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Terms modified by Kb Selected AbstractsMulticenter clinical experience with flow cytometric method for fetomaternal hemorrhage detectionCYTOMETRY, Issue 6 2002Jenn C. Chen Abstract BACKGROUND Enumeration of fetal red blood cells (RBCs) is important in the management of fetomaternal hemorrhage (FMH), particularly in situations of Rh incompatibility. METHODS We evaluated results from three institutions using the flow cytometric method (FCM) to detect fetal RBCs based on the anti-hemoglobin F (HbF) monoclonal antibody method. RESULTS During 1997,2001, 69 of 1,248 patients (5.5%) had measurable fetal erythrocytes (RBCs) in maternal blood. Only 21 patients (1.7%) had more than 30 mL of fetal blood detected in maternal blood. Of the 11 patients with large FMH and clinical follow-up, 7 had fetal demise (64%). In positive samples, significant differences were found in the fluorescence intensity (FI) of anti-HbF antibody staining between HbF-negative erythrocytes (HbF-) and adult HbF containing erythrocytes (F cells; 4 ± 0 versus 57 ± 9 linear mean channels [LMC]; P < 0.001) and between HbF-cells and fetal RBCs (4 ± 0 versus 433 ± 136 LMC; P < 0.001). In addition, significant differences were observed in forward light scatter intensity between HbF-cells and fetal RBCs (298 ± 15 versus 355 ± 68 LMC, P = 0.03). The transportability of the test is also addressed by comparing results from two other laboratories. The experience of our three laboratories, as well as the results from the recently reinitiated College of American Pathologists survey, which compares FCM and manual methods, clearly documents the superiority of the FCM test over the manual Kleihauer-Betke (KB) test. CONCLUSIONS The FCM is a simpler, more objective, and more precise alternative to the KB method in clinical testing. The high mortality rate associated with large FMH and therapeutic implications of these results should give laboratories motivation to abandon the KB method with more robust FCM to detect FMH. Cytometry (Clin. Cytometry) 50:285,290, 2002. © 2002 Wiley-Liss, Inc. [source] Inorganic Drug-Delivery Nanovehicle Conjugated with Cancer-Cell-Specific LigandADVANCED FUNCTIONAL MATERIALS, Issue 10 2009Jae-Min Oh Abstract The surface of layered double hydroxide nanoparticles, a potential drug-delivery nanovehicle, is modified with the cancer-cell-specific ligand, folic acid. The surface modification is successfully accomplished through step-by-step coupling reactions with aminopropyltriethoxysilane and 1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide. In order to evaluate the cancer-cell targeting effect of folic-acid-grafted layered double hydroxide utilizing fluorescence-related assay, both layered double hydroxide with and without folic acid moiety are labeled with fluorescein 5,-isothiocyanate. The uptake of layered double hydroxide and folic acid conjugated into KB and A549 cells is visualized using fluorescence microscopy and measured by flow cytometry. Both chemical and biological assay results demonstrate that the folic acid molecules are indeed conjugated to the surface of layered double hydroxide and thus the selectivity of nanovehicles to cancer cells overexpressing folate receptors increases. In this study, it is suggested that layered double hydroxide nanoparticles can be used as drug-delivery carriers with a targeting function due to the chemical conjugation with specific ligand. [source] Differentially expressed genes associated with CIS -diamminedichloroplatinum (II) resistance in head and neck cancer using differential display and CDNA microarrayHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 3 2003Eisaku Higuchi MD Abstract Background. The mechanism by which cancer cells become resistant to cis -Diamminedichloroplatinum (II) (cDDP) is not completely understood. To investigate the molecular markers involved in the cDDP resistance, we compared the gene expression profiles between a head and neck squamous cell carcinoma (HNSCC) line sensitive to cDDP and its cDDP-resistant variant. Methods. Both a fluorescent differential display and a cDNA microarray analysis were applied to distinguish the gene profiles between KB, a human HNSCC line, and its cDDP-resistant variant (KB/cDDP). These results were confirmed by Northern blot analysis. Results. One up-regulated gene, glycoprotein hormone ,-subunit, and two down-regulated genes coding membrane proteins, human folate receptor and tumor-associated antigen L6, were identified in KB/cDDP cells. Conclusions. Our findings suggest that development of the cDDP-resistant phenotype is accompanied by alternations of gene expression including a glycoprotein hormone and membrane proteins. These gene products could be new molecular markers for resistance to cDDP. © 2003 Wiley Periodicals, Inc. Head Neck 25: 187,193, 2003 [source] Pyrrolizidine Alkaloids and Bisabolane Sesquiterpenes from the Roots of Ligularia cymbuliferaHELVETICA CHIMICA ACTA, Issue 2 2008Chun-Mei Liu Abstract The new pyrrolizidine alkaloid glycoside 1, and the three new highly oxygenated bisabolane sesquiterpenes 4,6, together with the two known pyrrolizidine alkaloids 2 and 3, were isolated from the roots of Ligularia cymbulifera (W.,W. Smith) Hand.