44 results on '"Fleischer TC"'
Search Results
2. Antibacterial, Antioxidant and Anti-inflammatory Properties of Margaritaria discoidea, a Wound Healing Remedy from Ghana
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Dickson, RA, Fleischer, TC, Ekuadzi, E, Mensah, AY, Annan, K, and Woode, E
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- 2010
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3. Effectiveness And Safety Assessment Of Mist tonica, A Herbal Haematinic
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Adusi-Poku, Y, Sittie, A, Mensah, MLK, Sarpong, K, Fleischer, TC, Ankrah, TC, and Nsiah, D
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Anaemia, haemoglobin, herbal, haematinic, safety, effectiveness - Abstract
Anaemia is a widespread public health problem, and in Ghana it is the fourth leading cause of hospital admissions and the second factor contributing to death. Mist Tonica, an herbal haematinic produced by the Centre for Scientific Research into Plant Medicine (CSRPM), Ghana, was assessed for its effectiveness and safety in humans after Ethics Committee approval. Clinically established anaemic-patients aged, 13 years and above, with haemoglobin levels less than 11.5 g/dl and 13.5g/dl for females and males respectively were treated with Mist tonica, 8.96 g/ 40 mls three times daily for two weeks . The mean haemoglobin rise per week caused by Mist Tonica was 1.92 (0.76) g/dl, range (1.66 - 2.55) g/dl/week and over 88 % of the patients on Mist Tonica had their appetite for food improved. Haematological profile, liver and kidney functions were not adversely affected by Mist tonica. Results of the study suggest that Mist Tonica is an effective and safe herbal haematinic. Keywords: Anaemia, haemoglobin, herbal, haematinic, safety, effectivenessAfr. Jnl of Trad Comp Alt medicine Vol. 5 (2) 2008: pp. 115-119
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- 2008
4. Antimicrobial Activity of Essential Oils of Xylopia Aethiopica
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Fleischer, TC, Mensah, MLK, Mensah, AY, Komlaga, G, Gbedema, SY, and Skaltsa, H
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Research Communication ,fungi ,Xylopia aethiopica, Annonaceae, Essential oils, Antimicrobial activity - Abstract
Xylopia aethiopica is a medicinal plant of great repute in West Africa which produces a variety of complex chemical compounds. The fresh and dried fruits, leaf, stem bark and root bark essential oils showed various degrees of activity against the Gram positive bacteria, Bacillus subtilis and Staphylococcus aureus, the Gram negative bacteria Pseudomonas aeruginosa and the yeast-like fungus Candida albicans, using the cup plate method,. However, none of the oils showed activity against Escherichia coli.. Keywords:Xylopia aethiopica, Annonaceae, Essential oils, Antimicrobial activity.African Journal of Trad, Comp and Alternative Medicine Vol. 5 (4) 2008: pp. 391-393
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- 2008
5. Anti-Inflammatory, Antioxidant, and Selective Antibacterial Effects of Euadenia eminens Root Bark
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Dickson, RA, primary, Fleischer, TC, additional, Ekuadzi, E, additional, and Komlaga, G, additional
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- 2012
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6. Hypoglycaemic and Antioxidant Activities of the Stem Bark of Morinda Lucida Benth in Streptozotocin – Induced Diabetic Rats
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Fleischer, TC, primary, Sarkodie, JA, additional, Komlaga, G, additional, Kuffour, G, additional, Dickson, RA, additional, and Mensah, MLK, additional
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- 2011
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7. Cassane-type diterpenoids from the genus Caesalpinia
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Dickson, RA, primary, Fleischer, TC, additional, and Houghton, Peter, additional
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- 2011
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8. ANTI-INFLAMMATORY AND ANTIOXIDANT ACTIVITIES OF THE LEAVES OF WISSADULA AMPLISSIMA VAR ROSTRATA
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Mensah, AY, primary, Donkor, PO, additional, and Fleischer, TC, additional
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- 2011
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9. Antimicrobial Activity Of Essential Oils Of Xylopia aethiopica
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Fleischer, TC, primary, Mensah, MLK, additional, Mensah, AY, additional, Komlaga, G, additional, Gbedema, SY, additional, and Skaltsa, H, additional
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- 2008
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10. Effects of Tetrapleura Tetraptera (Taub) Fruit Extract On Some Isolated Tissues: Possible Mechanism(S) of Antihypertensive Action
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Woode, E, primary, Amissah, F, additional, Duwiejua, M, additional, Ansah, C, additional, Fleischer, TC, additional, and Sawer, IK, additional
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- 2008
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11. Flavonoid constituents of the mature fruit of Tetrapleura tetraptera schum. Et Thonn.)
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Fleischer, TC, primary, Komlaga, G, additional, Mensah, AY, additional, Mensah, MLK, additional, Wood, E, additional, Sawer, IK, additional, and Grey, AI, additional
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- 2006
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12. Ethno-Botanical Survey Of Medicinal Plants In The Plant Genetic Resources Centre Arboretum – Bunso
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Boateng, SK, primary, Bennett-Lartey, SO, additional, Opolu-Agyeman, MO, additional, Mensah, MLK, additional, and Fleischer, TC, additional
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- 2005
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13. Validating the ratio of insulin like growth factor binding protein 4 to sex hormone binding globulin as a prognostic predictor of preterm birth in Viet Nam: a case-cohort study.
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Hirst JE, Boniface JJ, Le DP, Polpitiya AD, Fox AC, Vu TTK, Dang TT, Fleischer TC, Bui NTH, Hickok DE, Kearney PE, Thwaites G, Kennedy SH, Kestelyn E, and Le TQ
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- Pregnancy, Infant, Newborn, Humans, Female, Young Adult, Adult, Cohort Studies, Insulin-Like Peptides, Prognosis, Sex Hormone-Binding Globulin, Vietnam epidemiology, Gestational Age, Biomarkers, Premature Birth epidemiology, Premature Birth diagnosis
- Abstract
Objective: To validate a serum biomarker developed in the USA for preterm birth (PTB) risk stratification in Viet Nam., Methods: Women with singleton pregnancies ( n = 5000) were recruited between 19
+0 -23+6 weeks' gestation at Tu Du Hospital, Ho Chi Minh City. Maternal serum was collected from 19+0 -22+6 weeks' gestation and participants followed to neonatal discharge. Relative insulin-like growth factor binding protein 4 (IGFBP4) and sex hormone binding globulin (SHBG) abundances were measured by mass spectrometry and their ratio compared between PTB cases and term controls. Discrimination (area under the receiver operating characteristic curve, AUC) and calibration for PTB <37 and <34 weeks' gestation were tested, with model tuning using clinical factors. Measured outcomes included all PTBs (any birth ≤37 weeks' gestation) and spontaneous PTBs (birth ≤37 weeks' gestation with clinical signs of initiation of parturition)., Results: Complete data were available for 4984 (99.7%) individuals. The cohort PTB rate was 6.7% ( n = 335). We observed an inverse association between the IGFBP4/SHBG ratio and gestational age at birth ( p = 0.017; AUC 0.60 [95% CI, 0.53-0.68]). Including previous PTB (for multiparous women) or prior miscarriage (for primiparous women) improved performance (AUC 0.65 and 0.70, respectively, for PTB <37 and <34 weeks' gestation). Optimal performance (AUC 0.74) was seen within 19-20 weeks' gestation, for BMI >21 kg/m2 and age 20-35 years., Conclusion: We have validated a novel serum biomarker for PTB risk stratification in a very different setting to the original study. Further research is required to determine appropriate ratio thresholds based on the prevalence of risk factors and the availability of resources and preventative therapies.- Published
- 2024
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14. Performance of a validated spontaneous preterm delivery predictor in South Asian and Sub-Saharan African women: a nested case control study.
