Lead (Pb(2+)) exposure continues to be a significant public health problem. Therefore, it is vital to have a continuous epidemiological dataset for a better understanding of Pb(2+) toxicity. In the present study, we have exposed stem cells isolated from deciduous and permanent teeth, periodontal ligament, and bone marrow to five different types of Pb(2+) concentrations (160, 80, 40, 20, and 10 µM) for 24 hours to identify the adverse effects of Pb(2+) on the proliferation, differentiation, and gene expression on these cell lines. We found that Pb(2+) treatment altered the morphology and adhesion of the cells in a dose-dependent manner. There were no significant changes in terms of cell surface phenotypes. Cells exposed to Pb(2+) continued to differentiate into chondrogenesis and adipogenesis, and a severe downregulation was observed in osteogenesis. Gene expression studies revealed a constant expression of key markers associated with stemness (Oct 4, Rex 1) and DNA repair enzyme markers, but downregulation occurred with some ectoderm and endoderm markers, demonstrating an irregular and untimely differentiation trail. Our study revealed for the first time that Pb(2+) exposure not only affects the phenotypic characteristics but also induces significant alteration in the differentiation and gene expression in the cells.
Matched MeSH terms: Dose-Response Relationship, Drug
Arachidonic acid and its metabolites have generated a heightened interest due to their significant role in inflammation. Inhibiting the enzymes involved in arachidonic acid metabolism has been considered as the synergistic anti-inflammatory effect. A series of novel curcumin diarylpentanoid analogues were synthesized and evaluated for their inhibitory effects on activity of secretory phospholipase A2 , cyclooxygenases, soybean lipo-oxygenase as well as microsomal prostaglandin E synthase-1. Among the curcumin analogues, compounds 3, 6, 9, 12, and 17 exhibited strong inhibition of secretory phospholipase A2 activity, with IC50 values ranging from 5.89 to 11.02 μm. Seven curcumin analogues 1, 3, 6, 7, 9, 11, and 12 showed inhibition of cyclooxygenases-2 with IC50 values in the range of 46.11 to 94.86 μm, which were lower than that of curcumin. Compounds 3, 6, 7, 12, and 17 showed strong inhibition of lipo-oxygenase enzyme activity. Preliminary screening of diarylpentanoid curcumin analogues for microsomal prostaglandin E synthase-1 activity revealed that four diarylpentanoid curcumin analogues 5, 6, 7, and 13 demonstrated higher inhibition of microsomal prostaglandin E synthase-1 activity with IC50 ranging from 2.41 to 4.48 μm, which was less than that of curcumin. The present results suggest that some of these diarylpentanoid analogues were able to inhibit the activity of these enzymes. This raises the possibility that diarylpentanoid analogues of curcumin might serve as useful starting point for the design of improved anti-inflammatory agents.
Matched MeSH terms: Dose-Response Relationship, Drug
Cyclodextrin-ionic liquid polymer (βCD-BIMOTs-TDI) was firstly synthesized using functionalized β-Cyclodextrin (CD) with 1-benzylimidazole (BIM) to form monofunctionalized CD (βCD-BIMOTs) and was further polymerized using toluene diisocyanate (TDI) linker to form insoluble βCD-BIMOTs-TDI. SEM characterization result shows that βCD-BIMOTs-TDI exhibits macropore size while the BET result shows low surface area (1.254 m(2)g(-1)). The unique properties of the ILs allow us to produce materials with different morphologies. The adsorption isotherm and kinetics of 2,4-dichlorophenol (2,4-DCP) onto βCD-BIMOTs-TDI is studied. Freundlich isotherm and pseudo-second order kinetics are found to be the best to represent the data for 2,4-DCP adsorption on the βCD-BIMOTs-TDI. The presence of macropores decreases the mass transfer resistance and increases the adsorption process by reducing the diffusion distance. The change in entropy (ΔS°) and heat of adsorption (ΔH°) for 2,4-DCP on βCD-BIMOTs-TDI were estimated as -55.99 J/Kmol and -18.10 J/mol, respectively. The negative value of Gibbs free energy (ΔG°) indicates that the adsorption process is thermodynamically feasible, spontaneous and chemically controlled. Finally, the interactions between the cavity of βCD-BIMOTs and 2,4-DCP are investigated and the results shows that the inclusion of the complex formation and π-π interaction are the main processes involved in the adsorption process.