- Mazz. Their structures were established on the basis of spectroscopic analysis, especially 1D- and 2D-NMR data. The cytotoxic activities of compounds 1, 2, and 4,6 were evaluated against hepatoma (BEL-7402), human leukemia (HL-60), human ovarian carcinoma (HO-8910), and nasopharyngeal carcinoma (KB) cell lines (Tables 1,3). Compound 6 showed weak cell-growth inhibition of BEL-7402 cell. [source] Spectral, kinetic, and redox properties of basic fuchsin in homogeneous aqueous and sodium dodecyl sulfate micellar mediaINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 12 2003N. Ramanathan Effect of anionic surfactant on the optical absorption spectra and redox reaction of basic fuchsin, a cationic dye, has been studied. Increase in the absorbance of the dye band at 546 nm with sodium dodecyl sulfate (SDS) is assigned to the incorporation of the dye in the surfactant micelles with critical micellar concentration (CMC) of 7.3 × 10,3 mol dm,3. At low surfactant concentration (<5 × 10,3 mol dm,3) decrease in the absorbance of the dye band at 546 nm is attributed to the formation of a dye,surfactant complex (1:1). The environment, in terms of dielectric constant, experienced by basic fuchsin inside the surfactant micelles has been estimated. The association constant (KA) for the formation of dye,SDS complex and the binding constant (KB) for the micellization of dye are determined. Stopped-flow studies, in the premicellar region, indicated simultaneous depletion of dye absorption and formation of new band at 490 nm with a distinct isosbestic point at 520 nm and the rate constant for this region increased with increasing SDS concentration. The reaction of hydrated electron with the dye and the decay of the semireduced dye are observed to be slowed down in the presence of SDS. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 35: 629,636, 2003 [source] Evaluation of F cells in sickle cell disorders by flow cytometry , comparison with the Kleihauer,Betke's slide methodINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 6 2007K. Y. ITALIA Summary Adult F cell numbers are raised in inherited haemoglobin disorders, such as , -thalassaemia and sickle cell anaemia, hereditary persistence of foetal haemoglobin, and some acquired conditions, such as juvenile myelomonocytic leukaemia, during acute erythropoietic stress and pregnancy. True foetal erythrocytes containing foetal amounts of HbF can also occur in the adult circulation during the leakage of HbF-containing cells from the foetus to the maternal circulation. In normal adults, HbF is restricted to a small proportion (3,7%) of red blood cells (RBC), termed ,F cells'. Techniques estimating the amount of HbF use lysates prepared from RBC, whereas those that estimate the adult F cell count use intact RBC. An accurate assessment of adult F cells in sickle cell disorders is important because increased adult F cells are associated with decreased morbidity in these disorders. In the present study, HbF levels were measured and adult F cell numbers were estimated in 100 blood samples (25 normal individuals, 25 sickle heterozygotes, 25 sickle homozygotes and 25 sickle , -thalassaemia cases), using high pressure liquid chromatography for HbF levels, and flow cytometry and the Kleihauer,Betke (KB) acid elution microscope slide method for cell counts. Flow cytometry gave a more accurate assessment of adult F cells, eliminating any manual error, as compared to KB, which was less sensitive and precise as it is based on subjective visual interpretation. [source] The totally miscible in ternary hydrogen-bonded polymer blend of poly(vinyl phenol)/phenoxy/phenolicJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2009Shiao-Wei KuoArticle first published online: 28 MAY 200 Abstract The individual binary polymer blends of phenolic/phenoxy, phenolic/poly(vinyl phenol) (PVPh), and phenoxy/PVPh have specific interaction through intermolecular hydrogen bonding of hydroxyl,hydroxyl group to form homogeneous miscible phase. In addition, the miscibility and hydrogen bonding behaviors of ternary hydrogen bond blends of phenolic/phenoxy/PVPh were investigated by using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy, and optical microscopy. According to the DSC analysis, every composition of the ternary blend shows single glass transition temperature (Tg), indicating that this ternary hydrogen-bonded blend is totally miscible. The interassociation equilibrium constant between each binary blend was calculated from the appropriate model compounds. The interassociation equilibrium constant (KA) of each individually binary blend is higher than any self-association equilibrium constant (KB), resulting in the hydroxyl group tending to form interassociation hydrogen bond. Photographs of optical microscopy show this ternary blend possess lower critical solution temperature (LCST) phase diagram. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] Evaluation of Konjac Blends and Soy Protein Isolate as Fat Replacements in Low-fat BolognaJOURNAL OF FOOD SCIENCE, Issue 5 2000K.B. Chin ABSTRACT Low-fat bolognas (LFB, < 2.0% fat) were developed with 2 levels (0.5% or 1.0%) of konjac blends (KB, KSS = konjac flour/starch and KNC = konjac flour/carrageenan/starch) and the replacement of meat proteins with 2% soy protein isolate (SPI, DWB). Increased levels of KB decreased (P < 0.05) lightness and yellowness, and most texture profile analysis (TPA) values. LFB containing 1.0% KB with 2% SPI addition had TPA values and sensory flavor/taste attributes similar to the control (CTL II, 30% fat), whereas LFB formulated with KSS had textural characteristics more similar to CTL II than those with KNC, based on sensory evaluation. [source] Elucidation and decisional risk in a multi-criteria decision based on a Choquet integral aggregation,a cybernetic frameworkJOURNAL OF MULTI CRITERIA DECISION ANALYSIS, Issue 5-6 2005J. Montmain Abstract The authors are developing multi-criteria Decision-making support systems (DMSS) for project teams in charge of selecting a technical solution among alternatives. They propose a cybernetic