Displaying publications 81 - 100 of 189 in total

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  1. Purification of recombinant hepatitis B core antigen from unclarified Escherichia coli feedstock using phage-immobilized expanded bed adsorption chromatography
    Ng MY, Tan WS, Tey BT
    J Chromatogr B Analyt Technol Biomed Life Sci, 2012 Aug 15;903:60-7.
    PMID: 22819608 DOI: 10.1016/j.jchromb.2012.06.043
    Fusion M13 phage with disulfide constrained heptapeptide, C-WSFFSNI-C, inserted into the minor coat protein (gpIII), has been selected in the current study as ligand in direct purification of hepatitis B core antigen (HBcAg) from unclarified Escherichia coli (E. coli) feedstock. The selected fusion phage showed strong association with the surface of the core particle. In the present study, this fusion M13 phage was immobilized onto Streamline base matrix via epoxy activation and used as adsorbent to capture HBcAg from crude E. coli homogenate. The maximum binding capacity for the adsorbent was 3.76 mg/mL with equilibrium coefficient of 1.83 mg/mL. Due to the slow uptake rate of HBcAg by M13 phage-immobilized adsorbents, a modified EBAC operation with recirculation of feedstock into the expanded bed has been investigated in this study. The introduction of feedstock recirculation has led to an 18% increase in yield; however, the purity of the eluted product was reduced by 15% compared with typical EBAC operation. The level of antigenicity exhibited by the core particles purified by both EBAC operations employed in the present study was comparable to that purified using sucrose ultracentrifugation.
    Matched MeSH terms: Urea
  2. Fulltext Characterization of modified tapioca starch solutions and their sprays for high temperature coating applications
    Naz MY, Sulaiman SA, Ariwahjoedi B, Shaari KZ
    ScientificWorldJournal, 2014;2014:375206.
    PMID: 24592165 DOI: 10.1155/2014/375206
    The objective of the research was to understand and improve the unusual physical and atomization properties of the complexes/adhesives derived from the tapioca starch by addition of borate and urea. The characterization of physical properties of the synthesized adhesives was carried out by determining the effect of temperature, shear rate, and mass concentration of thickener/stabilizer on the complex viscosity, density, and surface tension. In later stage, phenomenological analyses of spray jet breakup of heated complexes were performed in still air. Using a high speed digital camera, the jet breakup dynamics were visualized as a function of the system input parameters. The further analysis of the grabbed images confirmed the strong influence of the input processing parameters on full cone spray patternation. It was also predicted that the heated starch adhesive solutions generate a dispersed spray pattern by utilizing the partial evaporation of the spraying medium. Below 40°C of heating temperature, the radial spray cone width and angle did not vary significantly with increasing Reynolds and Weber numbers at early injection phases leading to increased macroscopic spray propagation. The discharge coefficient, mean flow rate, and mean flow velocity were significantly influenced by the load pressure but less affected by the temperature.
    Matched MeSH terms: Urea/chemistry
  3. Fulltext Exploring pineapple peel hydrolysate as a sustainable carbon source for xylitol production
    Nasoha NZ, Luthfi AAI, Roslan MF, Hariz HB, Bukhari NA, Manaf SFA
    Sci Rep, 2023 Nov 07;13(1):19284.
    PMID: 37935748 DOI: 10.1038/s41598-023-46061-8
    This study explores utilizing pineapple peel (PP) hydrolysate as a promising carbon source for xylitol production, covering scopes from the pre-treatment to the fermentation process. The highest xylose concentration achieved was around 20 g/L via mild acid hydrolysis (5% nitric acid, 105 °C, 20-min residence time) with a solid loading of 10%. Two sets fermentability experiments were carried out of varying pH levels in synthetic media that includes acetic acid as the main inhibitors and hydrolysate supplemented with diverse nitrogen source. The results revealed that pH 7 exhibited the highest xylitol production, yielding 0.35 g/g. Furthermore, urea was found to be a highly promising and cost-effective substitute for yeast extract, as it yielded a comparable xylitol production of 0.31 g/g with marginal difference of only 0.01 g/g compared to yeast extract further highlights the viability of urea as the preferred option for reducing xylitol production cost. The absence of a significant difference between the synthetic media and hydrolysate, with only a marginal variance of 0.35 to 0.32 g/g, implies that acetic acid is indeed the primary constraint in xylitol production using PP hydrolysate. The study sheds light on PP biomass's potential for xylitol production, aligning economic benefits with environmental sustainability and waste management.
    Matched MeSH terms: Urea
  4. Fulltext Hypertension influences the exponential progression of inflammation and oxidative stress in streptozotocin-induced diabetic kidney
    Muthaian R, Pakirisamy RM, Parasuraman S, Raveendran R
    J Pharmacol Pharmacother, 2017 2 7;7(4):159-164.
    PMID: 28163536 DOI: 10.4103/0976-500X.195898
    OBJECTIVE: To investigate the association of hypertension coexisting with diabetes mellitus with oxidative stress and inflammation in the kidneys of streptozotocin (STZ)-induced diabetic rats.

