectroscopy was carried out in right and left frontal lobe white matter, left parietal white matter and left occipital gray matter. Choline (Cho)/creatine (Cr) value was found to be increased in the left occipital gray matter of the subjects affected with Type 2 DM and both Type 2 DM and hypothyroidism as compared to controls. No significant change in the Cho/Cr value in the occipital gray matter was observed in hypothyroid subjects as compared to controls. However, they showed an increased level of Cho/Cr in the frontal white matter. High Cho is associated with altered membrane phospholipid metabolism. The high Cho in frontal white matter in hypothyroids and occipital gray matter in diabetic patients suggests that, though both the diseases are endocrine disorders, they differ from each other in terms of regional brain metabolite changes.
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Etiological profile of stroke and its relation with prothrombotic states. Indian J Pediatr 2008; 75:579-84. [PMID: 18759085 DOI: 10.1007/s12098-008-0112-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2007] [Accepted: 03/17/2008] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To study the etiological profile of childhood stroke and its relation with prothrombotic states. METHODS Children with acute stroke with no evidence of CNS infection or head injury were studied. Stroke was confirmed by CT scan and further evaluated by MRI. Cardiac status was assessed with transthoracic echocardiography. Test for hypercoagulable state (antithrombin III, protein C, protein S, anticardiolipin antibody IgG and IgM and lupus anticoagulant) were done in all patients. RESULTS A total of 66 children were enrolled--36 cases and 30 controls. Presenting symptoms were motor deficit (72%), seizure (66%), altered sensorium (36%), aphasia (27%). Causes identified were antiphospholipid antibody syndrome (25%), Moya Moya disease (16.6%), cardiac disease (11.1%), vasculitis (5.5%), ATIII deficiency (5.5%), Protein C deficiency (2.7%). Etiology remained unknown in 25% of cases with infarction. Hemorrhage was seen in 8.2% of cases and they had DIC or liver disease as the underlying cause. CONCLUSIONS Magnetic Resonance Angiography and ELISA for antiphospholipid antibody should be done in all patients with stroke without an obvious cause.
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Abstract
Mesenchymal stem cells (MSCs) represent an adherent, fibroblast-like population present not only in the bone marrow, but in a number of tissues, including blood, adipose tissue, muscle, and dermis. Their extensive proliferation and transdifferentiation potential makes them best suited for tissue engineering applications. Identification of growth factors and signaling pathways involved in self-renewal and differentiation is important for designing strategies to overcome replicative senescence and attain directed differentiation. Wnt, bone morphogenetic protein (BMP), and Notch pathways have been implicated to play key roles in self-renewal and differentiation of hematopoietic, intestinal, and epidermal stem cells. They are also involved in regulating MSC differentiation. However, MSC self-renewal has not received much attention, with Nucleostemin being the only recently identified proliferation molecule. Although immortalization using viral oncogenes and telomerase has been achieved, transformation in long-term cultures is a potential risk. Understanding of the mechanisms governing osteogenic differentiation of MSCs is expanding with the recent identification of two major transcription factors, Osterix and Runx2. Enhanced expansion as well as osteogenic differentiation of MSCs can be attained using a combinatorial approach involving co-expression of proliferation and differentiation genes. However, a thorough understanding of the molecular mechanism is necessary for enhancing the self-renewal ability and osteogenic potential in vitro.
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Abstract
Tc-99m MDP and Tc-99m ciprofloxacin scans were performed in 14 patients with suspected tubercular bone disease and in 2 cases of nontubercular bone infection. In 5 patients the findings were true negative. There were no false positives and 1 was false negative. The sensitivity, specificity, and positive predictive value were found to be 93, 71, and 87.5%, respectively, for detection of bone tubercular lesions. However, the test does not distinguish TB osteomyelitis from other types of osteomyelitis. Delayed 24 hour scans were found useful to differentiate between inflammatory and infective lesions. The aim of this study was to evaluate the usefulness of the Tc-99m ciprofloxacin scan as a means to detect tubercular bone disease.