framework to emphasize the link between decision-making (DM) and knowledge management processes in such projects. These DMSSs rely on the tracking of the accompanying knowledge production of long-term decisional processes by a collective with many actors. Based on knowledge-production management, this paper explains how to design decisional risk evaluation, monitoring and control aids and traceability functions for strategic choices and logical argumentation. The DMSS is seen as a recommender system for the project manager. Each possible solution involved in the decision-making process (DMP) is evaluated by means of a set of criteria. The evaluation results from an interpretation of the knowledge items in terms of satisfaction scores of the solutions according to the considered criteria. Aggregating these partial scores provides a ranking of all the possible solutions by order of preference. As criteria are sometimes interacting, the aggregation has to be based on adapted operators, i.e. Choquet integrals. Evaluating possible solutions by the knowledge contained in the knowledge base (KB) opens the way to automating the argumentation of the project team's decisions: the argumentation principle underlying this approach is based naturally on coupling a knowledge dynamical management system (KDMS) with the DMSS. The DMSS also evaluates the decisional risk that reflects the eventuality of a wrong selection due to the insufficiency of available knowledge at a given time in order to adopt a reliable solution. Decisional risk assessment corresponds to sensitivity analyses. These analyses are then exploited to control the decisional risk in time: they enable to identify the crucial information points for which additional and deeper investigations would be of great interest to improve the stability of the selection in the future. The knowledge management of a collective project is represented as a control loop: the KDMS is the actuator, the risk accompanying the decision is the controlled variable and is strongly linked to the entropy of the KB managed by the KDMS. Each of the three phases,intelligence, design, choice,of the DMP is identified to a function of the control loop: actuator, process and regulator. This cybernetic framework for decision has its origin in knowledge management activities for a great-scale project,the EtLD project of the French Atomic Commission (CEA) that concerns the management of high-level long-life radioactive waste in France. Copyright © 2007 John Wiley & Sons, Ltd. [source] Parameters of drug antagonism: re-examination of two modes of functional competitive drug antagonism on intraocular musclesJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 8 2004Popat N. Patil There are two distinct kinetic functional pharmacological procedures by which the equilibrium affinity constant, KB, of a competitive reversible blocker is obtained. The classical method on an organ system requires the study of the parallel displacement of the agonist concentration-response curve in the presence of the blocker. In the second method, the agonist-evoked functional mechanical response is reduced to half by the blocker IC50 (the concentration required for 50% inhibition). In relation to these parameters the role of the ionization constant pKa and liposolubility log Pc or log D of blockers was examined. On the ciliary muscle from human eye, IC50/KB ratios for (±)-atropine, its quaternary analogue (±)-methylatropine, (-)-scopolamine, (±)-cyclopentolate, (-)-tropicamide, (±)-oxybutynin and pirenzepine were 15, 23, 4.4, 2.6, 1.66, 1.46 and 1.71, respectively. The ratios on the iris sphincter were comparable with those of ciliary muscle. When compared with large proportions of ionized molecules with water soluble properties of (±)-atropine and (±)-methylatropine, relatively high amounts of un-ionized and/or with greater partitioning of all other blockers in the lipoid barrier co-related well to low IC50/KB ratios, as predicted by the classical theory of competitive drug antagonism. It was hypothesized that due to receptor biophase access, the reduction of the mechanical response of the agonist by the highly ionized water-soluble antagonist at IC50 represented time-distorted "pseudo-equilibrium" estimation, where a higher concentration of the blocker was needed. On the other cholinergic effectors, like that of rat anococcygeus muscle or frog rectus abdominus muscle, IC50/KB ratios of respective blockers atropine or (+)-tubocurarine and hexamethonium were close to 1. Thus physicochemical properties, which affect the distribution coefficient log D and the tissue morphology (where asymmetric distribution of receptors may occur), appeared to be a critical factor in the analysis of the affinity parameters of the competitive reversible blocker. On the intraocular muscles, two functional pharmacological procedures for obtaining KB and IC50 values were not kinetically equivalent. [source] Structure elucidation of two new xanthone derivatives from the marine fungus Penicillium sp. (ZZF 32#) from the South China SeaMAGNETIC RESONANCE IN CHEMISTRY, Issue 11 2008Changlun Shao Abstract Two new xanthones, 8-(methoxycarbonyl)-1-hydroxy-9-oxo-9H-xanthene-3-carboxylic acid (1) and dimethyl 8-methoxy-9-oxo-9H-xanthene-1, 6-dicarboxylate (2) and one known xanthone methyl 8-hydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylate (3) were isolated from the culture broth of the mangrove fungus Penicillium sp. (ZZF 32#) collected from the South China Sea. Their structures were established by comprehensive analysis of one-dimensional (1D) and two-dimensional (2D) NMR data. The structure of compound 3 was confirmed by X-ray