Displaying publications 501 - 520 of 944 in total

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  1. Hassan MN, Fauzi HM, Husin A, Mustaffa R, Hassan R, Ibrahim MI, et al.
    Oman Med J, 2019 Jan;34(1):34-43.
    PMID: 30671182 DOI: 10.5001/omj.2019.06
    Objectives: Autologous peripheral blood stem cells transplantation (APBSCT) is a therapeutic option which can be used in various hematological, neoplastic disorders including lymphoproliferative disease (LPD). Differences in patient populations and treatment modalities in different transplant centers mean it is important to improve the knowledge of the different factors affecting engraftment after APBSCT for the success of this procedure. We sought to determine the factors influencing neutrophil and platelet engraftment after APBSCT in patients with LPD.

    Methods: We conducted a retrospective review of 70 patients with LPD (35 with lymphoma and 35 with multiple myeloma) who had undergone APBSCT between January 2008 and December 2016. Data obtained included disease type, treatment, and stem cell characteristics. Kaplan-Meier analysis was performed for probabilities of neutrophil and platelet engraftment occurred and was compared by the log-rank test. The multivariate Cox proportional hazards regression model was used for the analysis of potential independent factors influencing engraftment. A p-value < 0.050 was considered statistically significant.

    Results: Most patients were ethnic Malay, the median age at transplantation was 49.5 years. Neutrophil and platelet engraftment occurred in a median time of 18 (range 4-65) and 17 (range 6-66) days, respectively. The majority of patients showed engraftment with 65 (92.9%) and 63 (90.0%) showing neutrophil and platelet engraftment, respectively. We observed significant differences between neutrophil engraftment and patient's weight (< 60/≥ 60 kg), stage of disease at diagnosis, number of previous chemotherapy cycles (< 8/≥ 8), and pre-transplant radiotherapy. While for platelet engraftment, we found significant differences with gender, patient's weight (< 60/≥ 60 kg), pre-transplant radiotherapy, and CD34+ dosage (< 5.0/≥ 5.0 × 106/kg and < 7.0/≥ 7.0 × 106/kg). The stage of disease at diagnosis (p = 0.012) and pre-transplant radiotherapy (p = 0.025) were found to be independent factors for neutrophil engraftment whereas patient's weight (< 60/≥ 60 kg, p = 0.017), age at transplantation (< 50/≥ 50 years, p = 0.038), and CD34+ dosage (< 7.0/≥ 7.0 × 106/kg, p = 0.002) were found to be independent factors for platelet engraftment.

    Conclusions: Patients with LPD who presented at an early stage and with no history of radiotherapy had faster neutrophil engraftment after APBSCT, while a younger age at transplantation with a higher dose of CD34+ cells may predict faster platelet engraftment. However, additional studies are necessary for better understanding of engraftment kinetics to improve the success of APBSCT.

    Matched MeSH terms: Kinetics
  2. Kong H, Saman N, Tee PN, Cheu SC, Song ST, Johari K, et al.
    Environ Sci Pollut Res Int, 2019 Apr;26(11):11140-11152.
    PMID: 30796666 DOI: 10.1007/s11356-019-04248-5
    The aim of this work is to convert agroforestry residue to a novel adsorbent (M-1CTA-SDS-BT) used for adsorptive benzene sequestration from aqueous solution. In this study, the anionic surfactant-coated-cationized banana trunk was synthesized and characterized for batch adsorption of benzene from aqueous solution. The surface morphology, surface chemistry, surface area, and pore properties of the synthesized adsorbents were examined. It was proven that surface cationization successfully increased the benzene adsorption capacity of sodium dodecyl sulfate-coated adsorbents. The Langmuir isotherm model satisfactorily described the equilibrium adsorption data. The maximum benzene adsorption capacity (qmax) of 468.19 μmol/g was attained. The kinetic data followed the pseudo-second-order kinetic model in which the rate-limiting step was proven to be the film diffusion. The batch-adsorbent regeneration results indicated that the M-1CTA-SDS-BT could withstand at least five adsorption/desorption cycles without drastic adsorption capacity reduction. The findings demonstrated the adsorptive potential of agroforestry-based adsorbent as a natural and cheap material for benzene removal from contaminated water.