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Protective efficacy of semi purified fraction of high altitude podophyllum hexandrum rhizomes in lethally irradiated Swiss albino mice. Cell Mol Biol (Noisy-le-grand) 2007; 53:29-41. [PMID: 17543231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2006] [Accepted: 01/04/2007] [Indexed: 05/15/2023]
Abstract
A fraction of high altitude Podophyllum hexandrum rhizome, REC-2006, was evaluated for its radioprotective efficacy against lethal gamma-irradiation (10 Gy, whole body) in Swiss albino mice. The maximum tolerated dose (MTD) and LD50 of this fraction were found to be 45 mg/kg b.w. and 74 mg/kg b.w. respectively. Pre-irradiation (- 2 h, ) administration (i.p.) of 6 or 8 mg/kg b.w. of REC-2006 rendered > 90% survival in lethally irradiated mice. The dose reduction factor was calculated to be 1.62 considering survival as the end point. REC-2006 treatment marked in significant increase in endogenous spleen colony forming units. In REC-2006 treated group, super oxide dismutase activity was increased significantly compared to the radiation control group (Liver, p = 0.00, Jejunum p = 0.00). The extract also inhibited radiation induced lipid peroxidation in liver (p = 0.00) at 24 h. REC-2006 administration (100-200 microg/ml) significantly reduced the halo diameter in mice thymocytes. Nearly 10 fold difference between the effective dose (6 mg/kg b.w.) and LD50 and the high degree of whole body survival (> 90% against 10 Gy irradiation) indicates REC-2006 to be safe and highly promising to achieve significant radioprotection against lethal radiation. Further purification and identification of active molecules and their efficacy studies in higher animals therefore demand attention.
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Cytoprotective effect of Podophyllum hexandrum against gamma radiation is mediated via hemopoietic system stimulation and up-regulation of heme-oxygenase-1 and the prosurvival multidomain protein Bcl-2. Integr Cancer Ther 2007; 6:54-65. [PMID: 17351027 DOI: 10.1177/1534735406298303] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The radioprotective effect of a hydroalcoholic extracted material (REC-2000) from the rhizome of Podophyllum hexandrum was studied in mice exposed to lethal gamma radiation (10 Gy). The extract (REC-2000) was found to restore the hemoglobin content (14.73 +/- 0.33) and total leukocyte count (TLC) (4166.66 +/- 0.02) in lethally (10 Gy) gamma-irradiated mice on the 15th day in comparison to the radiation control mice. The hemoglobin content of the drug + radiation group was observed to be significantly (21.25%) higher than the radiation control group on the 10th day. Similarly, the TLC was significantly increased (83.33 times) in the drug + radiation group as compared to a radiation (10 Gy) only group on the 10th day. Enhanced expression of heme-oxygenase-1 and Bcl-2 protein observed by Western blotting further supports the observation of hemopoietic recovery in irradiated mice. These findings indicate that the bioactive constituents present in REC-2000 exert the radioprotective effect by modulating the hemopoietic system.
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Stem cell c-KIT and HOXB4 genes: critical roles and mechanisms in self-renewal, proliferation, and differentiation. Stem Cells Dev 2007; 15:755-78. [PMID: 17253940 DOI: 10.1089/scd.2006.15.755] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Hematopoietic stem cells (HSCs) possess a distinct ability to perpetuate through self-renewal and to generate progeny that differentiate into mature cells of myeloid and lymphoid lineages. A better understanding of the molecular mechanisms by which HSCs replicate and differentiate from the perspective of developing new approaches for HSC transplantation is necessary for further advances. The interaction of the receptor tyrosine kinase--c-KIT--with its ligand stem cell factor plays a key role in HSC survival, mitogenesis, proliferation, differentiation, adhesion, homing, migration, and functional activation. Evidence that activating site-directed point mutations in the c-KIT gene contributes to its ligand-independent constitutive activation, which induces enhanced proliferation of HSCs, is accumulating. Similarly, and equally important, self-renewal is a process by which HSCs generate daughter cells via division. Self-renewal is necessary for retaining the HSC pool. Therefore, elucidating the molecular machinery that governs self-renewal is of key importance. The transcription factor, HOXB4 is a key molecule that has been reported to induce the in vitro expansion of HSCs via self-renewal. However, critical downstream effector molecules of HOXB4 remain to be determined. This concisely reviewed information on c-KIT and HOXB4 helps us to update our understanding of their function and mechanism of action in self-renewal, proliferation, and differentiation of HSCs, particularly modulation by c-KIT mutant interactions, and HOXB4 overexpression showing certain therapeutic implications.