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Khanam R, Fleischer TC, Boghossian NS, Nisar I, Dhingra U, Rahman S, Fox AC, Ilyas M, Dutta A, Naher N, Polpitiya AD, Mehmood U, Deb S, Choudhury AA, Badsha MB, Muhammad K, Ali SM, Ahmed S, Hickok DE, Iqbal N, Juma MH, Quaiyum MA, Boniface JJ, Yoshida S, Manu A, Bahl R, Jehan F, Sazawal S, Burchard J, and Baqui AH
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- Infant, Newborn, Female, Humans, Case-Control Studies, Artificial Intelligence, Prospective Studies, Biomarkers, Africa South of the Sahara, Premature Birth diagnosis
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Objectives: To address the disproportionate burden of preterm birth (PTB) in low- and middle-income countries, this study aimed to (1) verify the performance of the United States-validated spontaneous PTB (sPTB) predictor, comprised of the IBP4/SHBG protein ratio, in subjects from Bangladesh, Pakistan and Tanzania enrolled in the Alliance for Maternal and Newborn Health Improvement (AMANHI) biorepository study, and (2) discover biomarkers that improve performance of IBP4/SHBG in the AMANHI cohort., Study Design: The performance of the IBP4/SHBG biomarker was first evaluated in a nested case control validation study, then utilized in a follow-on discovery study performed on the same samples. Levels of serum proteins were measured by targeted mass spectrometry. Differences between the AMANHI and U.S. cohorts were adjusted using body mass index (BMI) and gestational age (GA) at blood draw as covariates. Prediction of sPTB < 37 weeks and < 34 weeks was assessed by area under the receiver operator curve (AUC). In the discovery phase, an artificial intelligence method selected additional protein biomarkers complementary to IBP4/SHBG in the AMANHI cohort., Results: The IBP4/SHBG biomarker significantly predicted sPTB < 37 weeks ( n = 88 vs. 171 terms ≥ 37 weeks) after adjusting for BMI and GA at blood draw (AUC= 0.64, 95% CI: 0.57-0.71, p < .001). Performance was similar for sPTB < 34 weeks ( n = 17 vs. 184 ≥ 34 weeks): AUC = 0.66, 95% CI: 0.51-0.82, p = .012. The discovery phase of the study showed that the addition of endoglin, prolactin, and tetranectin to the above model resulted in the prediction of sPTB < 37 with an AUC= 0.72 (95% CI: 0.66-0.79, p -value < .001) and prediction of sPTB < 34 with an AUC of 0.78 (95% CI: 0.67-0.90, p < .001)., Conclusion: A protein biomarker pair developed in the U.S. may have broader application in diverse non-U.S. populations.
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- 2022
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15. Metabolite profiling, antifungal, biofilm formation prevention and disruption of mature biofilm activities of Erythrina senegalensis stem bark extract against Candida albicans and Candida glabrata.
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Harley BK, Quagraine AM, Neglo D, Aggrey MO, Orman E, Mireku-Gyimah NA, Amengor CD, Jato J, Saaka Y, and Fleischer TC
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- Candida albicans, Antifungal Agents pharmacology, Fluconazole, Nystatin pharmacology, Plant Bark, Biofilms, Candida, Plant Extracts pharmacology, Candida glabrata, Erythrina
- Abstract
The antifungal activity of the 70% ethanol stem bark extract of Erythrina senegalensis (ESB) against different strains and drug resistant clinical isolates of Candida albicans and Candida glabrata were evaluated in the study. The effect of ESB on biofilms as well as its activity in combination with fluconazole, nystatin or caspofungin against the Candida strains were also evaluated. We then evaluated the antifungal activity of a microemulsion formulation of ESB against planktonic and biofilms of the Candida species. UPLC-QTOF-MS2 analysis was then undertaken to identify the phytoconstituents of the extract and UPLC fingerprints developed for the routine authentication as part of quality control measures. ESB exerted strong antifungal activities against C. albicans ATCC 10231 and SC5314 strains, and C. glabrata ATCC 2001 strain with minimum inhibitory concentration (MIC) values from 3.91 to 31.25 μg/mL and minimum fungicidal concentrations (MFCs) that ranged from 62.5 to 250 μg/mL. It also exhibited potent antifungal activities (MIC = 4-64 μg/mL) against a collection of C. albicans and C. glabrata clinical isolates that were resistant to either nystatin or azole antifungals. The formulated ESB demonstrated higher antifungal potency against the C. albicans and C. glabrata strains with MIC values of 3.91-31.25 μg/mL which was the same as the MFC values. The extract and its microemulsion formulation were active against biofilms of the strains of the Candida species inhibiting their biofilm formations (SMIC50 = 16-64 μg/mL) and their preformed biofilms (SMIC50 = 128 ->512 μg/mL). ESB also exhibited synergistic antifungal action with fluconazole and nystatin against C. albicans ATCC 10231 and C. glabrata ATCC 2001 strains in the checkerboard assay. Chemical characterization of the extract revealed the presence of phenolic compounds such as flavonoids and their prenylated derivatives, anthracene glycosides and alkaloids. UPLC Fingerprints of the extract was also developed and validated for routine identification and authentication of the stem bark of E. senegalensis. The study findings have demonstrated that the stem bark of E. senegalensis is as a potential source of bioactive compounds that could be developed as novel antifungal agents., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Harley et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2022
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16. Corrigendum to "Analytical validation of protein biomarkers for risk of spontaneous preterm birth" [Clin. Mass Spectrom. 3 (2017) 25-38].
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Bradford C, Severinsen R, Pugmire T, Rasmussen M, Stoddard K, Uemura Y, Wheelwright S, Mentinova M, Chelsky D, Hunsucker SW, Kearney P, Hickok D, Fleischer TC, Ichetovkin I, Boniface JJ, Critchfield GC, and Peltier JM
- Abstract
[This corrects the article DOI: 10.1016/j.clinms.2017.06.002.]., (© 2022 THE AUTHORS. Publishing services by ELSEVIER B.V. on behalf of MSACL.)
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- 2022
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17. Antifungal Activities of Phytochemically Characterized Hydroethanolic Extracts of Sclerocarya birrea Leaves and Stem Bark against Fluconazole-Resistant Candida albicans Strains.
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Harley BK, Neglo D, Aggrey MO, Quagraine AM, Orman E, Jato J, Mireku-Gyimah NA, Amengor CDK, and Fleischer TC
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- Candida albicans, Flavonoids pharmacology, Fluconazole pharmacology, Microbial Sensitivity Tests, Plant Bark chemistry, Plant Extracts chemistry, Tandem Mass Spectrometry, Anacardiaceae chemistry, Antifungal Agents analysis
- Abstract
The study evaluated the antifungal activities of the 70% ethanol extracts of Sclerocarya birrea leaves (SBL) and stem bark (SBB) against C. albicans strains and fluconazole-resistant isolates, their antifungal effects in combination with conventional antifungals as well as their effects on the biofilms of the C. albicans strains and isolates. UPLC-QTOF-MS/MS analysis was then carried out to investigate the metabolite profile of the extracts and UPLC fingerprints developed for their routine identification as part of quality control measures. The extracts exhibited considerable antifungal activity with MIC ranging from 12.21 to 97.66 μ g/mL and MFC from 12.21 to 390.63 μ g/mL against the C. albicans strains and isolates. The antifungal activity of the stem bark extract was higher than the leaf extract. SBL and SBB also significantly inhibited biofilm formation (IC
50 = 12.49 to 164.42 μ g/mL) and the mature biofilms (IC50 = 91.50 to 685.20 μ g/mL) of the strains and isolates of the C. albicans and demonstrated potential for their use in combination therapies with currently used antifungals especially the stem bark extract with nystatin. Metabolite profiling identified the presence of polyphenolic compounds in both leaves and stem bark mostly flavonoids, their derivatives, and proanthocyanidins, which contribute in part to the bioactivity of the plant. Whereas flavonoids like quercetin, myricetin, and their derivatives were abundant in the leaves, epicatechin monomers with their condensed tannins, including procyanidin B2 and procyanidin C, were abundant in the stem bark. Fingerprints of SBL and SBB were developed and validated and could be used as qualitative tools to authenticate the plant. The outcomes of the study show the promise of the leaf and stem bark extracts of S. birrea to be studied further and developed as antifungal agents., Competing Interests: The authors declare no conflict of interest., (Copyright © 2022 Benjamin Kingsley Harley et al.)- Published
- 2022
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18. Better Estimation of Spontaneous Preterm Birth Prediction Performance through Improved Gestational Age Dating.