Matched MeSH terms: Dose-Response Relationship, Drug
Novel thiazolopyrimidine derivatives have been synthesized via microwave assisted, domino cascade methodology in ionic liquid and evaluated in vitro for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities. Among the newly synthesized compounds 6d, 6a, 6e and 6b displayed higher AChE inhibitory activity than standard drug, galanthamine, with IC50 values of 0.53, 1.47, 1.62 and 2.05μM, respectively. Interestingly, all the compounds except for 6m-r and 6x displayed higher BChE inhibitory potentials than galanthamine with IC50 values ranging from 1.09 to 18.56μM. Molecular docking simulations for 6d possessing the most potent AChE and BChE inhibitory activities, disclosed its binding interactions at the active site gorge of AChE and BChE enzymes.
Matched MeSH terms: Dose-Response Relationship, Drug
Benign Prostatic Hyperplasia (BPH) patients are at risk of acquiring drug-related problems (DRPs), as it is present in the majority of aging men. To date, DRPs among BPH patients have not been well studied. We conducted this retrospective study in a tertiary hospital in Malaysia from January 2009 to June 2012 with the aim of identifying the factors associated with DRPs among BPH patients. The Pharmaceutical Care Network Europe Classification Version (PCNE) 5.01 was used as a tool to classify DRPs. We enrolled 203 patients from 259 hospital admissions. A total of 390 DRPs were found and there was an average of 1.5±1.3 problems per hospitalization. 76.1% of hospital admissions included at least one DRP. The most common DRP categories encountered were drug choice problems (45.9%), drug interactions (24.9%), and dosing problems (13.3%). Factors such as advanced age (p = 0.005), a hospital stay of more than 6 days (p = 0.001), polydrug treatments (p<0.001), multiple comorbidities (p<0.001), and comorbid cardiovascular disease (p = 0.011), diabetes mellitus(p = 0.001), hypertension (p<0.001) and renal impairment (p = 0.011) were significantly associated with the occurrence of DRPs. These data indicated that the prevalence of DRPs is high among BPH patients. The identification of different subtypes of DRPs and the factors associated with DRPs may facilitate risk reduction for BPH patients.
Matched MeSH terms: Dose-Response Relationship, Drug
Anti-osteoporotic drugs are available for treatment of osteoporosis and for preventing osteoporosis complications especially fractures. Most of the current anti-osteoporotic drugs are administered orally or parenterally to target the osteoporosis-affected bones. However, bone is a peripheral organ with limited blood supply. Therefore, the drugs delivered are exposed to various physicochemical and biological factors which affect the bioavailability of the drugs. In preclinical research, the dose of a potential anti-osteoporotic agent used in animal model may be too high for human application when administered via the conventional route of administration. The current anti-osteoporotic drugs need to be administered at higher doses to account for pharmacological interactions. However, this will expose the patients to adverse effects such as the cancer risks of postmenopausal women who took estrogen replacement therapy. There is also problem with patient compliance as anti-osteoporotic drugs may have to be taken for prolonged duration. The current deliveries of drugs need to be improved to overcome these problems. This review discussed several potential drug delivery systems which are able to contain the anti-osteoporosis drugs and release them slowly to the targeted bone. Among them are various carriers, polymers and microsponges, which may not only increase drug efficacy but also reduce adverse effects. The delivery systems allow the drugs to be administered locally at the targeted bone for longer duration, therefore reducing drug frequency and improving patient's compliance. It is hoped that these delivery systems may be applicable for the treatment of osteoporosis in the future to keep tab of the rising osteoporotic fracture incidence.
Matched MeSH terms: Dose-Response Relationship, Drug
Chronic intestinal pseudo-obstruction (CIPO) is a rare clinical syndrome of ineffective intestinal motility characterised by clinical and radiological evidence of intestinal obstruction with no identifiable mechanical lesion. CIPO can either be idiopathic or secondary to a systemic disease, like systemic lupus erythematosus (SLE). Fewer than 30 cases of CIPO secondary to SLE have been reported so far. Here we describe a case of SLE with the initial presentation of CIPO. In SLE-related CIPO, treatment includes a combination of high-dose intravenous corticosteroids, immunosuppressants and supportive care. With awareness of this condition, unnecessary surgical intervention and repeated invasive procedures could be avoided. Early initiation of treatment would avoid complications and bring about resolution of symptoms.
Matched MeSH terms: Dose-Response Relationship, Drug
The effectiveness of influenza vaccination in preventing illness is lower in the elderly; this is why the ability of Lactobacillus plantarum CECT 7315/7316 to stimulate the response to influenza vaccination in elderly was evaluated.