crystallography, which led to the suggestion that janthinone (4) might have the same structure as 3. Compounds 1,3 were inactive against KB or KBv200 cells during cytotoxicity evaluations. Copyright © 2008 John Wiley & Sons, Ltd. [source] Glial cytoplasmic inclusions and tissue injury in multiple system atrophy: A quantitative study in white matter (olivopontocerebellar system) and gray matter (nigrostriatal system)NEUROPATHOLOGY, Issue 3 2008Keisuke Ishizawa Glial cytoplasmic inclusions (GCIs) and microglia were quantified in 12 cases of multiple system atrophy (MSA) with special reference to their association with histologically defined lesion severity. The targets of the analysis were white matter (cerebellum, pontine base) and gray matter (putamen, substantia nigra). First, the lesion severity was defined: for white matter, the degree of demyelination and tissue rarefaction were semi-quantified on Klüver-Barrera (KB) sections as grade I (mildly injured), II (moderately injured), and III (severely injured); for gray matter, neurons and astrocytes were counted on KB and glial fibrillary acidic protein-immunostained sections, respectively. Next, the GCI burden was quantified on sections immunostained for ,-synuclein, phosphorylated ,-synuclein, and ubiquitin and the microglial burden was quantified on sections immunostained for HLA-DR. In white matter, the GCI and microglial burdens were the greatest when the tissue injury was mild and/or moderate (grade I and/or grade II), and they became less prominent when the tissue injury became more severe (grade III). In gray matter, in contrast, the GCI and microglial burdens failed to show significant correlations with the lesion severity. Our result suggests that the amount of GCIs as well as that of microglia is reduced when the tissue injury becomes severe in vulnerable white matter areas, but not in vulnerable gray matter areas, of MSA. It also suggests that there seems to be a difference between gray matter and white matter in the way GCIs and microglia participate in the degenerative process of MSA. [source] Spatiotemporal expression of NGFR during pre-natal human tooth developmentORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 2 2002KB Becktor Structured Abstract Authors, Becktor KB, Hansen BF, Nolting D, Kjær I. Objectives, The relation between nerve growth factor receptor (NGFR) in the human pre-natal tooth buds and the dental follicle was investigated. In particular, we sought to determine if there is a specific pattern of p75NGFR expression in developing human tooth buds and their surrounding tissue. Setting and Sample Population, The Department of Orthodontics at Copenhagen University, Denmark. Histological sections from 11 fetuses, aged 11,21 gestational weeks. Method, The sections were studied by conventional immunohistochemistry. Results, Specific spatiotemporal patterns of p75NGFR reactions were observed in the tooth buds and dental follicle: Before matrix production by the ameloblasts, the entire inner enamel epithelium and the entire dental follicle display p75NGFR immunoreactivity; after matrix production is initiated, the immunoreactivity of the matrix producing cells is lost, as is that of the dental follicle adjacent to these matrix-producing cells. Conclusion, A unique spatiotemporal distribution of NGFR in the pre-eruptive human tooth bud was demonstrated. [source] Effect of Ring Methylation on the Photophysical, Photochemical and Photobiological Properties of cis -Dichlorobis(1,10-Phenanthroline)Rhodium(III)Chloride,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 1 2006Devanesan Loganathan ABSTRACT Methylated analogues of cis -dichlorobis(1,10-phenanthroline)-rhodium(III)chloride (BISPHEN) have been prepared in order to increase the hydrophobicity of the parent compound, and thus create octahedral rhodium (III) complexes suitable for use as anticancer and antiviral agents that can be photo-activated. The parent complex has been shown in earlier work to be unable to cross through cell membranes. Octamethylation, as in the case of cis -dichlorobis(3,4,7,8-tetramethyl-1,10-phenanthroline)rhodium(III)chloride (OCTBP), provides enough hydrophobicity to be taken up by KB tumor cells. It also provides a higher level of ground-state association with double-stranded DNA and increases the quantum efficiency of photoaquation by greater than 10-fold, relative to BISPHEN. OCTBP forms covalent bonds to deoxyguanosine when irradiated with the nucleoside, as has been seen with the parent complex. Irradiation of OCTBP in the presence of the KB or M109 tumor cell lines using narrow-band UVB (,= 311 nm) irradiation initiates a considerable amount of phototoxicity. There is evidence that OCTBP acts as a prodrug (i.e. after passing through the cell membrane the metal complex is photolyzed to cis -chloro aquo OCTBP, which may be the active phototoxic agent). OCTBP and the tetramethyl analogue cis -dichlorobis(4,7-dimethyl-1,10-phenanthroline)rhodium(III)chloride (47TMBP) also show photoaquation upon excitation with visible light (, > 500 nm), and indeed, some phototoxicity of KB cells is observed at these wavelengths as well. This is attributed to direct population of photoactive triplet-excited states. These results, together with our earlier studies of cis -dichloro[dipyrido(3,2-a: 2,,3,-c)phenazine (1,10-phenanthroline)rhodium(III)chloride (DPPZPHEN) demonstrate that such octahedral rhodium complexes are viable "photo-cisplatin" reagents. [source] A steroid fraction of chloroform extract from bee pollen of Brassica campestris induces apoptosis in human prostate cancer PC-3 cellsPHYTOTHERAPY RESEARCH, Issue 11 2007Yao-Dong Wu Abstract Bee pollen of Brassica