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Diastereoselective synthesis of glycosylated prolines as α-glucosidase inhibitors and organocatalyst in asymmetric aldol reaction. Bioorg Med Chem Lett 2007; 17:1321-5. [PMID: 17188491 DOI: 10.1016/j.bmcl.2006.12.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Revised: 11/22/2006] [Accepted: 12/01/2006] [Indexed: 11/23/2022]
Abstract
1,3-Dipolar cycloaddition of azomethine ylides and glycosyl E-olefins in presence of LDA led to diastereoselective formation of C-glycosylated proline esters. The selected esters on regioselective hydrolysis with LiOH gave C-glycosyl prolines. Few of the proline esters exhibited very good alpha-glucosidase inhibitory activity. The organocatalytic activity of the proline derivatives in a prototype Aldol reaction has also been investigated.
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Synthesis and antitubercular activity of substituted phenylmethyl- and pyridylmethyl amines. Bioorg Med Chem 2006; 14:8186-96. [PMID: 17010617 DOI: 10.1016/j.bmc.2006.09.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2006] [Revised: 09/09/2006] [Accepted: 09/12/2006] [Indexed: 11/29/2022]
Abstract
A total of 42 benzyl- and pyridylmethyl amines were synthesized either by reductive amination of aromatic/heteroaromatic aldehydes with amines or by conjugate addition of amines to the cinnamates followed by reduction of the ester group with lithium aluminium hydride to the respective propanolamines. All the synthesized compounds were evaluated against both avirulent and virulent strains of Mycobacterium tuberculosis. Many of the compounds exhibited MIC as low as 1.56microg/mL. Few of potent compounds were also evaluated against clinical isolates of MDR TB and found to be active at one or other concentrations with MIC as low as 3.12microg/mL.
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Cortical activation during finger tapping in thyroid dysfunction: A functional magnetic resonance imaging study. J Biosci 2006; 31:543-50. [PMID: 17301491 DOI: 10.1007/bf02708405] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Thyroid dysfunction is associated with attention deficit and impairment of the motor system (muscle weakness and fatigue). This paper investigates possible motor function deficit in thyroid patients,compared to the controls. Functional MRI studies (fMRI)were carried out in five hypo and five hyperthyroid patients and six healthy volunteers. Whole brain imaging was performed using echo planar imaging (EPI)technique, on a 1.5T whole body MR system (Siemens Magnetom Vision). The task paradigm consisted of 8 cycles of active and reference phases of 6 measurements each, with right index finger tapping at a rate of 120 taps/min. Post-processing was performed using statistical parametric mapping on a voxel-by-voxel basis using SPM99. Clusters of activation were found in the contralateral hemisphere in primary somatomotor area (M1), supplementary motor area (SMA), somatosensory,auditory receptive and integration areas, inferior temporal lobe, thalamus and cerebellum. Increased clusters of activation were observed in M1 in thyroid subjects as compared to controls and with bilateral activation of the primary motor cortex in two hyperthyroid patients. The results are explained in terms of increased functional demands in thyroid patients compared to volunteers for the execution of the same task.
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Search of antitubercular activities in tetrahydroacridines: Synthesis and biological evaluation. Bioorg Med Chem Lett 2006; 16:5144-7. [PMID: 16870429 DOI: 10.1016/j.bmcl.2006.07.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2006] [Revised: 07/04/2006] [Accepted: 07/07/2006] [Indexed: 11/21/2022]
Abstract
A series of 9-substituted tetrahydroacridines were synthesized by nucleophilic substitution of chloro group with different nucleophiles in 9-chlorotetrahydroacridine (2). The latter could be obtained by POCl(3) mediated cyclization of the intermediate enamine, which in turn, was prepared by acid catalyzed condensation of anthranilic acid and cyclohexanone. Most of the compounds on antitubercular evaluation against M. tuberculosis H37 Rv and H37 Ra strains exhibited potent activities with MIC 6.125-0.78 microg/mL comparable to the standard drugs.