Matched MeSH terms: Dose-Response Relationship, Drug
Acanthaster planci, the crown-of-thorns starfish, naturally endowed with the numerous toxic spines around the dorsal area of its body. Scientific investigations demonstrated several toxico-pharmacological efficacies of A. planci such as, myonecrotic activity, hemorrhagic activity, hemolytic activity, mouse lethality, phospholipase A2 (PLA2) activity, capillary permeability-increasing activity, edema-forming activity, anticoagulant activity and histamine-releasing activity from mast cells. The present study was performed to evaluate the cytotoxic activity of A. planci extracts obtained by different methods of extraction on MCF-7 and HCT-116, human breast and colon cancer cell lines, respectively. Results of the cell proliferation assay showed that PBS extract exhibited very potent cytotoxic activity against both MCF-7 and HCT-116 cell lines with IC(50) of 13.48 μg/mL and 28.78 μg/mL, respectively, while the extracts prepared by Bligh and Dyer method showed moderate cytotoxicity effect against MCF-7 and HCT-116 cell lines, for chloroform extract, IC(50) = 121.37 μg/mL (MCF-7) and 77.65 μg/mL (HCT-116), and for methanol extract, IC(50) = 46.11 μg/mL (MCF-7) and 59.29 μg/mL (HCT-116). However, the extracts prepared by sequential extraction procedure from dried starfish found to be ineffective. This study paves the way for further investigation on the peptide composition in the PBS extract of the starfish to discover potential chemotherapeutic agents.
Matched MeSH terms: Dose-Response Relationship, Drug
The possible cytotoxic effects of vancomycin and its complex with beta-cyclodextrin (β-CD) on human glial cell line (CRL 8621) were studied accordingly by means of MTS assay. The cultured cells were incubated with various concentrations of vancomycin, β-CD as well as β-CD/vancomycin complex ranging from 4.69 to 300 ug/ml. A linear dose-dependency cytotoxicity followed by hermetic-like biphasic dose-dependence was observed after incubation period of 72 hours. In general, significant increase (p<0.001) of cell proliferation was observed at lower concentrations: <18.75 μg/ml for cells treated with β-CD and their complex while < 9.38 μg/ml for cells treated with vancomycin. In contrary, regardless of the treatments given, significant (p<0.001) reduce in cell survival was found at higher concentrations >150 μg/ml. In particular, 50 % inhibitory in vitro was achieved at the concentrations of 115.95 μg/ml (for β-CD), 116.48 μg/ml (for vancomycin) and 115.44 μg/ml (for β-CD/vancomycin complex).
Matched MeSH terms: Dose-Response Relationship, Drug
A new dienamide, (2E,4E)-7-(3',4'-dimethoxyphenyl)-N-ethyl-6-(R)-hydroxyhepta- 2,4-dienamide, named (-)-kunstleramide (1), were isolated from the bark of Beilschmiedia kunstleri Gamble together with one neolignan: (+)-kunstlerone (2) and seven known alkaloids: (+)-nornuciferine (3), (-)-isocaryachine (4), (+)-cassythicine (5), (+)-laurotetanine (6), (+)-boldine (7), noratherosperminine (8), (+)-N-demethylphyllocaryptine (9). Their structures were established from spectroscopic techniques, most notably 1D- and 2D-NMR, UV, IR, OR, circular dichroism (CD) spectra and LCMS-IT-TOF. (-)-Kunstleramide (1) exhibited very poor dose-dependent inhibition of DPPH activity, with an IC₅₀ value of 179.5 ± 4.4 μg/mL, but showed a moderate cytotoxic effect on MTT assays of A375, A549, HT-29, PC-3 and WRL-68 with EC₅₀ values of 64.65, 44.74, 55.94, 73.87 and 70.95 µg/mL, respectively.
Matched MeSH terms: Dose-Response Relationship, Drug
This study examined the prescribing patterns of several first- (FGAs) and second-generation antipsychotic (SGAs) medications administered to older Asian patients with schizophrenia during the period between 2001 and 2009.
Matched MeSH terms: Dose-Response Relationship, Drug
We investigated the association between cigarette smoking and the risk of developing rheumatoid arthritis (RA) in the Malaysian population. A total of 1,056 RA patients and 1,416 matched controls aged 18-70 years within a defined area of Peninsular Malaysia were evaluated in a case-control study between August 2005 and December 2009. A case was defined as a person with early diagnosed RA using the 1987 American College of Rheumatology criteria for RA. Controls were randomly selected matched for sex, age, and residential area. Cases and controls answered a questionnaire on a broad range of issues, including lifestyle factors and smoking habits wherein current and former smoking was classified as ever-smoking. The presence of anti-citrullinated peptide antibodies (ACPA) was determined for cases and controls. We found that ever-smokers had an increased risk of developing ACPA-positive RA [odds ratio (OR) = 4.1, 95% confidence interval (CI) 1.9-9.2] but not ACPA-negative RA (OR = 0.7, 95% CI 0.3-2.0), compared with never-smokers. A significant dose-response relationship between cumulative dose of smoking and risk of ACPA-positive RA was observed (<20 pack-years OR = 3.3, 95% CI 1.1-9.8; at least 20 pack-years OR = 5.2, 95% CI 1.6-17.6). Hence, smoking is associated with an increased risk of ACPA-positive RA in the Malaysian population, in which the genetic context is similar to several other Asian countries.