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Burchard J, Saade GR, Boggess KA, Markenson GR, Iams JD, Coonrod DV, Pereira LM, Hoffman MK, Polpitiya AD, Treacy R, Fox AC, Randolph TL, Fleischer TC, Dufford MT, Garite TJ, Critchfield GC, Boniface JJ, and Kearney PE
- Abstract
The clinical management of pregnancy and spontaneous preterm birth (sPTB) relies on estimates of gestational age (GA). Our objective was to evaluate the effect of GA dating uncertainty on the observed performance of a validated proteomic biomarker risk predictor, and then to test the generalizability of that effect in a broader range of GA at blood draw. In a secondary analysis of a prospective clinical trial (PAPR; NCT01371019), we compared two GA dating categories: both ultrasound and dating by last menstrual period (LMP) (all subjects) and excluding dating by LMP (excluding LMP). The risk predictor's performance was observed at the validated risk predictor threshold both in weeks 19
1/7 -206/7 and extended to weeks 180/7 -206/7 . Strict blinding and independent statistical analyses were employed. The validated biomarker risk predictor showed greater observed sensitivity of 88% at 75% specificity (increases of 17% and 1%) in more reliably dated (excluding-LMP) subjects, relative to all subjects. Excluding dating by LMP significantly improved the sensitivity in weeks 191/7 -206/7 . In the broader blood draw window, the previously validated risk predictor threshold significantly stratified higher and lower risk of sPTB, and the risk predictor again showed significantly greater observed sensitivity in excluding-LMP subjects. These findings have implications for testing the performance of models aimed at predicting PTB.- Published
- 2022
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19. Hypoglycaemic activity of Oleanonic acid, a 3-oxotriterpenoid isolated from Aidia Genipiflora (DC.) Dandy, involves inhibition of carbohydrate metabolic enzymes and promotion of glucose uptake.
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Harley BK, Amponsah IK, Ben IO, Mireku-Gyimah NA, Anokwah D, Neglo D, Amengor CDK, and Fleischer TC
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- Animals, Blood Glucose metabolism, Hypoglycemic Agents adverse effects, Plant Extracts adverse effects, Rats, Streptozocin adverse effects, Triterpenes, alpha-Amylases, Diabetes Mellitus, Experimental, Rubiaceae
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The present study evaluated the antidiabetic activities of the 70% ethanol stem bark extract of Aidia genipiflora (AGB) and one of its constituents, oleanonic acid in streptozotocin (40 mg/kg)-induced diabetic rats. In vitro assays of glucose uptake and inhibition of carbohydrate metabolizing enzymes were then used to investigate their mechanism(s) of hypoglycaemic action. In silico evaluation of the pharmacokinetic and toxicity properties of the compound was also carried out. Administration of AGB (100-400 mg/kg) and oleanonic acid (15 - 60 mg/kg) resulted in significant reductions (p < 0.001) in the blood glucose and considerable decrease (p < 0.05) in the elevated lipid parameters of the diabetic animals. AGB activity at 200 and 400 mg/kg; and oleanonic acid at 60 mg/kg were comparable to glibenclamide (5 mg/kg). The extract and its isolate strongly inhibited α-glucosidase and α-amylase activity with IC
50 values of (10.48 ± 1.39 µg/mL and 14.51 ± 1.26 µg/mL) and (36.52 ± 1.95 µM and 105.84 ± 1.08 µM) respectively. The glucose uptake assays showed that AGB and oleanonic acid exerted both insulin-dependent and independent promotional effect of glucose transport into the periphery by upregulating the expression of PI3K and PPARγ transcripts with a concomitant increase in GLUT-4 transcripts. Although oleanonic acid was predicted to be teratogenic, it was found to be generally non-lethal with favourable pharmacokinetics properties making it suitable for further studies. The study has shown that the stem bark of A. genipiflora is a source of new hypoglycaemic agents and that oleanonic acid possesses hypoglycaemic and anti-hyperlipidaemic activities., (Copyright © 2022 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)- Published
- 2022
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20. Clinical and economic evaluation of a proteomic biomarker preterm birth risk predictor: cost-effectiveness modeling of prenatal interventions applied to predicted higher-risk pregnancies within a large and diverse cohort.
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Burchard J, Markenson GR, Saade GR, Laurent LC, Heyborne KD, Coonrod DV, Schoen CN, Baxter JK, Haas DM, Longo SA, Sullivan SA, Wheeler SM, Pereira LM, Boggess KA, Hawk AF, Crockett AH, Treacy R, Fox AC, Polpitiya AD, Fleischer TC, Garite TJ, Jay Boniface J, Zupancic JAF, Critchfield GC, and Kearney PE
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- Pregnancy, Female, Infant, Newborn, Humans, Cost-Benefit Analysis, Proteomics, Gestational Age, Biomarkers, Premature Birth prevention & control
- Abstract
Objectives: Preterm birth occurs in more than 10% of U.S. births and is the leading cause of U.S. neonatal deaths, with estimated annual costs exceeding $25 billion USD. Using real-world data, we modeled the potential clinical and economic utility of a prematurity-reduction program comprising screening in a racially and ethnically diverse population with a validated proteomic biomarker risk predictor, followed by case management with or without pharmacological treatment., Methods: The ACCORDANT microsimulation model used individual patient data from a prespecified, randomly selected sub-cohort ( N = 847) of a multicenter, observational study of U.S. subjects receiving standard obstetric care with masked risk predictor assessment (TREETOP; NCT02787213). All subjects were included in three arms across 500 simulated trials: standard of care (SoC, control); risk predictor/case management comprising increased outreach, education and specialist care (RP-CM, active); and multimodal management (risk predictor/case management with pharmacological treatment) (RP-MM, active). In the active arms, only subjects stratified as higher risk by the predictor were modeled as receiving the intervention, whereas lower-risk subjects received standard care. Higher-risk subjects' gestational ages at birth were shifted based on published efficacies, and dependent outcomes, calibrated using national datasets, were changed accordingly. Subjects otherwise retained their original TREETOP outcomes. Arms were compared using survival analysis for neonatal and maternal hospital length of stay, bootstrap intervals for neonatal cost, and Fisher's exact test for neonatal morbidity/mortality (significance, p < .05)., Results: The model predicted improvements for all outcomes. RP-CM decreased neonatal and maternal hospital stay by 19% ( p = .029) and 8.5% ( p = .001), respectively; neonatal costs' point estimate by 16% ( p = .098); and moderate-to-severe neonatal morbidity/mortality by 29% ( p = .025). RP-MM strengthened observed reductions and significance. Point estimates of benefit did not differ by race/ethnicity., Conclusions: Modeled evaluation of a biomarker-based test-and-treat strategy in a diverse population predicts clinically and economically meaningful improvements in neonatal and maternal outcomes.
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- 2022
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21. Bioactive triterpenoids from Solanum torvum fruits with antifungal, resistance modulatory and anti-biofilm formation activities against fluconazole-resistant candida albicans strains.
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Harley BK, Neglo D, Tawiah P, Pipim MA, Mireku-Gyimah NA, Tettey CO, Amengor CD, Fleischer TC, and Waikhom SD
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- Antifungal Agents chemistry, Antifungal Agents isolation & purification, Biofilms drug effects, Candida albicans drug effects, Microbial Sensitivity Tests, Plant Extracts isolation & purification, Plant Extracts pharmacology, Triterpenes chemistry, Triterpenes isolation & purification, Antifungal Agents pharmacology, Biofilms growth & development, Candida albicans physiology, Drug Resistance, Fungal drug effects, Fluconazole pharmacology, Fruit chemistry, Solanum chemistry, Triterpenes pharmacology
- Abstract
Vulvovaginal candidiasis (VVC) is the second most common vaginal infection that affects women of reproductive age. Its increased occurrence and associated treatment cost coupled to the rise in resistance of the causative pathogen to current antifungal therapies has necessitated the need for the discovery and development of novel effective antifungal agents for the treatment of the disease. We report in this study the anti-Candida albicans activity of Solanum torvum 70% ethanol fruit extract (STF), fractions and some isolated compounds against four (4) fluconazole-resistant strains of C. albicans. We further report on the effect of the isolated compounds on the antifungal activity of fluconazole and voriconazole in the resistant isolates as well as their inhibitory effect on C. albicans biofilm formation. STF was fractionated using n-hexane, chloroform (CHCl3) and ethyl acetate (EtOAc) to obtain four respective major fractions, which were then evaluated for anti-C. albicans activity using the microbroth dilution method. The whole extract and fractions recorded MICs that ranged from 0.25 to 16.00 mg/mL. From the most active fraction, STF- CHCl3 (MIC = 0.25-1.00 mg/mL), four (4) known compounds were isolated as Betulinic acid, 3-oxo-friedelan-20α-oic acid, Sitosterol-3-β-D-glucopyranoside and Oleanolic acid. The compounds demonstrated considerably higher antifungal activity (0.016 to 0.512 mg/mL) than the extract and fractions and caused a concentration-dependent anti-biofilm formation activity. They also increased the sensitivity of the C. albicans isolates to fluconazole. This is the first report of 3-oxo-friedelan-20α-oic acid in the plant as well as the first report of betulinic acid, sitosterol-3-β-D-glucopyranoside and oleanolic acid from the fruits of S. torvum. The present study has demonstrated the anti-C. albicans activity of the constituents of S. torvum ethanol fruit extract and also shown that the constituents possess anti-biofilm formation and resistance modulatory activities against fluconazole-resistant clinical C. albicans isolates., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2021
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22. Clinical Validation of a Proteomic Biomarker Threshold for Increased Risk of Spontaneous Preterm Birth and Associated Clinical Outcomes: A Replication Study.