campestris L. is widely used in China as a natural food supplement and an herbal medicine in strengthening the body's resistance against diseases including cancer. The present study was carried out to investigate the effect of a steroid fraction of chloroform extract from bee pollen of Brassica campestris L. on human cancer cell viability. Our studies show that among nine cancer cell lines of different origin (PC-3, LNCaP, MCF-7, Hela, BEL-7402, BCG-823, KB, A549 and HO8910), this steroid fraction displayed the strongest cytotoxicity in human prostate cancer PC-3 cells. The mode of cell death appeared to be apoptosis in PC-3 cells, as shown by flow-cytometric analysis and fluorescence microscopes. Caspase-3 activity was obviously enhanced after the cells were treated with the fraction. A time-dependent decrease in the expression of anti-apoptotic protein Bcl-2 was also observed by Western blot analysis. It is suggested that the steroid fraction could induce cytotoxicity in prostate cancer PC-3 cells by triggering apoptosis. The studies indicate that the steroid fraction of chloroform extract from bee pollen of Brassica campestris L. may be a promising candidate for the treatment of advanced prostate cancer. Copyright © 2007 John Wiley & Sons, Ltd. [source] Neem leaf preparation induces apoptosis of tumor cells by releasing cytotoxic cytokines from human peripheral blood mononuclear cellsPHYTOTHERAPY RESEARCH, Issue 10 2007Anamika Bose Abstract A neem leaf preparation (NLP) was investigated for its role in the induction of tumor cell apoptosis to elucidate the mechanism of NLP mediated immunoprophylaxis in tumor growth restriction. As NLP did not induce direct apoptosis of human tumor cell lines KB, MCF7 and K562, it was used instead to stimulate human peripheral blood mononuclear cells (PBMC) for 72 h. The PBMC derived culture supernatant (NLP-CS) was observed to induce the restriction of tumor cell proliferation as well as apoptosis. An enzyme linked immunosorbant assay revealed the presence of cytotoxic cytokines, IFN-gamma and TNF-alpha, in the NLP-CS. The inhibition of secretion of IFN-gamma and TNF-alpha in NLP-CS caused a significant decrease in tumor cell apoptosis. Furthermore, stimulation of these tumor cells with NLP-CS resulted in upregulation of the caspase 3 and downregulation of the Bcl 2 and cyclin D1. These observations suggested that NLP could induce tumor cellular apoptosis by releasing cytotoxic cytokines from human PBMC. Copyright © 2007 John Wiley & Sons, Ltd. [source] Evaluation of anticancer activity of the alkaloid fraction of Alstonia scholaris (Sapthaparna) in vitro and in vivoPHYTOTHERAPY RESEARCH, Issue 2 2006Ganesh Chandra Jagetia Abstract The anticancer effect of various doses of an alkaloid fraction of Sapthaparna, Alstonia scholaris (ASERS), was studied in vitro in cultured human neoplastic cell lines (HeLa, HepG2, HL60, KB and MCF-7) and in Ehrlich ascites carcinoma bearing mice. Treatment of HeLa cells with 25 µg/mL ASERS resulted in a time dependent increase in the antineoplastic activity and the greatest activity was observed when the cells were exposed to ASERS for 24 h. However, exposure of cells to ASERS for 4 h resulted in 25% viable cells and hence this time interval was considered to be the optimum time for treatment and further studies were carried out using this time. Treatment of various cells with ASERS resulted in a concentration dependent decline in the viable cells and a nadir was reached at 200 µg/mL in all the cell lines studied. The IC50 was found to be 5.53, 25, 11.16, 10 and 29.76 µg/mL for HeLa, HePG2, HL60, KB and MCF-7 cells, respectively. Similarly, administration of ASERS, once daily for 9 consecutive days to the tumor bearing mice caused a dose dependent remission of the tumor up to 240 mg/kg body weight, where the greatest antitumor effect was observed. Since 240 mg/kg ASERS showed toxic manifestations, the next lower dose of 210 mg/kg was considered as the best effective dose, in which 20% of the animals survived up to 120 days post-tumor-cell inoculation as against no survivors in the saline treated control group. The ASERS treatment resulted in a dose dependent elevation in the median survival time (MST) and the average survival time (AST) up to 240 mg/kg ASERS and declined thereafter. The surviving animals were healthy and disease free. The effect of ASERS was better than cyclophosphamide, which was used as a positive control, where all the animals succumbed to death by 40 days and the MST and AST were 19.5 and 18.3 days, respectively. The effective dose of 210 mg of ASERS was 3/10 of the LD50 dose, which increased the MST and AST up to 54 and 49.5 days, respectively. Copyright © 2006 John Wiley & Sons, Ltd. [source] Anti-HIV-1 constituents from Clausena excavata: Part II. carbazoles and a pyranocoumarinPHYTOTHERAPY RESEARCH, Issue 8 2005Boonsong Kongkathip Abstract Three carbazole derivatives, O -methylmukonal (1), 3-formyl-2,7-dimethoxycarbazole (2) and clauszoline J (3), and a pyranocoumarin, clausenidin (4), were isolated from the rhizomes and roots of Clausena excavata. Compound 1, isolated from this plant for the first time, has not been reported previously as having anti-HIV-1 activity. Compounds 1,4 displayed anti-HIV-1 activity in a syncytial assay with EC50 values of 12, 29.1, 34.2 and 5.3 µm, respectively, and thus exhibited potential therapeutic index (PTI) values of 56.7, 8.0, 1.6 and 7.0, respectively. All isolated compounds demonstrated a lack of cytotoxicity against the KB and BC-1 cancer cell lines. Copyright © 2005 John Wiley & Sons, Ltd. [source] Nylon 66/clay nanocomposite structure development in a twin screw extruder,POLYMER