    Matched MeSH terms: Kinetics
  3. Shehu D, Alias Z
    FEBS Open Bio, 2019 03;9(3):408-419.
    PMID: 30868049 DOI: 10.1002/2211-5463.12405
    A glutathione S-transferase (GST) with a potential dehalogenation function against various organochlorine substrates was identified from a polychlorobiphenyl (PCB)-degrading organism, Acidovorax sp. KKS102. A homolog of the gene BphK (biphenyl upper pathway K), named BphK-KKS, was cloned, purified and biochemically characterized. Bioinformatic analysis indicated several conserved amino acids that participated in the catalytic activity of the enzyme, and site-directed mutagenesis of these conserved amino acids revealed their importance in the enzyme's catalytic activity. The wild-type and mutant (C10F, K107T and A180P) recombinant proteins displayed wider substrate specificity. The wild-type recombinant GST reacted towards 1-chloro-2,4-dinitrobenzene (CDNB), ethacrynic acid, hydrogen peroxide and cumene hydroperoxide. The mutated recombinant proteins, however, showed significant variation in specific activities towards the substrates. A combination of a molecular docking study and a chloride ion detection assay showed potential interaction with and a dechlorination function against 2-, 3- and 4-chlorobenzoates (metabolites generated during PCB biodegradation) in addition to some organochlorine pesticides (dichlorodiphenyltrichloroethane, endosulfan and permethrin). It was demonstrated that the behavior of the dechlorinating activities varied among the wild-type and mutant recombinant proteins. Kinetic studies (using CDNB and glutathione) showed that the kinetic parameters Km, Vmax, Kcat and Km/Kcat were all affected by the mutations. While C10F and A180P mutants displayed an increase in GST activity and the dechlorination function of the enzyme, the K107T mutant displayed variable results, suggesting a functional role of Lys107 in determining substrate specificity of the enzyme. These results demonstrated that the enzyme should be valuable in the bioremediation of metabolites generated during PCB biodegradation.
    Matched MeSH terms: Kinetics
  4. Lai YH, Puspanadan S, Lee CK
    Biotechnol Prog, 2019 05;35(3):e2798.
    PMID: 30828976 DOI: 10.1002/btpr.2798
    Present study aims to optimize the production of starch and total carbohydrates from Arthrospira platensis. Growing concerns toward unprecedented environmental issues associated with plastic pollution has created a tremendous impetus to develop new biomaterials for the production of bioplastic. Starch-based biopolymers from algae serve as sustainable feedstock for thermoplastic starch production due to their abundant availability and low cost. A. platensis was cultivated in Zarrouk's medium at 32 ± 1°C and exposed to red light with a photoperiod of 12:12 hr light/dark. Growth kinetics studies showed that the maximum specific growth rate (μmax ) obtained was 0.059 day-1 with the doubling time (td ) of 11.748 days. Subsequently, Zarrouk's medium with different concentrations of sulfur, phosphorus and nitrogen was prepared to establish the nutrient-limiting conditions to enhance the accumulation of starch and total carbohydrates. In this study, the highest starch accumulated was 6.406 ± 0.622 mg L-1 under optimized phosphorus limitation (0.025 g L-1 ) conditions. Nitrogen limitation (0.250 g L-1 ) results demonstrated significant influenced (p 
    Matched MeSH terms: Kinetics
  5. Thavoncharoensub N, Maruyama K, Heh CH, Hoong Leong K, Shi H, Shigematsu Y, et al.
    PMID: 30929604 DOI: 10.1080/15257770.2019.1586919
    8-OxodGTP is generated by the reaction between dGTP and reactive oxygen species and a considered mutagenic nucleotide. It can be incorporated into the duplex DNA during replication processes by the DNA polymerase, and thus the repair enzyme removes oxodGTP from the nucleotide pools in living cells. On the other hand, the γ-modified triphosphates show interesting properties for use as biological tools. Therefore, the γ-N-pyrenylalkyl-oxodGTP derivatives were synthesized and their effect on the enzymatic reactions were evaluated. The γ-N-pyrenylmethyl-oxodGTP was found to be accepted by the DNA polymerase just like oxodGTP, but showed a competitive inhibition property for the human oxodGTPase.