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Burchard J, Polpitiya AD, Fox AC, Randolph TL, Fleischer TC, Dufford MT, Garite TJ, Critchfield GC, Boniface JJ, Saade GR, and Kearney PE
- Abstract
Preterm births are the leading cause of neonatal death in the United States. Previously, a spontaneous preterm birth (sPTB) predictor based on the ratio of two proteins, IBP4/SHBG, was validated as a predictor of sPTB in the Proteomic Assessment of Preterm Risk (PAPR) study. In particular, a proteomic biomarker threshold of -1.37, corresponding to a ~two-fold increase or ~15% risk of sPTB, significantly stratified earlier deliveries. Guidelines for molecular tests advise replication in a second independent study. Here we tested whether the significant association between proteomic biomarker scores above the threshold and sPTB, and associated adverse outcomes, was replicated in a second independent study, the Multicenter Assessment of a Spontaneous Preterm Birth Risk Predictor (TREETOP). The threshold significantly stratified subjects in PAPR and TREETOP for sPTB ( p = 0.041, p = 0.041, respectively). Application of the threshold in a Kaplan-Meier analysis demonstrated significant stratification in each study, respectively, for gestational age at birth ( p < 001, p = 0.0016) and rate of hospital discharge for both neonate ( p < 0.001, p = 0.005) and mother ( p < 0.001, p < 0.001). Above the threshold, severe neonatal morbidity/mortality and mortality alone were 2.2 ( p = 0.0083,) and 7.4-fold higher ( p = 0.018), respectively, in both studies combined. Thus, higher predictor scores were associated with multiple adverse pregnancy outcomes.
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- 2021
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23. Myrianthus libericus: Possible mechanisms of hypoglycaemic action and in silico prediction of pharmacokinetics and toxicity profile of its bioactive metabolite, friedelan-3-one.
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Harley BK, Amponsah IK, Ben IO, Adongo DW, Mireku-Gyimah NA, Baah MK, Mensah AY, and Fleischer TC
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- Animals, Cell Line, Computer Simulation, Diabetes Mellitus, Experimental drug therapy, Glucose metabolism, Glucose Transporter Type 4 metabolism, Glyburide pharmacology, Hypoglycemic Agents pharmacokinetics, Hypoglycemic Agents toxicity, Lipid Metabolism drug effects, Male, Muscle Fibers, Skeletal drug effects, Muscle Fibers, Skeletal metabolism, PPAR gamma biosynthesis, Phosphatidylinositol 3-Kinases biosynthesis, Plant Bark chemistry, Rats, Rats, Sprague-Dawley, Triterpenes pharmacokinetics, Triterpenes toxicity, Up-Regulation, alpha-Amylases antagonists & inhibitors, Hypoglycemic Agents pharmacology, Triterpenes pharmacology, Urticaceae chemistry
- Abstract
The hypoglycaemic and anti-hyperlipidaemic effects of the 70% ethanol stem bark extract of Myrianthus libericus (MLB), used traditionally in the management of diabetes in Ghana, was evaluated in this study using streptozotocin (45 mg/kg)-induced diabetic rats. In vitro hypoglycaemic activities of the extract and one of its principal compounds, friedelan-3-one were then investigated using α-amylase inhibitory and glucose uptake assay in C2C12 myotubes. In silico analysis of the pharmacokinetic and toxicity properties of the compound was also performed. MLB significantly (p < 0.001) reduced the elevated blood glucose levels and corrected considerably (p < 0.01) the altered serum lipid profiles of the diabetic rats which was comparable to glibenclamide (5 mg/kg). Together with friedelan-3-one, the extract markedly inhibited the activity of α-amylase and promoted glucose uptake in C2C12 cells. Whereas MLB significantly (p < 0.001) up-regulated PI3K and PPARγ transcripts with a corresponding increase in GLUT-4 transcripts within the muscle cells, friedelan-3-one only up-regulated PI3K and GLUT-4 transcripts to promote glucose transport. Friedelan-3-one was shown to be non-carcinogenic, non-hepatotoxic, has decent oral bioavailability and a good compound for optimisation into a drug candidate. The study has demonstrated that MLB possess hypoglycaemic and anti-hyperlipidaemic activities and could be used as a therapeutic agent in the management of diabetes mellitus., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)
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- 2021
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24. Flavanols and triterpenoids from Myrianthus arboreus ameliorate hyperglycaemia in streptozotocin-induced diabetic rats possibly via glucose uptake enhancement and α-amylase inhibition.
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Harley BK, Dickson RA, Amponsah IK, Ben IO, Adongo DW, Fleischer TC, and Habtemariam S
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- Animals, Cell Line, Computer Simulation, Dose-Response Relationship, Drug, Flavonols administration & dosage, Flavonols isolation & purification, Flavonols pharmacology, Glucose, Hyperglycemia drug therapy, Hypoglycemic Agents administration & dosage, Hypoglycemic Agents isolation & purification, Male, Mice, Plant Extracts administration & dosage, Rats, Rats, Sprague-Dawley, Streptozocin, Triterpenes administration & dosage, Triterpenes isolation & purification, Triterpenes pharmacology, Diabetes Mellitus, Experimental drug therapy, Hypoglycemic Agents pharmacology, Plant Extracts pharmacology, Urticaceae chemistry
- Abstract
Myrianthus arboreus is use traditionally as an antidiabetic agent in Ghana. We reported the in vivo antidiabetic activity of its 70 % ethanol stem bark extract (MAB) which we found to be strongly concentrated in its EtOAc fraction using glucose uptake and enzyme inhibitory assays. The present study sought to investigate the in vivo hypoglycaemic and anti-hyperlipidaemic activity of this ethyl acetate fraction of MAB (MAB-EtOAc, 50 and 100 mg/kg) in streptozotocin (STZ)-induced diabetic rats for 21 days, isolate and evaluate the bioactive constituents responsible for the antidiabetic activity. In silico pharmacokinetic and toxicity properties of the most active compound was also determined. MAB-EtOAc significantly (p < 0.001) reduced the blood glucose levels while normalizing considerably the altered serum lipid parameters of the diabetic rats which was comparable to glibenclamide (5 mg/kg). Chemical investigation of MAB-EtOAc led to the isolation of seven known compounds including three flavanols which are reported for the first time in the plant: epicatechin (1), epigallocatechin (2), dulcisflavan (3), euscaphic acid (4), tormentic acid (5), sitosterol-3-O-β-d-glucopyranoside (6) and arjunolic acid (7). The compounds markedly inhibited the action of α-amylase and, except for 4 and 6, which stimulated considerably glucose uptake in C2C12 cells. Compounds 2, 3, 5, 6 and 7 which were further evaluated in STZ-induced diabetic rats demonstrated hypoglycaemic and anti-hyperlipidaemic activities which, however, were not comparable with MAB-EtOAc. Compound 3, the most active compound was predicted to be non-toxic, non-mutagenic, has reasonable oral bioavailability and a decent substrate for further drug development. The findings of this study show that the isolated compounds may contribute to the antidiabetic activity of M. arboreus and could serve as marker compounds for the quality control of herbal medicines that would be made from the plant., (Copyright © 2020. Published by Elsevier Masson SAS.)
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- 2020
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25. Performance of a proteomic preterm delivery predictor in a large independent prospective cohort.