    MATERIALS AND METHODS: Male Wistar rats were used for the experiments. Blood glucose (BG), urea, blood pressure (BP), and heart rate (HR) were analyzed before and 48 h after STZ injection. Further, these parameters were monitored up to 3 months of diabetes induction. Subsequently, the inflammatory markers (C-reactive protein, tumor necrosis factor-alpha, and nitrate) and oxidative stress markers were estimated after 3 months of diabetes induction in the kidney homogenate. Histological analysis of renal tissue was also carried out.

    RESULTS: Linear elevation of BG, urea, mean arterial pressure (MAP), and HR was observed up to 3 months of diabetes induction. In the same manner, inflammatory and oxidative stress markers were also found to be significantly increased. Notably, the histological analysis revealed the signs of nephropathy such as increased mesangial cell number, thickness of basement membrane, and renal artery. Inflammatory and oxidative stress markers positively correlated with elevated BP and BG, but the correlation was better with BP rather than BG.

    CONCLUSION: Hypertension has a strong implication in the increased oxidative stress and inflammation of diabetic kidney at the very early stage of diabetes mellitus.

    Matched MeSH terms: Urea
  5. Effects of the aqueous extracts of rhodamnia cinerea on metabolic indices and sorbitol-related complications in type 2 diabetic rats
    Mustapha Umar Imam, Sasikala M. Chinnappan, Maznah Ismail
    Sains Malaysiana, 2017;46:589-595.
    There is growing interest in the use of plant bioresources for managing type 2 diabetes. In this study, Rhodamnia cinerea, which is used traditionally to manage diseases in Malaysia, was explored for its antidiabetic effects. Type 2 diabetic rats were managed for 4 weeks using aqueous extract of R. cinerea or quercetin. Weights and fasting glucose were measured weekly, while serum lipid profiles, insulin, antioxidant status, urea, creatinine and liver enzymes were assayed at the end. Sorbitol contents, antioxidant capacities and aldose reductase activities of the kidney, lens and sciatic nerve were also assessed. The results showed that the aqueous extract of R. Cinerea mainly contained Myricitrin and it reduced glycemia (p>0.05), lipid profiles (p<0.05), F2-isoprostanes (p<0.05) and overall metabolic condition of type 2 diabetic rats. R. cinerea also attenuated sorbitol contents of the nerve (p<0.05) and kidney (p<0.05), partly through regulating the activity of aldose reductase (p<0.05 for nerve) and sorbitol dehydrogenase (p<0.05 for kidney) in comparison with diabetic untreated group. Quercetin is a known aldose reductase inhibitor and can improve several metabolic indices related to Type 2 diabetes. In this study, the results of R. cinerea were comparable to or better than those of quercetin, suggesting that R. cinerea extract can be a good candidate for managing Type 2 diabetes and its complications related to sorbitol accumulation.
    Matched MeSH terms: Urea
  6. Fulltext A Rare Cause of Acute Kidney Injury: Primary Renal Lymphoma in a Patient with Human Immunodeficiency Virus
    Mustafar R, Kamaruzaman L, Chien BH, Yahaya A, Mohd Nasir N, Mohd R, et al.
    Case Rep Med, 2018;2018:8425985.
    PMID: 30186328 DOI: 10.1155/2018/8425985