ENGINEERING & SCIENCE, Issue 4 2009Bin Lin Nylon 66/clay nanocomposites were prepared in a Berstorff ZE25A UTX Ultra-glide corotating twin screw extruder at 270°C. Two types of extruder configurations with different mixing sections were used. One comprised two kneading block sections in the screws (KB only) and the other had a combination of a multi-process-element (MPE) section and a kneading block section. Samples at eight different locations along the extruder screw were obtained and analyzed using scanning electron microscope and transmission electron microscope to examine the morphology development of clay inside nylon down the length of the extruder. It is found that the clay aggregates are quickly broken into smaller tactoids (micron size) and then even much smaller clay bundles (nanometer size) and single clay platelets in the first mixing section. The structure changes in the second mixing section are much less significant. X-ray diffraction (XRD) analysis of the nanocomposite products showed small, or disappearance of, characteristic XRD (001) peaks, which indicates partial exfoliation, or complete exfoliation, respectively, of clay inside nylon matrix. Differential scanning calorimetry nonisothermal study shows that the crystallization temperature of the nanocomposites has increased around 17°C when compared with neat nylon 66. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers [source] Prevalence and Potential Risk Factors of Female Sexual Difficulties: An Urban Iranian Population-Based StudyTHE JOURNAL OF SEXUAL MEDICINE, Issue 11 2009Azita Goshtasebi MD ABTSRACT Introduction., Female sexual dysfunction is common, a multifactorial phenomenon with a potential to cause marital strain, impaired fertility, and poor quality of life. Epidemiologic data are scarce and little is known about the prevalence of sexual difficulties and the exact role of putative risk factors in Iran. Aim., To determine the prevalence of female sexual difficulties and the potential risk factors in an urban Iranian population. Methods., A cross-sectional study was performed in the province of Kohgilooyeh,Boyerahmad (KB) in the southwest of Iran and involved sexually active urban women aged 15 years and over, selected via a quota-based cluster sampling method. The study used an ad hoc questionnaire covering the demographic and reproductive variables as well as the data related to sexual difficulties. Data were analyzed using multiple logistic regression models. The main outcome measures were the prevalence rates and the predictors of sexual difficulties. Main Outcome Measures., The prevalence of female sexual difficulties and the associated risk factors. Results., One thousand four hundred fifty-six sexually active women living in the urban areas of KB province in 2005 were selected. The mean age of the sample was 34.04 ± 9.2 (16,71) years and the mean number of completed grades was 7.18 (±4.8). More than 52% of the participants had experienced at least one type of sexual difficulty. The greatest and smallest frequencies were observed for orgasm difficulty (21.3%, confidence interval[CI]0.95 = 19.2,23.4%) and lubrication difficulty (11.9%, CI0.95 = 10.2,13.6%). Age, education, contraceptive modality, and obstetric/gynecologic procedures were all associated with at least one type of sexual dysfunction. Conclusion., Similar to previous studies, we found a relatively high prevalence of sexual difficulties in this urban population of low socioeconomic status. However, our results concerning the role of some demographic and reproductive variables in producing sexual difficulties were different from those reported by other researchers. Goshtasebi A, Vahdaninia M, and Rahimi Foroshani A. Prevalence and potential risk factors of female sexual difficulties: An urban Iranian population-based study. J Sex Med 2009;6:2988,2996. [source] The Adventures of Huckleberry Finn: A Penguin Enriched eBook Classic,(Kindle Edition).THE MARK TWAIN ANNUAL, Issue 1 2009Introduction by John Seelye Format: Kindle Edition (1547 KB). 368 pp. Penguin Classics (2008). [source] Synthesis, characterization and in vitro antitumor activity of some arylantimony ferrocenecarboxylates and crystal structures of C5H5FeC5H4CO2SbPh4 and (C5H5FeC5H4CO2)2Sb(4-CH3C6H4)3APPLIED ORGANOMETALLIC CHEMISTRY, Issue 9 2003Run-Chang Liu Abstract A series of arylantimony ferrocenecarboxylates with the formula (C5H5FeC5H4CO2)nSbAr(5,n) (n = 1, 2; Ar = C6H5, 4-CH3C6H4, 3-CH3C6H4, 2-CH3C6H4, 4-ClC6H4, 4-FC6H4) were synthesized and characterized by elemental analysis, IR, 1H NMR and mass spectra. The crystal structures of (C5H5FeC5H4CO2)2Sb(4-CH3C6H4)3 and C5H5FeC5H4CO2SbPh4 were determined by X-ray diffraction. Four human neoplastic cell lines (HL-60, Bel-7402, KB and Hela) were used to screen these compounds. The results indicate that these compounds at 10 µM show certain in vitro antitumor activities. Copyright © 2003 John Wiley & Sons, Ltd. [source] Synthesis and in-vitro Cytotoxicity of Poly-functionalized 4-(2-Arylthiazol-4-yl)-4H -chromenesARCHIV DER PHARMAZIE, Issue 7 2010Majid Mahmoodi Abstract A new series of 4-aryl-4H -chromenes bearing a 2-arylthiazol-4-yl moiety at the 4-position were prepared as potential cytotoxic agents. The in-vitro cytotoxic activity of the synthesized 4-aryl-4H -chromenes was investigated in comparison with etoposide, a well-known anticancer drug, using MTT colorimetric assay. Among them, the 2-(2-chlorophenyl)thiazol-4-yl analog 4b showed the most potent activity against nasopharyngeal epidermoid carcinoma KB, medulloblastoma DAOY, and astrocytoma 1321N1, and compound 4d bearing a 2-(4-chlorophenyl)thiazol-4-yl moiety at the 4-position of the chromene