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Markenson GR, Saade GR, Laurent LC, Heyborne KD, Coonrod DV, Schoen CN, Baxter JK, Haas DM, Longo S, Grobman WA, Sullivan SA, Major CA, Wheeler SM, Pereira LM, Su EJ, Boggess KA, Hawk AF, Crockett AH, Fox AC, Polpitiya A, Fleischer TC, Critchfield GC, Burchard J, Boniface JJ, and Lam GK
- Subjects
- Cohort Studies, Female, Gestational Age, Humans, Infant, Newborn, Pregnancy, Prospective Studies, Proteomics, United States, Premature Birth
- Abstract
Background: Preterm birth remains a common and devastating complication of pregnancy. There remains a need for effective and accurate screening methods for preterm birth. Using a proteomic approach, we previously discovered and validated (Proteomic Assessment of Preterm Risk study, NCT01371019) a preterm birth predictor comprising a ratio of insulin-like growth factor-binding protein 4 to sex hormone-binding globulin., Objective: To determine the performance of the ratio of insulin-like growth factor-binding protein 4 to sex hormone-binding globulin to predict both spontaneous and medically indicated very preterm births, in an independent cohort distinct from the one in which it was developed., Study Design: This was a prospective observational study (Multicenter Assessment of a Spontaneous Preterm Birth Risk Predictor, NCT02787213) at 18 sites in the United States. Women had blood drawn at 17
2 ), resulted in an area under the receiver operating characteristic curve of 0.76 (95% confidence interval, 0.59-0.93; P=.023). The ratio of insulin-like growth factor-binding protein 4 to sex hormone-binding globulin ratio predicted neonatal outcomes with respective area under the receiver operating characteristic curve of 0.67 (95% confidence interval, 0.57-0.77; P=.005) and 0.78 (95% confidence interval, 0.63-0.93; P=.026) for neonatal composite morbidity and mortality scores of ≥3 or 4. In addition, the ratio of insulin-like growth factor-binding protein 4 to sex hormone binding globulin significantly stratified neonates with increased length of hospital stay (log rank P=.023)., Conclusion: We confirmed in an independent cohort the ratio of insulin-like growth factor-binding protein 4 to sex hormone-binding globulin ratio as a predictor of very preterm birth, with additional prediction of increased length of neonatal hospital stay and increased severity of adverse neonatal outcomes. Potential uses of the ratio of insulin-like growth factor-binding protein 4 to sex hormone-binding globulin predictor may be to risk stratify patients for implementation of preterm birth preventive strategies and direct patients to appropriate levels of care., (Copyright © 2020 Elsevier Inc. All rights reserved.)0/7 to 216/7 weeks' gestation. For confirmation, we planned to analyze a randomly selected subgroup of women having blood drawn between 191/7 and 206/7 weeks' gestation, with the results of the remaining study participants blinded for future validation studies. Serum from participants was analyzed by mass spectrometry. Neonatal morbidity and mortality were analyzed using a composite score by a method from the PREGNANT trial (NCT00615550, Hassan et al). Scores of 0-3 reflect increasing numbers of morbidities or length of neonatal intensive care unit stay, and 4 represents perinatal mortality., Results: A total of 5011 women were enrolled, with 847 included in this planned substudy analysis. There were 9 preterm birth cases at <320/7 weeks' gestation and 838 noncases at ≥320/7 weeks' gestation; 21 of 847 infants had neonatal composite morbidity and mortality index scores of ≥3, and 4 of 21 had a score of 4. The ratio of insulin-like growth factor-binding protein 4 to sex hormone-binding globulin ratio was substantially higher in both preterm births at <320/7 weeks' gestation and there were more severe neonatal outcomes. The ratio of insulin-like growth factor-binding protein 4 to sex hormone-binding globulin ratio was significantly predictive of birth at <320/7 weeks' gestation (area under the receiver operating characteristic curve, 0.71; 95% confidence interval, 0.55-0.87; P=.016). Stratification by body mass index, optimized in the previous validation study (22- Published
- 2020
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26. Targeted Identification of Protein Interactions in Eukaryotic mRNA Translation.
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Link AJ, Niu X, Weaver CM, Jennings JL, Duncan DT, McAfee KJ, Sammons M, Gerbasi VR, Farley AR, Fleischer TC, Browne CM, Samir P, Galassie A, and Boone B
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- Chromatography, Liquid, Protein Interaction Mapping, Proteomics, Saccharomyces cerevisiae genetics, Saccharomyces cerevisiae Proteins analysis, Saccharomyces cerevisiae Proteins isolation & purification, Tandem Mass Spectrometry, Protein Biosynthesis, Ribosomes metabolism, Saccharomyces cerevisiae metabolism, Saccharomyces cerevisiae Proteins metabolism
- Abstract
To identify protein-protein interactions and phosphorylated amino acid sites in eukaryotic mRNA translation, replicate TAP-MudPIT and control experiments are performed targeting Saccharomyces cerevisiae genes previously implicated in eukaryotic mRNA translation by their genetic and/or functional roles in translation initiation, elongation, termination, or interactions with ribosomal complexes. Replicate tandem affinity purifications of each targeted yeast TAP-tagged mRNA translation protein coupled with multidimensional liquid chromatography and tandem mass spectrometry analysis are used to identify and quantify copurifying proteins. To improve sensitivity and minimize spurious, nonspecific interactions, a novel cross-validation approach is employed to identify the most statistically significant protein-protein interactions. Using experimental and computational strategies discussed herein, the previously described protein composition of the canonical eukaryotic mRNA translation initiation, elongation, and termination complexes is calculated. In addition, statistically significant unpublished protein interactions and phosphorylation sites for S. cerevisiae's mRNA translation proteins and complexes are identified., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
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- 2020
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27. Analytical validation of protein biomarkers for risk of spontaneous preterm birth.
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Bradford C, Severinsen R, Pugmire T, Rasmussen M, Stoddard K, Uemura Y, Wheelwright S, Mentinova M, Chelsky D, Hunsucker SW, Kearney P, Hickok D, Fleischer TC, Ichetovkin I, Boniface JJ, Critchfield GC, and Peltier JM
- Abstract
Presented are the validation results of a second-generation assay for determining the relative abundances of two protein biomarkers found in maternal serum that predict an individual's risk of spontaneous preterm birth. The sample preparation workflow is complex, consisting of immuno-depletion of high-abundance serum proteins, tryptic digestion of the immuno-depleted fraction to generate surrogate peptide analytes, and detection by tandem mass spectrometry. The method was determined to be robust on observation of the following characteristics: classifier peptide detection precision was excellent; results were accurate when compared to a reference method; results were linear over a clinically relevant range; the limits of quantitation encompassed the range of expected results; and the method demonstrated analytical specificity and resilience to differences in patient serum and common endogenous interferents., (© 2017 The Authors. Published by Elsevier B.V. on behalf of The Association for Mass Spectrometry: Applications to the Clinical Lab (MSACL).)
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- 2017
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28. Development and validation of a spontaneous preterm delivery predictor in asymptomatic women.
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Saade GR, Boggess KA, Sullivan SA, Markenson GR, Iams JD, Coonrod DV, Pereira LM, Esplin MS, Cousins LM, Lam GK, Hoffman MK, Severinsen RD, Pugmire T, Flick JS, Fox AC, Lueth AJ, Rust SR, Mazzola E, Hsu C, Dufford MT, Bradford CL, Ichetovkin IE, Fleischer TC, Polpitiya AD, Critchfield GC, Kearney PE, Boniface JJ, and Hickok DE
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- Biomarkers blood, Female, Humans, Mass Spectrometry, Pregnancy, Pregnancy Trimester, Second blood, Prospective Studies, ROC Curve, Sensitivity and Specificity, Insulin-Like Growth Factor Binding Protein 4 blood, Premature Birth blood, Sex Hormone-Binding Globulin analysis
- Abstract
Background: Preterm delivery remains the leading cause of perinatal mortality. Risk factors and biomarkers have traditionally failed to identify the majority of preterm deliveries., Objective: To develop and validate a mass spectrometry-based serum test to predict spontaneous preterm delivery in asymptomatic pregnant women., Study Design: A total of 5501 pregnant women were enrolled between 17(0/7) and 28(6/7) weeks gestational age in the prospective Proteomic Assessment of Preterm Risk study at 11 sites in the United States between 2011 and 2013. Maternal blood was collected at enrollment and outcomes collected following delivery. Maternal serum was processed by a proteomic workflow, and proteins were quantified by multiple reaction monitoring mass spectrometry. The discovery and verification process identified 2 serum proteins, insulin-like growth factor-binding protein 4 (IBP4) and sex hormone-binding globulin (SHBG), as predictors of spontaneous preterm delivery. We evaluated a predictor using the log ratio of the measures of IBP4 and SHBG (IBP4/SHBG) in a clinical validation study to classify spontaneous preterm delivery cases (<37(0/7) weeks gestational age) in a nested case-control cohort different from subjects used in discovery and verification. Strict blinding and independent statistical analyses were employed., Results: The predictor had an area under the receiver operating characteristic curve value of 0.75 and sensitivity and specificity of 0.75 and 0.74, respectively. The IBP4/SHBG predictor at this sensitivity and specificity had an odds ratio of 5.04 for spontaneous preterm delivery. Accuracy of the IBP4/SHBG predictor increased using earlier case-vs-control gestational age cutoffs (eg, <35(0/7) vs ≥35(0/7) weeks gestational age). Importantly, higher-risk subjects defined by the IBP4/SHBG predictor score generally gave birth earlier than lower-risk subjects., Conclusion: A serum-based molecular predictor identifies asymptomatic pregnant women at risk of spontaneous preterm delivery, which may provide utility in identifying women at risk at an early stage of pregnancy to allow for clinical intervention. This early detection would guide enhanced levels of care and accelerate development of clinical strategies to prevent preterm delivery., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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29. Chemical constituents from Gouania longipetala and Glyphaea brevis.