Matched MeSH terms: Dose-Response Relationship, Drug
Current chemotherapeutic drugs kill cancer cells mainly by inducing apoptosis. However, they become ineffective once cancer cell has the ability to metastasize, hence the poor prognosis and high mortality rate. Therefore, the purpose of this study was to evaluate the antimetastatic potential of Phyllanthus (P. niruri, P. urinaria, P. watsonii, and P. amarus) on lung and breast carcinoma cells.
Matched MeSH terms: Dose-Response Relationship, Drug
Three new limonoids, chisomicines A-C (1-3), have been isolated from the bark of Chisocheton ceramicus. Their structures were determined by 2D NMR, CD spectroscopic methods, and X-ray analysis. Chisomicine A (1) exhibited NO production inhibitory activity in J774.1 cells stimulated by LPS dose-dependently at high cell viability.
Matched MeSH terms: Dose-Response Relationship, Drug
Cytotoxicity, the possible selective activity upon HL60 as well as the anti-proliferation effect of local health supplement wheatgrass and mixture of fibers were investigated in vitro using various cancerous cell line and normal blood cell culture. The IC(50) of wheatgrass-treated HL60 (17.5 ± 1.1, 12.5 ± 0.3, and 16 ± 0.5 microgram/ml for 24, 48 and 72 h, respectively) and fibers-treated HL60 (86.0 ± 5.5, 35.0 ± 2.5, and 52.5 ± 4.5 microgram/ml for 24, 48 and 72 h, respectively) showed that both extracts possessed optimum effect after 48 hours of treatment. No significant cytotoxic effect was observed on other type of cells. For trypan blue dye exclusion method, wheatgrass reduced the number of viable cells by 13.5% (±1.5), 47.1% (±3.6), and 64.9% (±2.7) after 24, 48 and 72 h exposure, respectively. Mixture of fibers reduced the number of viable cells by 36.4% (±2.3), 57.1% (±3.1), and 89.0% (±3.4) after 24, 48 and 72 h exposure, respectively, indicated that necrosis is also an alternative to the apoptotic mechanism of cell death. Annexin-V/propidium iodide staining revealed that both extracts induced apoptosis where early apoptosis had been detected concurrently with the reduction of percentage of cell viability. Cell cycle analysis revealed that in HL60, the percentage of apoptosis increased with time (wheatgrass: 16.0% ± 2.4, 45.3% ± 3.4 and 39.6% ± 4.1; mixture of fibers: 14.6% ± 1.8, 45.4% ± 2.3 and 45.9% ± 1.2) after exposure for 24, 48 and 72 h, respectively at the concentration of 100 microgram/ml and showed optimum effect at 48 hours. Thus, these health products can be a potential alternative supplement for leukaemia patients.
Matched MeSH terms: Dose-Response Relationship, Drug
This study investigated the dose-dependent and time-course effects of intramuscular (i.m.) and intraperitoneal (i.p.) injection of benzo[a]pyrene (BaP) on the biomarkers EROD activity, GST activity, concentrations of BaP metabolites in bile, and visceral fat deposits (Lipid Somatic Index, LSI) in African catfish (Clarias gariepinus). Intraperitoneal injection resulted in 4.5 times higher accumulation of total selected biliary FACs than i.m. injection. Hepatic GST activities were inhibited by BaP via both injection methods. Dose-response relationships between BaP injection and both biliary FAC concentrations and hepatic GST activities were linear in the i.p. injected group but nonlinear in the i.m. injected fish. Hepatic EROD activity and LSI were not significantly affected by BaP exposure by either injection route. We conclude that i.p. is a more effective route of exposure than i.m. for future ecotoxicological studies of PAH exposure in C. gariepinus.
Matched MeSH terms: Dose-Response Relationship, Drug
The present study examines the relationship between the dose of acetaminophen reported to have been ingested by patients and the occurrence of serum acetaminophen levels above the 'possible toxicity' line in patients presenting at the hospital after acetaminophen overdose. The prognostic value of patient-reported dosage cut-offs of 8, 10 and 12 g was determined.
Matched MeSH terms: Dose-Response Relationship, Drug