ring exhibited the best inhibitory activity against breast cancer cells MCF-7, lung cancer cells A549, and colon adenocarcinoma cells SW480 with IC50 values less than 5 ,M. The ability of compound 4b to induce apoptosis was confirmed in a nuclear morphological assay by DAPI staining in the KB and MCF-7 cells. [source] Effect of Inoculum Composition and Low KCl Supplementation on the Biological and Rheological Stability of an Immobilized-Cell System for Mixed Mesophilic Lactic Starter ProductionBIOTECHNOLOGY PROGRESS, Issue 6 2001L. Lamboley Two strains of Lactococcus lactissubsp. lactis (L. lactis KB and KBP) and one of L. lactissubsp. lactis biovar. diacetylactis (L. diacetylactis MD) were immobilized separately in ,-carrageenan-locust bean gum gel beads. Continuous fermentations were carried out in supplemented whey permeate in a 1-L pH-controlled stirred tank reactor inoculated with a 30% (v/v) bead inoculum and a bead ratio of 55:30:15 for KB, KBP, and MD, respectively. The process demonstrated a high productivity and microbial stability during the 7-week continuous culture. Compared with previous experiments carried out with an inoculum bead ratio of 33:33:33 for KB, KBP, and MD beads, respectively, the modification of the inoculum bead ratio had apparently little effect on free and immobilized, total and specific populations. A dominant behavior of L. diacetylactis MD over the other strains of the mixed culture was observed both with free-cell populations in the effluent and with immobilized-cell populations. Additional experiments were carried out with other strain combinations for continuous inoculation-prefermentation of milk. The data also confirmed the dominance of L. diacetylactis during long-term continuous immobilized-cell fermentations. This dominance may be tentatively explained by the local competition involved in the development of the bead cross-contamination and in citrate utilization by L. diacetylactis strains. The gel beads demonstrated a high rheological stability during the 7-week continuous fermentation even at low KCl supplementation of the broth medium (25 mM KCl). [source] Self-Assembled Ionophores from Isoguanosine: Diffusion NMR Spectroscopy Clarifies Cation's and Anion's Influence on Supramolecular StructureCHEMISTRY - A EUROPEAN JOURNAL, Issue 7 2007Tamar Evan-Salem Abstract Cation-templated self-assembly of the lipophilic isoguanosine (isoG,1) with different monovalent cations (M+=Li+, Na+, K+, NH4+, and Cs+) was studied in solvents of different polarity by using diffusion NMR spectroscopy. Previous studies that did not use diffusion NMR techniques concluded that isoG,1 forms both pentamers (isoG,1)5,M+ and decamers (isoG,1)10,M+ in the presence of alkali-metal cations. The present diffusion NMR studies demonstrate, however, that isoG,1 does not form (isoG,1)5,M+ pentamers. In fact, the diffusion NMR data indicates that both doubly charged decamers of formula (isoG,1)10,2,M+ and singly charged decamers, (isoG,1)10,M+, are formed with lithium, sodium, potassium, and ammonium tetraphenylborate salts (LiB(Ph)4, KB(Ph)4, NaB(Ph)4 and NH4B(Ph)4), depending on the isoG,1:salt stoichiometry of the solution. In the presence of CsB(Ph)4, isoG,1 affords only the singly charged decamers (isoG,1)10,Cs+. By monitoring the diffusion coefficient of the B(Ph)4, ion in the different mixtures of solvents, we also concluded that the anion is more strongly associated to the doubly charged decamers (isoG,1)10,2,M+ than to the singly charged decamers (isoG,1)10,M+. The (isoG,1)10,2,M+ species can, however, exist in solution without the mediation of the anion. This last conclusion was supported by the finding that the doubly charged decamers (isoG,1)10,2,M+ also prevail in 1:1 CD3CN:CDCl3, a solvent mixture in which the B(Ph)4, ion does not interact significantly with the self-assembled complex. These diffusion measurements, which have provided new and improved structural information about these decameric isoG,1 assemblies, demonstrate the utility of combining diffusion NMR techniques with conventional NMR methods in seeking to characterize labile, multicomponent, supramolecular systems in solution, especially those with high symmetry. [source] Study of Antimalarial Activity of Chemical Constituents from Diospyros quaesitaCHEMISTRY & BIODIVERSITY, Issue 11 2008Cui-Ying Ma Abstract Bioassay-directed fractionation led to the isolation of seven compounds from a sample of the dried leaves, twigs, and branches of Diospyros quaesitaThw. (Ebenaceae). One of the isolates, betulinic acid 3-caffeate (1), showed in vitro antimalarial activity against Plasmodium falciparum clones D6 (chloroquine-sensitive) and W2 (chloroquine-resistant) with IC50 values of 1.40 and 0.98,,M, respectively. Evaluation of compound 1 in the human oral epidermoid (KB) cancer cell line revealed cytotoxicity at ED50 of 4.0,,M. In an attempt to reduce the cytotoxicity of 1, the acetylated derivative 1a and betulinic acid (1b) were prepared. Of the seven isolates, diospyrosin (2) was determined to be a new neolignan. In addition to 1, other known compounds isolated in this study were pinoresinol, lariciresinol, N -benzoyl- L -phenylalaninol, scopoletin, and poriferast-5-en-3,,7, -diol. The structure of 2 was elucidated based on spectroscopic data analysis including 1D- and 2D-NMR, and HR-ESI-MS. [source] Synthesis, Antiproliferative Evaluation, and Structure,Activity Relationships of 3-ArylquinolinesCHEMMEDCHEM, Issue 10 2008Zhu-Ping Xiao The cytotoxicity of substituted 3-aryl-4-chloroquinolines: A series of 3-arylquinolines were designed, synthesized and evaluated as antitumor agents. While the majority of the 34 compounds evaluated