    Matched MeSH terms: Kinetics
  6. Siddiqa AJ, Shrivastava NK, Ali Mohsin ME, Abidi MH, Shaikh TA, El-Meligy MA
    Colloids Surf B Biointerfaces, 2019 Jul 01;179:445-452.
    PMID: 31005739 DOI: 10.1016/j.colsurfb.2019.04.014
    This paper focuses on the development of a drug delivery system for systemically controlled release of a poorly soluble drug, letrozole. The work meticulously describes the preparation and characterizations of 2-hydroxyethyl methacrylate (HEMA) polymerization onto hydrophilic acrylamide grafted low-density polyethylene (AAm-g-LDPE) surface for targeted drug release system. The surface morphology and thickness measurement of coated pHEMA layer were measured using scanning electron microscopy (SEM). The swelling study was done in deionized (DI) water and simulated uterine fluid (SUF, pH = 7.6). In vitro release of letrozole from the system was performed in SUF. Further, the release kinetics of letrozole from the system was studied using different mathematical models. The results, suggest that the rate of drug release can be altered by varying the concentrations of cross-linker in pHEMA. The optimized sample released 72% drug at the end of 72 h of measurement.
    Matched MeSH terms: Kinetics
  7. Zaid RM, Mishra P, Wahid ZA, Sakinah AMM
    Int J Biol Macromol, 2019 Aug 01;134:361-367.
    PMID: 31059740 DOI: 10.1016/j.ijbiomac.2019.03.143
    In the present study, high-methoxyl pectin (HMP) was extracted from Hylocereus polyrhizus peel's using physico-chemical process. In addition, the hypolipidemic activity of HMP was investigated at different concentration and time corresponding to its adsorption ability. FTIR and contact angle analysis were used to determine the sorbent characterization. A high degree of esterification (63.8%) and the contact angle (95.5°) confirmed hydrophobic nature and resulting bad wetting of the HMP extract, respectively. The methoxyl content in the pectin acted as an affinity-precursor of the pectin towards cholesterol due to its increased hydrophobicity. The maximum equilibrium uptake capacity of cholesterol of 370.5mg/g (0.96mmol/g) was observed by HMP. The experimental data showed good fitting for Freundlich isotherm equation and followed pseudo-first-order kinetic model with a correlation coefficient (R2) of 0.89-0.97 due to physisorption mechanism. Intra-particle model confirmed that the cholesterol sorption rate by HMP was significantly influenced by external mass transfer (surface diffusion) and intra-particle diffusion (diffusion control). It was also revealed that the HMP extracted from Hylocereus polyrhizus peels possess a high affinity towards cholesterol, making it an ideal hypolipidemic agent.
    Matched MeSH terms: Kinetics
  8. Hassan RA, Heng LY, Ahmad A, Tan LL
    PLoS One, 2019;14(4):e0214580.
    PMID: 30990847 DOI: 10.1371/journal.pone.0214580
    A potentiometric whole cell biosensor based on immobilized marine bacterium, Pseudomonas carrageenovora producing κ-carrageenase and glycosulfatase enzymes for specific and direct determination of κ-carrageenan, is described. The bacterial cells were immobilized on the self-plasticized hydrogen ion (H+)-selective acrylic membrane electrode surface to form a catalytic layer. Hydrogen ionophore I was incorporated in the poly(n-butyl acrylate) [poly(nBA)] as a pH ionophore. Catalytic decomposition of κ-carrageenan by the bienzymatic cascade reaction produced neoagarobiose, an inorganic sulfate ion and a proton. The latter was detectable by H+ ion transducer for indirect potentiometric quantification of κ-carrageenan concentration. The use of a disposable screen-printed Ag/AgCl electrode (SPE) provided no cleaning requirement and enabled κ-carrageenan detection to be carried out conveniently without cross contamination in a complex food sample. The SPE-based microbial biosensor response was found to be reproducible with high reproducibility and relative standard deviation (RSD) at 2.6% (n = 3). The whole cell biosensor demonstrated a broad dynamic linear response range to κ-carrageenan from 0.2-100 ppm in 20 mM phosphate buffer saline (PBS) at pH 7.5 with a detection limit at 0.05 ppm and a Nernstian sensitivity of 58.78±0.87 mV/decade (R2 = 0.995). The biosensor showed excellent selectivity towards κ-carrageenan compared to other types of carrageenans tested e.g. ι-carrageenan and λ-carrageenan. No pretreatment to the food sample was necessary when the developed whole cell biosensor was employed for direct assay of κ-carrageenan in dairy product.