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Ekuadzi E, Dickson RA, Fleischer TC, Amponsah IK, Pistorius D, and Oberer L
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- Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacology, Biflavonoids chemistry, Biflavonoids isolation & purification, Catechin chemistry, Catechin isolation & purification, Free Radical Scavengers chemistry, Free Radical Scavengers pharmacology, Macrolides chemistry, Macrolides isolation & purification, Molecular Structure, Plant Bark chemistry, Proanthocyanidins chemistry, Proanthocyanidins isolation & purification, Anti-Bacterial Agents isolation & purification, Free Radical Scavengers isolation & purification, Plants, Medicinal chemistry, Rhamnaceae chemistry, Tiliaceae chemistry
- Abstract
Five compounds were isolated altogether from the two medicinal plants. Glycerol monotricosanoate (1), palmarumycin BG1 (2) and de-O-methyllasiodiplodin (3) were isolated from Gouania longipetala. In addition, epicatechin (4) and its dimer procyanidin B2 (5) were isolated from the stem bark of Glyphaea brevis. Their structures were elucidated by using spectroscopic experiments. They exhibited radical scavenging and moderate antibacterial effects.
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- 2014
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30. Anti-inflammatory, antioxidant, and selective antibacterial effects of Euadenia eminens root bark.
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Dickson R, Fleischer T, Ekuadzi E, and Komlaga G
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- Animals, Ascorbic Acid metabolism, Carrageenan, Chickens, Edema drug therapy, Free Radical Scavengers pharmacology, Inhibitory Concentration 50, Male, Microbial Sensitivity Tests, Phenols analysis, Phenols pharmacology, Plant Bark, Plant Extracts therapeutic use, Plant Roots, Tannins analysis, Anti-Bacterial Agents pharmacology, Anti-Inflammatory Agents pharmacology, Antioxidants pharmacology, Bacillus drug effects, Capparaceae chemistry, Plant Extracts pharmacology, Tannins pharmacology
- Abstract
Euadenia eminens Hook f. (Capparaceae) has traditional uses in the management of conjunctivitis, iritis, ophthalmia, tuberculosis, otalgia and rectal prolapse. The fruit pulp is also eaten as an aphrodisiac. In this paper, we report on the anti-inflammatory, antioxidant and antibacterial effects of its roots. A 70 % ethanol extract was tested for anti-inflammatory effect using the carrageenan-induced oedema in chicks. Free radical scavenging, total antioxidant and total phenol content were assessed spectrophotometrically. The extract was tested for antibacterial activity using the agar well diffusion method and micro dilution assays. The 70% ethanol extract gave a maximal inhibition of oedema by 74.18 % at 30 mg/kg. The total antioxidant capacity expressed in terms of ascorbic acid was 0.609 mg/g dry weight. The total phenol in terms of tannic acid was 7.25 mg/g dry weight. The extract also demonstrated free radical scavenging activity yielding IC50 value of 1.175 mg/mL. The root extract however, showed selective antibacterial activity, inhibiting growth of two microorganisms; Bacillus subtilis and Bacillus thurigiensis. The MICs were 500 and 1000 µg/mL respectively. These results may account in part for the ethnopharmacological use of the plant.
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- 2011
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31. Analogues of 4-[(7-Bromo-2-methyl-4-oxo-3H-quinazolin-6-yl)methylprop-2-ynylamino]-N-(3-pyridylmethyl)benzamide (CB-30865) as potent inhibitors of nicotinamide phosphoribosyltransferase (Nampt).
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Lockman JW, Murphy BR, Zigar DF, Judd WR, Slattum PM, Gao ZH, Ostanin K, Green J, McKinnon R, Terry-Lorenzo RT, Fleischer TC, Boniface JJ, Shenderovich M, and Willardsen JA
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- Antineoplastic Agents chemistry, Antineoplastic Agents pharmacology, Benzamides chemistry, Benzamides pharmacology, Drug Screening Assays, Antitumor, HCT116 Cells, Humans, Models, Molecular, Quinazolines chemistry, Quinazolines pharmacology, Structure-Activity Relationship, Antineoplastic Agents chemical synthesis, Benzamides chemical synthesis, Nicotinamide Phosphoribosyltransferase antagonists & inhibitors, Quinazolines chemical synthesis
- Abstract
We have shown previously that the target of the potent cytotoxic agent 4-[(7-bromo-2-methyl-4-oxo-3H-quinazolin-6-yl)methyl-prop-2-ynylamino]-N-(3-pyridylmethyl)benzamide (CB38065, 1) is nicotinamide phosphoribosyltransferase (Nampt). With its cellular target known we sought to optimize the biochemical and cellular Nampt activity of 1 as well as its cytotoxicity. It was found that a 3-pyridylmethylamide substituent in the A region was critical to cellular Nampt activity and cytotoxicity, although other aromatic substitution did yield compounds with submicromolar enzymatic inhibition. Small unsaturated groups worked best in the D-region of the molecule, with 3,3-dimethylallyl providing optimal potency. The E region required a quinazolin-4-one or 1,2,3-benzotriazin-4-one group for activity, and many substituents were tolerated at C² of the quinazolin-4-one. The best compounds showed subnanomolar inhibition of Nampt and low nanomolar cytotoxicity in cellular assays.
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- 2010
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32. Chemical proteomics identifies Nampt as the target of CB30865, an orphan cytotoxic compound.
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Fleischer TC, Murphy BR, Flick JS, Terry-Lorenzo RT, Gao ZH, Davis T, McKinnon R, Ostanin K, Willardsen JA, and Boniface JJ
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- Antineoplastic Agents chemistry, Drug Discovery, HCT116 Cells, Humans, Nicotinamide Phosphoribosyltransferase antagonists & inhibitors, Quinazolines chemistry, Antineoplastic Agents metabolism, Antineoplastic Agents pharmacology, Nicotinamide Phosphoribosyltransferase metabolism, Orphan Drug Production, Proteomics methods, Quinazolines metabolism, Quinazolines pharmacology
- Abstract
Drug discovery based on cellular phenotypes is impeded by the challenge of identifying the molecular target. To alleviate this problem, we developed a chemical proteomic process to identify cellular proteins that bind to small molecules. CB30865 is a potent (subnanomolar) and selective cytotoxic compound of previously unknown mechanism of action. By combining chemical proteomics with biochemical and cellular pharmacology we have determined that CB30865 cytotoxicity is due to subnanomolar inhibition of nicotinamide phosphoribosyltransferase (Nampt), an enzyme present in the NAD biosynthetic pathway. Cancer cells develop dependence on Nampt due to increased energy requirements and the elevated activity of NAD consuming enzymes such as sirtuins and mono and poly(ADP-ribose) polymerases (PARPs). These findings suggest new chemical starting points for Nampt inhibitors and further implicate this enzyme as a target in cancer.
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- 2010
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33. Assesssing herbal medical practitioners in professional qualifying examination in Ghana, a model.
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Adusi-Poku Y, Okine LK, Hlortsi-Akakpo FK, Fleischer TC, Mensah ML, Arhin P, Agyemfra G, Dabra T, and Mensah EN
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- Curriculum, Ghana, Health Knowledge, Attitudes, Practice, Herbal Medicine standards, Humans, Medicine, African Traditional, Primary Health Care, Professional Competence, Certification, Herbal Medicine education, Internship and Residency organization & administration
- Abstract
About 70% of Ghanaians depend on Alternative health practice for their primary health care needs. Hence, there is the need to streamline and regulate these practices. Graduates from the Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology (K.N.U.S.T), Kumasi-Ghana were assessed by the Professional Qualifying Examination Board of the Traditional Medicine Practice Council (TMPC), Ghana, after two years of internship training. A model of assessment took into consideration, the scope of the university training, internship and the primary health care needs of the society.