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Zingiber officinale exhibits behavioral radioprotection against radiation-induced CTA in a gender-specific manner. Pharmacol Biochem Behav 2006; 84:179-88. [PMID: 16797061 DOI: 10.1016/j.pbb.2006.04.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Revised: 03/30/2006] [Accepted: 04/18/2006] [Indexed: 11/23/2022]
Abstract
At the organismic level, exposure to radiation can produce taste aversion (CTA) learning and emesis, which have been proposed as behavioral endpoints that are mediated by harmful effects of radiations on peripheral systems, primarily the gastrointestinal system. Thus, the aim of the present investigation was to study the gastroprotective action of hydroalcoholic extract of zingiber rhizome (Zingiber officinale Rosc.) against radiation-induced conditioned taste aversion (CTA) in both male and female species of animals, for testing its potential as a behavioral radioprotector. Administration of zingiber extract 1 h before 2-Gy gamma-radiation was significantly effective in blocking the saccharin avoidance response, with 200 and 250 mg/kg b.wt. i.p., being the most effective doses for male and female rats, respectively. A comparison of the efficacy of zingiber extract with two antiemetic drugs, ondansteron and dexamethasone, revealed that the extract rendered comparable protection against radiation-induced CTA. Our experiments also confirmed the existence of sex dichotomy (i.e., the sex of animal greatly influenced response towards radiation exposure) in relation to behavioral responses (CTA) or differential metabolism. The observed gender variations were hypothesized to be a result of hormonal fluctuations and differences in pharmacological parameters in male and female rats. To correlate the mechanism of action, the free-radical-scavenging potential of zingiber extract to scavenge hydroxyl ion and nitric oxide was also tested, in cell-free system and a concentration of 1000 microg/ml, was found to be the most potent, which has been proposed as one the many activities assisting in its overall ability to modulate radiation-induced taste aversion. The results demonstrate that Z. officinale possesses antioxidant, radioprotective and neuromodulatory properties that can be effectively utilized for behavioral radioprotection and for efficiently mitigating radiation-induced CTA in both males and females species.
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Abstract
Malaria caused by Plasmodium parasites kills approximately 1-3 million people and causes disease in 300-500 million people annually throughout the world. The current approaches to curtail this disease include vector control, vaccination, immunotherapy and chemotherapy. The vector control is achieved by reducing vector density, interrupting their life cycle, and creating a barrier between the human host and mosquitoes. A number of vaccine candidates are being clinically tried and R&D effort in this direction is coming in a big way. Currently there are only limited safe drugs for the treatment of this disease, however, reports of emerging resistance against existing drugs warrant the introduction of new drugs, which are unlikely to come from pharmaceutical industries because of limited commercial opportunities. One of the most important current approaches to develop new drugs involves the synthesis of chemical libraries and evaluate them against most validated biochemical targets of malarial parasite. Although a number of such targets in antimalarial drug development are known today, yet only validated and selective biochemical targets including mitochondrial transport, glycolic pathway, folate pathway, proteases and heme metabolism, apicoplast metabolism, glycophospatidyl inositol, lipid metabolism (glycerophospholipids), peptidyl deformylase and oxidative stress in parasite-infected erythrocytes have been discussed here. The well known antimalarial drugs and different drug combinations for the treatment of malaria are also briefly reviewed. A survey of the recently discovered new molecules active against malaria has also been narrated. Lastly, the future of malaria chemotherapy and new directions emerging from literature has been elucidated.