    Matched MeSH terms: Kinetics
  9. Sutirman ZA, Sanagi MM, Abd Karim KJ, Abu Naim A, Wan Ibrahim WA
    Int J Biol Macromol, 2019 Jul 15;133:1260-1267.
    PMID: 31047925 DOI: 10.1016/j.ijbiomac.2019.04.188
    Grafting of crosslinked chitosan with monomer, N-vinyl-2-pyrrolidone, has been carried out to investigate its adsorption capacity toward Orange G (OG) from aqueous solutions. The adsorption performance of modified chitosan (cts(x)-g-PNVP) was examined and compared with that of the unmodified chitosan. The effects of initial pH, contact time and initial dye concentration were investigated in a batch system. The experimental data were correlated with the Langmuir and Freundlich isotherm models. The maximum adsorption capacity of cts(x)-g-PNVP (63.7mgg-1) based on Langmuir equation was relatively higher than that of the unmodified chitosan (1.7mgg-1). The kinetic studies showed that the adsorption process was consistent with the pseudo-second order kinetic model. Interaction mechanisms between OG and cts(x)-g-PNVP were also proposed. The overall results suggested that the prepared cts(x)-g-PNVP stands a good candidate as adsorbent for removal of anionic dye from aqueous solutions.
    Matched MeSH terms: Kinetics
  10. Myles KM, Pierro DJ, Olson KE
    J Med Entomol, 2004 Jan;41(1):95-106.
    PMID: 14989352
    Within mosquitoes, arboviruses encounter barriers to infection and dissemination that are critical determinants of vector competence. The molecular mechanisms responsible for these barriers have yet to be elucidated. The prototype Sindbis (SIN) strain, AR339, and viruses derived from this strain, such as TR339 virus, have limited infection and transmission potential in the medically important arthropod vector, Aedes aegypti (L.). However, the Malaysian SIN virus strain, MRE16, disseminates in nearly 100% of Ae. aegypti 14 d after oral infection. Here, we compare the spatial and temporal infection patterns of MRE16 and TR339 viruses in Ae. aegypti. The results indicate that a midgut escape barrier is primarily responsible for the significantly lower dissemination and transmission potentials observed after oral infection with TR339 virus. MRE16 and TR339 viruses now represent a well-characterized model system for the further study of virus determinants of vector infection, particularly determinants affecting the midgut escape barrier in Ae. aegypti.
    Matched MeSH terms: Kinetics
  11. Oyekanmi AA, Ahmad A, Hossain K, Rafatullah M
    PLoS One, 2019;14(5):e0216878.
    PMID: 31091269 DOI: 10.1371/journal.pone.0216878
    The adsorption of rhodamine B (RhB) using acid modified banana peels has been examined. Chemical characteristics of the adsorbents were observed in order to determine active functional groups. The major functional groups on the surface were OH, C = O, C = C and C-O-C. Interactions between operational parameters were studied using the central composite design (CCD) of response surface methodology (RSM). The predictions of the model output indicated that operational factors influenced responses at a confidence level of 95% (P<0.05). The optimum conditions for adsorption were pH 2 at a 0.2 g/L dose within 60 minutes of contact time. Isotherm studies were carried out using the optimized process variables. The data revealed that RhB adsorption fitted the Langmuir isotherm equation while the reduction of COD followed the Freundlich isotherm. Kinetic experiments fitted the pseudo second order model for RhB removal and COD reduction. The adsorption mechanism was not the only rate controlling step. Diffusion through the boundary layer described the pattern of adsorption.
    Matched MeSH terms: Kinetics
  12. Jawad AH, Norrahma SSA, Hameed BH, Ismail K
    Int J Biol Macromol, 2019 Aug 15;135:569-581.