exhibited potent cytotoxicity in one or more of the human tumor cell lines tested, two compounds were identified as potential leads, with high activity against human hepatocellular liver carcinoma (Hep-G2), human erythromyeloblastoid leukemia (K562) and human oral epidermoid carcinoma (KB) cell lines, and lacking significant cytotoxicity against the normal human liver cell line (L02). [source] Structure, DNA Binding Studies and Cytotoxicity of Complex [Pd(phen)(L -asp)]·3H2OCHINESE JOURNAL OF CHEMISTRY, Issue 6 2009Enjun GAO Abstract The palladium(II) complex of [Pd(phen)(L -asp)]·3H2O (phen=1,10-phenanthroline, H2L-asp=L -aspartic acid) has been synthesized from a solution reaction and analyzed by elemental analyses, 1H NMR and IR spectra. Moreover, the complex has been structurally characterized by single-crystal X-ray diffractometry. The cytotoxicity assay of the complex and cis -DDP as reference substance against three different cancer cell lines (Hela, Hep-G2 and KB) has been conducted. The results show that the Pd complex exhibits higher cytotoxicity against Hela system. The study on the interaction of the Pd complex with fish sperm DNA (FS-DNA) has been performed with diverse spectroscopic techniques, showing that the complex is bound to the fish sperm DNA via an intercalative mode. Gel electrophoresis assay demonstrates the ability of the complex to cleave the pBR 322 plasmid DNA. [source] Resolution, configurational assignment, and enantiopharmacology at glutamate receptors of 2-amino-3-(3-carboxy-5-methyl-4-isoxazolyl)propionic acid (ACPA) and demethyl-ACPA,CHIRALITY, Issue 9 2001Tommy N. Johansen Abstract We have previously described (RS)-2-amino-3-(3-carboxy-5-methyl-4-isoxazolyl)propionic acid (ACPA) as a potent agonist at the (RS)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA) receptor subtype of (S)-glutamic acid (Glu) receptors. We now report the chromatographic resolution of ACPA and (RS)-2-amino-3-(3-carboxy-4-isoxazolyl)propionic acid (demethyl-ACPA) using a Sumichiral OA-5000 column. The configuration of the enantiomers of both compounds have been assigned based on X-ray crystallographic analyses, supported by circular dichroism spectra and elution orders on chiral HPLC columns. Furthermore, the enantiopharmacology of ACPA and demethyl-ACPA was investigated using radioligand binding and cortical wedge electrophysiological assay systems and cloned metabotropic Glu receptors. (S)-ACPA showed high affinity in AMPA binding (IC50 = 0.025 ,M), low affinity in kainic acid binding (IC50 = 3.6 ,M), and potent AMPA receptor agonist activity on cortical neurons (EC50 = 0.25 ,M), whereas (R)-ACPA was essentially inactive. Like (S)-ACPA, (S)-demethyl-ACPA displayed high AMPA receptor affinity (IC50 = 0.039 ,M), but was found to be a relatively weak AMPA receptor agonist (EC50 = 12 ,M). The stereoselectivity observed for demethyl-ACPA was high when based on AMPA receptor affinity (eudismic ratio = 250), but low when based on electrophysiological activity (eudismic ratio = 10). (R)-Demethyl-ACPA also possessed a weak NMDA receptor antagonist activity (IC50 = 220 ,M). Among the enantiomers tested, only (S)-demethyl-ACPA showed activity at metabotropic receptors, being a weak antagonist at the mGlu2 receptor subtype (KB = 148 ,M). Chirality 13:523,532, 2001. © 2001 Wiley-Liss, Inc. [source] Human and pig SRY 5, flanking sequences can direct reporter transgene expression to the genital ridge and to migrating neural crest cellsDEVELOPMENTAL DYNAMICS, Issue 3 2006Alexandre Boyer Abstract Mechanisms for sex determination vary greatly between animal groups, and include chromosome dosage and haploid,diploid mechanisms as seen in insects, temperature and environmental cues as seen in fish and reptiles, and gene-based mechanisms as seen in birds and mammals. In eutherian mammals, sex determination is genetic, and SRY is the Y chromosome located gene representing the dominant testes determining factor. How SRY took over this function from ancestral mechanisms is not known, nor is it known what those ancestral mechanisms were. What is known is that SRY is haploid and thus poorly protected from mutations, and consequently is poorly conserved between mammalian species. To functionally compare SRY promoter sequences, we have generated transgenic mice with fluorescent reporter genes under the control of various lengths of human and pig SRY 5, flanking sequences. Human SRY 5, flanking sequences (5 Kb) supported reporter transgene expression within the genital ridge of male embryos at the time of sex determination and also supported expression within migrating truncal neural crest cells of both male and female embryos. The 4.6 Kb of pig SRY 5, flanking sequences supported reporter transgene expression within the male genital ridge but not within the neural crest; however, 2.6 Kb and 1.6 Kb of pig SRY 5, flanking sequences retained male genital ridge expression and now supported extensive expression within cells of the neural crest in embryos of both sexes. When 2 Kb of mouse SRY 5, flanking sequences (,3 to ,1 Kb) were placed in front of the 1.6 Kb of pig SRY 5, flanking sequences and this transgene was introduced into mice, reporter transgene expression within the male genital ridge was retained but neural crest expression was lost. These observations suggest that SRY 5, flanking sequences from at least two mammalian species contain elements that can support transgene expression within cells of the migrating neural crest and that additional SRY 5, flanking sequences can extinguish this expression. Developmental Dynamics 235:623,632, 2006. © 2006 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||||||||||||||||||||