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- 2009
34. In vitro evaluation of effects of two Ghanaian plants relevant to wound healing.
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Mensah AY, Houghton PJ, Dickson RA, Fleischer TC, Heinrich M, and Bremner P
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- Animals, Antioxidants pharmacology, Bacteria drug effects, Brain drug effects, Cattle, Cells, Cultured, Fungi drug effects, Hydrogen Peroxide administration & dosage, Inhibitory Concentration 50, Methanol chemistry, Microbial Sensitivity Tests, Plant Extracts therapeutic use, Bignoniaceae chemistry, Commelina chemistry, Phytotherapy, Plant Extracts pharmacology, Wound Healing drug effects, Wounds and Injuries drug therapy
- Abstract
Commelina diffusa and Spathodea campanulata are used as wound-healing agents in Ashanti traditional medicine in Ghana. The methanol extracts of Commelina diffusa herb and Spathodea campanulata bark showed some level of antimicrobial activity with C. diffusa exhibiting selective antifungal activity against Trichophyton species. The extracts reduced the peroxidation of bovine brain extract with an IC(50) value of 1.39 mg/mL and 0.24 mg/mL, respectively. In addition the extracts also exhibited significant antioxidant activity by protecting MRC-5 cells from hydrogen peroxide induced oxidant injury at concentrations between 1 microg/mL and 10 microg/mL. The extracts showed no inhibition of NF-kappaB at 100 microg/mL. The antioxidant activities and antimicrobial activities suggest that the use of the plants in wound healing may be based on antioxidant and antiseptic effects of its constituents., (Copyright (c) 2006 John Wiley & Sons, Ltd.)
- Published
- 2006
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35. Systematic identification and functional screens of uncharacterized proteins associated with eukaryotic ribosomal complexes.
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Fleischer TC, Weaver CM, McAfee KJ, Jennings JL, and Link AJ
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- Amino Acid Sequence, Cell Cycle Proteins genetics, Cell Cycle Proteins metabolism, Gene Deletion, Mass Spectrometry, Molecular Sequence Data, Oncogene Proteins genetics, Oncogene Proteins metabolism, Open Reading Frames, Ribosomal Proteins genetics, Ribosomal Proteins metabolism, Saccharomyces cerevisiae genetics, Saccharomyces cerevisiae Proteins genetics, Saccharomyces cerevisiae Proteins metabolism, Proteomics, Ribosomal Proteins analysis, Ribosomes chemistry, Saccharomyces cerevisiae metabolism, Saccharomyces cerevisiae Proteins analysis
- Abstract
Translation regulation is a critical means by which cells control growth, division, and apoptosis. To gain further insight into translation and related processes, we performed multifaceted mass spectrometry-based proteomic screens of yeast ribosomal complexes and discovered an association of 77 uncharacterized yeast proteins with ribosomes. Immunoblotting revealed an EDTA-dependent cosedimentation with ribosomes in sucrose gradients for 11 candidate translation-machinery-associated (TMA) proteins. Tandem affinity purification linked one candidate, LSM12, to the RNA processing proteins PBP1 and PBP4. A second candidate, TMA46, interacted with RBG1, a GTPase that interacts with ribosomes. By adapting translation assays to high-throughput screening methods, we showed that null yeast strains harboring deletions for several of the TMA genes had alterations in protein synthesis rates (TMA7 and TMA19), susceptibility to drugs that inhibit translation (TMA7), translation fidelity (TMA20), and polyribosome profiles (TMA7, TMA19, and TMA20). TMA20 has significant sequence homology with the oncogene MCT-1. Expression of human MCT-1 in the Deltatma20 yeast mutant complemented translation-related defects, strongly implying that MCT-1 functions in translation-related processes. Together these findings implicate the TMA proteins and, potentially, their human homologs, in translation related processes.
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- 2006
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36. Purifying protein complexes for mass spectrometry: applications to protein translation.
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Link AJ, Fleischer TC, Weaver CM, Gerbasi VR, and Jennings JL
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- Cell Differentiation, Centrifugation, Density Gradient methods, Electrophoresis, Polyacrylamide Gel, Epitopes chemistry, Hydrogen-Ion Concentration, Immunoprecipitation, Models, Biological, RNA, Messenger metabolism, Ribosomes chemistry, Saccharomyces cerevisiae metabolism, Sensitivity and Specificity, Sucrose pharmacology, Temperature, Time Factors, Mass Spectrometry methods, Protein Biosynthesis, Proteins chemistry, Proteins isolation & purification, Proteomics methods
- Abstract
Proteins control and mediate most of the biological activities in the cell. In most cases, proteins either interact with regulatory proteins or function in large molecular assemblies to carryout biological processes. Understanding the functions of individual proteins requires the identification of these interacting proteins. With its speed and sensitivity, mass spectrometry has become the dominant method for identifying components of protein complexes. This article reviews and discusses various approaches to purify protein complexes and analyze the proteins using mass spectrometry. As examples, methods to isolate and analyze protein complexes responsible for the translation of messenger RNAs into polypeptides are described.
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- 2005
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37. Composition and antioxidant activity of the essential oils of Xylopia aethiopica (Dun) A. Rich. (Annonaceae) leaves, stem bark, root bark, and fresh and dried fruits, growing in Ghana.
- Author
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Karioti A, Hadjipavlou-Litina D, Mensah ML, Fleischer TC, and Skaltsa H
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- Food Preservation, Fruit chemistry, Ghana, Monoterpenes analysis, Plant Bark chemistry, Plant Leaves chemistry, Plant Roots chemistry, Plant Stems chemistry, Annonaceae chemistry, Antioxidants analysis, Oils, Volatile chemistry
- Abstract
The chemical composition of the essential oils obtained from the leaves, the barks of the stem and the root, as well as from the fresh and dried fruits of Xylopia aethiopica, growing in Ghana, was investigated by gas chromatography/mass spectrometry analyses. Kovats indices, mass spectra, and standard compounds were used to identify a total of 93 individual compounds. The monoterpene hydrocarbons formed the main portion in all studied samples. beta-Pinene was predominant in all cases, while trans-m-mentha-1(7),8-diene was the main compound in the essential oils of the leaves and the barks of roots and stems. Their potential antioxidant activity was also investigated and found to be significant in scavenging superoxide anion radical.
- Published
- 2004
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38. Evaluation of the antioxidant and free radical scavenging properties of Secamone afzelii Rhoem.
- Author
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Mensah AY, Houghton PJ, Akyirem GN, Fleischer TC, Mensah ML, Sarpong K, and Adosraku R
- Subjects
- Antioxidants chemistry, Biphenyl Compounds, Chromatography, High Pressure Liquid, Free Radical Scavengers chemistry, Humans, Inhibitory Concentration 50, Lipid Peroxidation drug effects, Liposomes metabolism, Picrates chemistry, Plant Extracts chemistry, Plant Stems, Antioxidants pharmacology, Apocynaceae, Free Radical Scavengers pharmacology, Phytotherapy, Plant Extracts pharmacology
- Abstract
The antioxidant activity of a methanol extract of Secamone afzelii stems was tested using the DPPH assay and the active compound was identified as alpha-tocopherol. HPLC determination showed that 0.12% w/w alpha-tocopherol was present in the plant. The total extract also showed effective free radical scavenging activity in the assay for non-enzymatic lipid peroxidation in liposomes with an IC50 value of 90 microg/mL, with alpha-tocopherol isolated from the plant having an IC50 of 15 microg/mL in the same system, thus demonstrating the presence of other antioxidants., (2004 John Wiley & Sons, Ltd.)
- Published
- 2004
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39. Identification of a Drosophila Myb-E2F2/RBF transcriptional repressor complex.
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Lewis PW, Beall EL, Fleischer TC, Georlette D, Link AJ, and Botchan MR
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- Animals, Chromatography, Gel, Drosophila, E2F2 Transcription Factor, Immunoprecipitation, Retinoblastoma Protein, Drosophila Proteins metabolism, Proto-Oncogene Proteins c-myb metabolism, Repressor Proteins metabolism, Transcription Factors metabolism
- Abstract
The Drosophila Myb complex has roles in both activating and repressing developmentally regulated DNA replication. To further understand biochemically the functions of the Myb complex, we fractionated Drosophila embryo extracts relying upon affinity chromatography. We found that E2F2, DP, RBF1, RBF2, and the Drosophila homolog of LIN-52, a class B synthetic multivulva (synMuv) protein, copurify with the Myb complex components to form the Myb-MuvB complex. In addition, we found that the transcriptional repressor protein, lethal (3) malignant brain tumor protein, L(3)MBT, and the histone deacetylase, Rpd3, associated with the Myb-MuvB complex. Members of the Myb-MuvB complex were localized to promoters and were shown to corepress transcription of developmentally regulated genes. These and other data now link together the Myb and E2F2 complexes in higher-order assembly to specific chromosomal sites for the regulation of transcription.