    PMID: 31150675 DOI: 10.1016/j.ijbiomac.2019.05.127
    In this work, chitosan (Chi) was cross-linked with glyoxal (Gly) and deposited onto glass plate to be a superior adsorbent film for two structurally different reactive orange 16 (RO-16) and methyl orange (MO) dyes by using non-conventional adsorption system without filtration process. The characterizations indicate that the cross-linked chitosan-glyoxal (Chi-Gly) film has a low swelling index, high adherence strength on glass plate, amine group (NH2) content was 32.52%, and pHpzc of ∼6.0 indicating a negative surface charge occurs above pHpzc. The adsorption isotherm data of RO-16 and MO by Chi-Gly film were in agreement with Langmuir isotherm, with maximum adsorption capacities of 1554.3 mg/g and 1451.9 mg/g, respectively. The pseudo-first-order kinetic model best described the kinetic data. The adsorption process was spontaneous and exothermic in nature at Chi-Gly film thickness of 8.55 μm, and pH ~3. The mechanism of adsorption included mainly electrostatic attractions, dipole-dipole hydrogen bonding interactions, n-π stacking attractions, and Yoshida H-bonding. This study reveals that immobilized Chi-Gly film as a good candidate for adsorption of reactive and acid dyes as it does not require any filtration process and adsorbent recovery during and post-adsorption process.
    Matched MeSH terms: Kinetics
  13. Nasir AM, Goh PS, Abdullah MS, Ng BC, Ismail AF
    Chemosphere, 2019 Oct;232:96-112.
    PMID: 31152909 DOI: 10.1016/j.chemosphere.2019.05.174
    Heavy metal contamination in aqueous system has attracted global attention due to the toxicity and carcinogenicity effects towards living bodies. Among available removal techniques, adsorptive removal by nanosized materials such as metal oxide, metal organic frameworks, zeolite and carbon-based materials has attracted much attention due to the large active surface area, large number of functional groups, high chemical and thermal stability which led to outstanding adsorption performance. However, the usage of nanosized materials is restricted by the difficulty in separating the spent adsorbent from aqueous solution. The shift towards the use of adsorptive composite membrane for heavy metal ions removal has attracted much attention due to the synergistic properties of adsorption and filtration approaches in a same chamber. Thus, this review critically discusses the development of nanoadsorbents and adsorptive nanocomposite membranes for heavy metal removal over the last decade. The adsorption mechanism of heavy metal ions by the advanced nanoadsorbents is also discussed using kinetic and isotherm models. The challenges and future prospect of adsorptive membrane technology for heavy metal removal is presented at the end of this review.
    Matched MeSH terms: Kinetics
  14. Altowayti WAH, Allozy HGA, Shahir S, Goh PS, Yunus MAM
    Environ Sci Pollut Res Int, 2019 Oct;26(28):28737-28748.
    PMID: 31376124 DOI: 10.1007/s11356-019-06059-0
    Several parts of the world have been facing the problem of nitrite and nitrate contamination in ground and surface water. The acute toxicity of nitrite has been shown to be 10-fold higher than that of nitrate. In the present study, aminated silica carbon nanotube (ASCNT) was synthesised and tested for nitrite removal. The synergistic effects rendered by both amine and silica in ASCNT have significantly improved the nitrite removal efficiency. The IEP increased from 2.91 for pristine carbon nanotube (CNT) to 8.15 for ASCNT, and the surface area also increased from 178.86 to 548.21 m2 g-1. These properties have promoted ASCNT a novel adsorbent to remove nitrite. At optimum conditions of 700 ppm of nitrite concentration at pH 7 and 5 h of contact with 15 mg of adsorbent, the ASCNT achieved the maximal loading capacity of 396 mg/g (85% nitrite removal). The removal data of nitrite onto ASCNT fitted the Langmuir isotherm model better than the Freundlich isotherm model with the highest regression value of 0.98415, and also, the nonlinear analysis of kinetics data showed that the removal of nitrite followed pseudo-second-order kinetic. The positive values of both ΔS° and ΔH° suggested an endothermic reaction and an increase in randomness at the solid-liquid interface. The negative ΔG° values indicated a spontaneous adsorption process. The ASCNT was characterised using FESEM-EDX and FTIR, and the results obtained confirmed the removal of nitrite. Based on the findings, ASCNT can be considered as a novel and promising candidate for the removal of nitrite ions from wastewater.
    Matched MeSH terms: Kinetics
  15. Kusrini E, Usman A, Sani FA, Wilson LD, Abdullah MAA
    Environ Monit Assess, 2019 Jul 10;191(8):488.