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Optimizing cancer radiotherapy with 2-deoxy-d-glucose dose escalation studies in patients with glioblastoma multiforme. Strahlenther Onkol 2005; 181:507-14. [PMID: 16044218 DOI: 10.1007/s00066-005-1320-z] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2004] [Revised: 05/13/2005] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND PURPOSE Higher rates of glucose utilization and glycolysis generally correlate with poor prognosis in several types of malignant tumors. Own earlier studies on model systems demonstrated that the nonmetabolizable glucose analog 2-deoxy-D-glucose (2-DG) could enhance the efficacy of radiotherapy in a dose-dependent manner by selectively sensitizing cancer cells while protecting normal cells. Phase I/II clinical trials indicated that the combination of 2-DG, at an oral dose of 200 mg/kg body weight (BW), with large fractions of gamma-radiation was well tolerated in cerebral glioma patients. Since higher 2-DG doses are expected to improve the therapeutic gain, present studies were undertaken to examine the tolerance and safety of escalating 2-DG dose during combined treatment (2-DG + radiotherapy) in glioblastoma multiforme patients. PATIENTS AND METHODS Untreated patients with histologically proven glioblastoma multiforme (WHO criteria) were included in the study. Seven weekly fractions of (60)Co gamma-rays (5 Gy/fraction) were delivered to the tumor volume (presurgical CT/MRI evaluation) plus 3 cm margin. Escalating 2-DG doses (200-250-300 mg/kg BW) were administered orally 30 min before irradiation after overnight fasting. Acute toxicity and tolerance were studied by monitoring the vital parameters and side effects. Late radiation damage and treatment responses were studied radiologically and clinically in surviving patients. RESULTS Transient side effects similar to hypoglycemia were observed in most of the patients. Tolerance and patient compliance to the combined treatment were very good up to a 2-DG dose of 250 mg/kg BW. However, at the higher dose of 300 mg/kg BW, two out of six patients were very restless and could not complete treatment, though significant changes in the vital parameters were not observed even at this dose. No significant damage to the normal brain tissue was observed during follow-up in seven out of ten patients who received complete treatment and survived between 11 and 46 months after treatment. CONCLUSION Oral administration of 2-DG combined with large fractions of radiation (5 Gy/fraction/week) is safe and could be tolerated in glioblastoma patients without any acute toxicity and late radiation damage to the normal brain. Further clinical studies to evaluate the efficacy of the combined treatment are warranted.
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Synthesis and antitubercular activities of bis-glycosylated diamino alcohols. Bioorg Med Chem 2005; 13:5668-79. [PMID: 15955703 DOI: 10.1016/j.bmc.2005.05.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2005] [Revised: 05/13/2005] [Accepted: 05/13/2005] [Indexed: 11/26/2022]
Abstract
Conjugate addition of diamines to glycosyl olefinic esters 1a and 1b followed by reduction of resulting bis-glycosyl beta-amino esters (2-7 and 14-19) with lithium aluminium hydride led to the respective glycosyl amino alcohols (8-13 and 20-25) in moderate to good yields. All the compounds were evaluated for antitubercular activity against Mycobacterium tuberculosis H(37)Ra and H(37)Rv. Few of the compounds exhibited antitubercular activity with MIC as low as 6.25-3.12microg/mL in virulent and avirulent strains. Compound 13 was found to be active against MDR strain and showed mild protection in mice.
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An efficient synthesis of aryloxyphenyl cyclopropyl methanones: a new class of anti-mycobacterial agents. Bioorg Med Chem Lett 2005; 15:4526-30. [PMID: 16087335 DOI: 10.1016/j.bmcl.2005.07.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2005] [Revised: 06/28/2005] [Accepted: 07/04/2005] [Indexed: 10/25/2022]
Abstract
An efficient, high yield and one-pot synthesis of phenyl cyclopropyl methanones by reaction of different aryl alcohols with 4'-fluoro-4-chloro-butyrophenone in THF/DMF in the presence of NaH/TBAB is reported. Most of the methanones were further reduced to respective alcohols or methylenes. All the compounds were evaluated for their anti-tubercular activities against M. tuberculosis H37Rv in vitro displaying MICs ranging from 25 to 3.125 microg/mL. The most active compounds showed activity against MDR strains and two of them (14 and 16) showed marginal enhancement of MST in mice.
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