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- 2004
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40. Identification and characterization of three new components of the mSin3A corepressor complex.
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Fleischer TC, Yun UJ, and Ayer DE
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- Blotting, Northern, Blotting, Western, Cell Line, Chromatography, Gel, DNA metabolism, DNA, Complementary metabolism, Electrophoresis, Polyacrylamide Gel, Gene Deletion, Histone Deacetylase 1, Histone Deacetylase 2, Histone Deacetylases metabolism, Humans, K562 Cells, Precipitin Tests, Protein Binding, Protein Structure, Tertiary, Recombinant Fusion Proteins metabolism, Repressor Proteins metabolism, Saccharomyces cerevisiae metabolism, Sin3 Histone Deacetylase and Corepressor Complex, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Transcription Factors metabolism, Transfection, Tumor Cells, Cultured, Repressor Proteins chemistry, Transcription Factors chemistry
- Abstract
The mSin3A corepressor complex contains 7 to 10 tightly associated polypeptides and is utilized by many transcriptional repressors. Much of the corepressor function of mSin3A derives from associations with the histone deacetylases HDAC1 and HDAC2; however, the contributions of the other mSin3A-associated polypeptides remain largely unknown. We have purified an mSin3A complex from K562 erythroleukemia cells and identified three new mSin3A-associated proteins (SAP): SAP180, SAP130, and SAP45. SAP180 is 40% identical to a previously identified mSin3A-associated protein, RBP1. SAP45 is identical to mSDS3, the human ortholog of the SDS3p component of the Saccharomyces cerevisiae Sin3p-Rpd3p corepressor complex. SAP130 does not have detectable homology to other proteins. Coimmunoprecipitation and gel filtration data suggest that the new SAPs are, at the very least, components of the same mSin3A complex. Each new SAP repressed transcription when tethered to DNA. Furthermore, repression correlated with mSin3A binding, suggesting that the new SAPs are components of functional mSin3A corepressor complexes. SAP180 has two repression domains: a C-terminal domain, which interacts with the mSin3A-HDAC complex, and an N-terminal domain, which functions independently of mSin3A-HDAC. SAP130 has a repression domain at its C terminus that interacts with the mSin3A-HDAC complex and an N-terminal domain that probably mediates an interaction with a transcriptional activator. Together, our data suggest that these novel SAPs function in the assembly and/or enzymatic activity of the mSin3A complex or in mediating interactions between the mSin3A complex and other regulatory complexes. Finally, all three SAPs bind to the HDAC-interaction domain (HID) of mSin3A, suggesting that the HID functions as the assembly interface for the mSin3A corepressor complex.
- Published
- 2003
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41. Antimicrobial activity of the leaves and seeds of Bixa orellana.
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Fleischer TC, Ameade EP, Mensah ML, and Sawer IK
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- Anti-Infective Agents administration & dosage, Anti-Infective Agents therapeutic use, Candida albicans drug effects, Humans, Microbial Sensitivity Tests, Plant Extracts administration & dosage, Plant Extracts therapeutic use, Plant Leaves, Seeds, Anti-Infective Agents pharmacology, Bixaceae, Gram-Negative Bacteria drug effects, Gram-Positive Bacteria drug effects, Phytotherapy, Plant Extracts pharmacology
- Abstract
The ethanolic extracts of the leaves and seeds of Bixa orellana showed a broad spectrum of antimicrobial activity. The activity of the leaf extract was more pronounced.
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- 2003
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42. Antimicrobial activity of the leaves and flowering tops of Acanthospermum hispidum.
- Author
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Fleischer TC, Ameade EP, and Sawer IK
- Subjects
- Anti-Infective Agents administration & dosage, Anti-Infective Agents therapeutic use, Flowering Tops, Humans, Microbial Sensitivity Tests, Plant Extracts administration & dosage, Plant Extracts therapeutic use, Plant Leaves, Anti-Infective Agents pharmacology, Asteraceae, Gram-Negative Bacteria drug effects, Gram-Positive Bacteria drug effects, Phytotherapy, Plant Extracts pharmacology
- Abstract
The ethanolic extracts of the leaves and flowering tops of Acanthospermum hispidum showed varying degrees of activity against a wide range of pathogenic bacteria. The activity resided mostly in the polar fractions of the alcoholic extract, being only slight in the non-polar fractions. No activity was observed for the aqueous extract of the fresh plant material.
- Published
- 2003
- Full Text
- View/download PDF
43. A role for histone deacetylase activity in HDAC1-mediated transcriptional repression.
- Author
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Hassig CA, Tong JK, Fleischer TC, Owa T, Grable PG, Ayer DE, and Schreiber SL
- Subjects
- Amino Acid Sequence, Antibodies pharmacology, Binding Sites genetics, Gene Expression Regulation, Enzymologic drug effects, HeLa Cells, Histone Deacetylase 1, Histone Deacetylase Inhibitors, Histone Deacetylases immunology, Histones genetics, Humans, Molecular Sequence Data, Mutagenesis, Site-Directed, Substrate Specificity genetics, Anti-Bacterial Agents pharmacology, Enzyme Inhibitors pharmacology, Histone Deacetylases genetics, Histone Deacetylases metabolism, Histones metabolism, Peptides, Transcriptional Activation drug effects
- Abstract
Treatment of mammalian cells with small molecule histone deacetylase (HDAC) inhibitors induces changes in the transcription of specific genes. These changes correlate directly with an increase in the acetylation levels of all four core histones in vivo. Antibodies directed against endogenous HDAC1, HDAC2, or HDAC3 immunoprecipitate histone deacetylase activity that is inhibited in vitro by the small molecule trapoxin (TPX), and all three HDACs are retained by a TPX-affinity matrix. HDAC1 and HDAC2 are associated in HeLa cells in a complex that is predominantly separate from an HDAC3 immune complex. Both Jurkat HDAC1 and HeLa HDAC1/2 immune complexes deacetylate all four core histones and recombinant HDAC1 deacetylates free and nucleosomal histones in vitro. Purified recombinant HDAC1 deacetylates core histones in the absence of protein cofactors. Site-directed mutagenesis was used to identify residues required for the enzymatic and structural integrity of HDAC1. Mutation of any one of four conserved residues causes deleterious effects on deacetylase activity and a reduced ability to bind a TPX-affinity matrix. A subset of these mutations also cause a decreased interaction with the HDAC1-associated proteins RbAp48 and mSin3A. Disruption of histone deacetylase activity either by TPX or by direct mutation of a histidine presumed to be in the active site abrogates HDAC1-mediated transcriptional repression of a targeted reporter gene in vivo.
- Published
- 1998
- Full Text
- View/download PDF
44. Histone deacetylase activity is required for full transcriptional repression by mSin3A.
- Author
-
Hassig CA, Fleischer TC, Billin AN, Schreiber SL, and Ayer DE
- Subjects
- Acetylation, Animals, Anti-Bacterial Agents pharmacology, Carrier Proteins genetics, Carrier Proteins metabolism, Cells, Cultured enzymology, DNA-Binding Proteins metabolism, Enzyme Inhibitors pharmacology, Gene Expression Regulation, Enzymologic physiology, Histone Deacetylase Inhibitors, Multienzyme Complexes genetics, Multienzyme Complexes metabolism, Nuclear Proteins genetics, Nuclear Proteins metabolism, Rabbits, Retinoblastoma, Sin3 Histone Deacetylase and Corepressor Complex, Transcription Factors genetics, Transcription Factors metabolism, Transcription, Genetic drug effects, DNA-Binding Proteins genetics, Histone Deacetylases genetics, Histone Deacetylases metabolism, Peptides, Repressor Proteins genetics, Repressor Proteins metabolism, Transcription, Genetic physiology
- Abstract
Members of the Mad family of bHLH-Zip proteins heterodimerize with Max to repress transcription in a sequence-specific manner. Transcriptional repression by Mad:Max heterodimers is mediated by ternary complex formation with either of the corepressors mSin3A or mSin3B. We report here that mSin3A is an in vivo component of large, heterogeneous multiprotein complexes and is tightly and specifically associated with at least seven polypeptides. Two of the mSin3A-associated proteins, p50 and p55, are highly related to the histone deacetylase HDAC1. The mSin3A immunocomplexes possess histone deacetylase activity that is sensitive to the specific deacetylase inhibitor trapoxin. mSin3A-targeted repression of a reporter gene is reduced by trapoxin treatment, suggesting that histone deacetylation mediates transcriptional repression through Mad-Max-mSin3A multimeric complexes.
- Published
- 1997
- Full Text
- View/download PDF
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