    PMID: 31292792 DOI: 10.1007/s10661-019-7634-6
    This paper presents the adsorption capacity of a biosorbent derived from the inner part of durian (Durio zibethinus) rinds, which are a low-cost and abundant agro-waste material. The durian rind sorbent has been successfully utilized to remove lanthanum (La) and yttrium (Y) ions from their binary aqueous solution. The effects of several adsorption parameters including contact time, pH, concentrations of La and Y, and temperature on the removal of La and Y ions were investigated. The adsorption isotherm and kinetics of the metal ions were also evaluated in detail. Both La and Y ions were efficiently adsorbed by the biosorbent with optimum adsorption capacity as high as 71 mg La and 35 mg Y per gram biosorbent, respectively. The simultaneous adsorption of La and Y ions follows Langmuir isotherm model, due to the favorable chelation and strong chemical interactions between the functional groups on the surface of the biosorbent and the metal ions. The addition of oxygen content after adsorption offers an interpretation that the rare-earth metal ions are chelated and incorporated most probably in the form of metal oxides. With such high adsorption capacity of La and Y ions, the durian rind sorbent could potentially be used to treat contaminated wastewater containing La and Y metal ions, as well as for separating and extracting rare-earth metal ions from crude minerals.
    Matched MeSH terms: Kinetics
  16. Al-Ahdal SA, Ahmad Kayani AB, Md Ali MA, Chan JY, Ali T, Adnan N, et al.
    Int J Mol Sci, 2019 Jul 23;20(14).
    PMID: 31340481 DOI: 10.3390/ijms20143595
    We employed dielectrophoresis to a yeast cell suspension containing amyloid-beta proteins (Aβ) in a microfluidic environment. The Aβ was separated from the cells and characterized using the gradual dissolution of Aβ as a function of the applied dielectrophoretic parameters. We established the gradual dissolution of Aβ under specific dielectrophoretic parameters. Further, Aβ in the fibril form at the tip of the electrode dissolved at high frequency. This was perhaps due to the conductivity of the suspending medium changing according to the frequency, which resulted in a higher temperature at the tips of the electrodes, and consequently in the breakdown of the hydrogen bonds. However, those shaped as spheroidal monomers experienced a delay in the Aβ fibril transformation process. Yeast cells exposed to relatively low temperatures at the base of the electrode did not experience a positive or negative change in viability. The DEP microfluidic platform incorporating the integrated microtip electrode array was able to selectively manipulate the yeast cells and dissolve the Aβ to a controlled extent. We demonstrate suitable dielectrophoretic parameters to induce such manipulation, which is highly relevant for Aβ-related colloidal microfluidic research and could be applied to Alzheimer's research in the future.
    Matched MeSH terms: Kinetics
  17. Van Tran T, Nguyen DTC, Nguyen HT, Nanda S, Vo DN, Do ST, et al.
    Environ Sci Pollut Res Int, 2019 Sep;26(27):28106-28126.
    PMID: 31363978 DOI: 10.1007/s11356-019-06011-2
    The occurrence and fate of antibiotic compounds in water can adversely affect human and animal health; hence, the removal of such substrates from soil and water is indispensable. Herein, we described the synthesis method of mesoporous carbon (MPC) via the pyrolysis route from a coordination polymer Fe-based MIL-53 (or MIL-53, shortly). The MPC structure was analyzed by several physical techniques such as SEM, TEM, BET, FT-IR, VSM, and XRD. The response surface methodology (RSM) was applied to find out the effects of initial concentration, MPC dosage, and pH on the removal efficiency of trimethoprim (TMP) and sulfamethoxazole (SMX) antibiotics in water. Under the optimized conditions, the removal efficiencies of TMP and SMX were found to be 87% and 99%, respectively. Moreover, the adsorption kinetic and isotherm studies showed that chemisorption and the monolayer adsorption controlled the adsorption process. The leaching test and recyclability studies indicated that the MPC structure was stable and can be reused for at least four times without any considerable change in the removal efficiency. Plausible adsorption mechanisms were also addressed in this study. Because of high maximum adsorption capacity (85.5 mg/g and 131.6 mg/g for TMP and SMX, respectively) and efficient reusability, MPC is recommended to be a potential adsorbent for TMP and SMX from water media.
    Matched MeSH terms: Kinetics
  18. Pandey P, Chellappan DK, Tambuwala MM, Bakshi HA, Dua K, Dureja H
    Int J Biol Macromol, 2019 Dec 01;141:596-610.
    PMID: 31494160 DOI: 10.1016/j.ijbiomac.2019.09.023
    The most common cause of deaths due to cancers nowadays is lung cancer. The objective of this study was to prepare erlotinib loaded chitosan nanoparticles for their anticancer potential. To study the effect of formulation variables on prepared nanoparticles using central composite design. Erlotinib loaded chitosan nanoparticles were prepared by ionic gelation method using probe sonication technique. It was found that batch NP-7 has a maximum loading capacity and entrapment efficiency with a particle size (138.5 nm) which is ideal for targeting solid tumors. Analysis of variance was applied to the particle size, entrapment efficiency and percent cumulative drug release to study the fitting and the significance of the model. The batch NP-7 showed 91.57% and 39.78% drug release after 24 h in 0.1 N hydrochloric acid and Phosphate Buffer (PB) pH 6.8, respectively. The IC50 value of NP-7 evaluated on A549 Lung cancer cells was found to be 6.36 μM. The XRD of NP-7 displayed the existence of erlotinib in the amorphous pattern. The optimized batch released erlotinib slowly in comparison to the marketed tablet formulation. Erlotinib loaded chitosan nanoparticles were prepared successfully using sonication technique with suitable particle size, entrapment efficiency and drug release. The formulated nanoparticles can be utilized for the treatment of lung cancer.
    Matched MeSH terms: Kinetics
  19. Mustafa SM, Chua LS, El-Enshasy HA
    Molecules, 2019 Jun 26;24(13).
    PMID: 31247970 DOI: 10.3390/molecules24132357
    The issues of lactose intolerance and vegetarianism have encouraged the introduction of non-dairy fermented food into the market. Therefore, this study aims to evaluate the effect of agitation speed on the bioactive compounds and functional characteristics of probioticated pomegranate juice. Pomegranate juice was fermented with Lactobacillus casei at different agitation speeds ranging from 0 (microaerophilic) to 150 rpm at 37 °C. The functional properties of probioticated pomegranate juice were evaluated in terms of growth (biomass), lactic acid production, antioxidant activity, total phenolic content, and key metabolites using LC-MS/MS. The growth kinetics of fermentation was monitored at the optimal condition using one factor at a time method. High cell growth (3.58 × 1010 cfu/mL or 7.9 gL-1) was observed for L. casei probioticated pomegranate juice agitated at 0 rpm. The findings of this study reveal the potential of pomegranate juice as a medium for L. casei cultivation without nutrient supplementation. The improvement of antioxidant activity in the probioticated juice could be due to the increment of quercetin-3-glucoside. Therefore, L. casei grew well in pomegranate juice with a high cell viability and antioxidant activity at a non-agitated condition. Probioticated pomegranate juice is a potentially functional drink.
    Matched MeSH terms: Kinetics
  20. Rafique R, Khan KM, Arshia, Kanwal, Chigurupati S, Wadood A, et al.
    Bioorg Chem, 2020 01;94:103195.
    PMID: 31451297 DOI: 10.1016/j.bioorg.2019.103195
    The current study describes the discovery of novel inhibitors of α-glucosidase and α-amylase enzymes. For that purpose, new hybrid analogs of N-hydrazinecarbothioamide substituted indazoles 4-18 were synthesized and fully characterized by EI-MS, FAB-MS, HRFAB-MS, 1H-, and 13C NMR spectroscopic techniques. Stereochemistry of the imine double bond was established by NOESY measurements. All derivatives 4-18 with their intermediates 1-3, were evaluated for in vitro α-glucosidase and α-amylase enzyme inhibition. It is worth mentioning that all synthetic compounds showed good inhibition potential in the range of 1.54 ± 0.02-4.89 ± 0.02 µM for α-glucosidase and for α-amylase 1.42 ± 0.04-4.5 ± 0.18 µM in comparison with the standard acarbose (IC50 value of 1.36 ± 0.01 µM). In silico studies were carried out to rationalize the mode of binding interaction of ligands with the active site of enzymes. Moreover, enzyme inhibitory kinetic characterization was also performed to understand the mechanism of enzyme inhibition.
    Matched MeSH terms: Kinetics
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