    We reported a case of primary renal lymphoma (PRL) presented with non-oliguric acute kidney injury and bilateral kidney infiltrates in an individual with human immunodeficiency virus (HIV) disease. Acute kidney injury secondary to lymphoma infiltrates is very rare (less than 1% of hematological malignancy). A 37-year-old gentleman with underlying human immunodeficiency virus (HIV) disease was on combined antiretroviral therapy since diagnosis. He presented to our center with uremic symptoms and gross hematuria. Clinically, bilateral kidneys massively enlarged and were ballotable. Blood investigations showed hemoglobin of 3.7 g/L, urea of 65.6 mmol/L, and serum creatinine of 1630 µmol/L with hyperkalemia and metabolic acidosis. An urgent hemodialysis was initiated, and he was dependent on regular hemodialysis subsequently. Computed tomography renal scan showed diffuse nonenhancing hypodense lesion in both renal parenchyma. Diagnosis of diffuse large B cell lymphoma with germinal center type, CD20 positive, and proliferative index 95% was confirmed via renal biopsy, and there was no bone marrow infiltrates. Unfortunately, the patient succumbs prior to initiation of chemotherapy.
    Matched MeSH terms: Urea
  7. Fulltext A Study of Dielectric Properties of Proteinuria between 0.2 GHz and 50 GHz
    Mun PS, Ting HN, Ong TA, Wong CM, Ng KH, Chong YB
    PLoS One, 2015;10(6):e0130011.
    PMID: 26066351 DOI: 10.1371/journal.pone.0130011
    This paper investigates the dielectric properties of urine in normal subjects and subjects with chronic kidney disease (CKD) at microwave frequency of between 0.2 GHz and 50 GHz. The measurements were conducted using an open-ended coaxial probe at room temperature (25°C), at 30°C and at human body temperature (37°C). There were statistically significant differences in the dielectric properties of the CKD subjects compared to those of the normal subjects. Statistically significant differences in dielectric properties were observed across the temperatures for normal subjects and CKD subjects. Pearson correlation test showed the significant correlation between proteinuria and dielectric properties. The experimental data closely matched the single-pole Debye model. The relaxation dispersion and relaxation time increased with the proteinuria level, while decreasing with the temperature. As for static conductivity, it increased with proteinuria level and temperature.
    Matched MeSH terms: Urea/chemistry*
  8. Fulltext Crystal structure of 3-methyl-pyridine-2-carbaldehyde 4-methyl-thio-semi-carba-zone monohydrate
    Mokhtaruddin NS, Ravoof TB, Tahir MI, Tiekink ER
    Acta Crystallogr E Crystallogr Commun, 2015 Apr 1;71(Pt 4):o253-4.
    PMID: 26029441 DOI: 10.1107/S2056989015005034
    In the title hydrate, C9H12N4S·H2O (systematic name: 3-methyl-1-{(E)-[(3-methyl-pyridin-2-yl)methyl-idene]amino}-thio-urea monohydrate), a small twist is noted between the pyridine ring and the rest of the organic mol-ecule [dihedral angle = 6.96 (5)°]. The imine and pyridine N atoms are syn, and the amine H atoms are anti. The latter arrangement allows for the formation of an intra-molecular N-H⋯N(imine) hydrogen bond. Both the N-bonded H atoms form hydrogen bonds to symmetry-related water mol-ecules, and the latter forms O-H hydrogen bonds with the pyridine N and thione S atoms. These inter-actions lead to supra-molecular layers that stack along the a-axis direction with no specific inter-actions between them.
    Matched MeSH terms: Urea
  9. Field evaluation of newly-developed controlled release fertilizer on rice production and nitrogen uptake
    Mohammad Mu'az Hashim, Mohd Khanif Yusop, Radziah Othman, Samsuri Abd. Wahid
    Sains Malaysiana, 2017;46:925-932.
    Implementation of sound fertilizer management in rice cultivation is essential in optimizing productivity and profitability. The use of controlled release fertilizer (CRF) to improve crop production in various cropping systems has been widely explored, with new approaches and materials continually being studied to produce new CRF. A field study was carried out to determine the efficiency of local CRFs on rice production and N uptake using MR220 CL1 rice variety. Ten different types of CRFs consisting of two groups namely biochar impregnated urea (BIU 300-5, BIU 300-10, BIU 700-5 and BIU 700-10) and palm stearin (PS) coated urea with nitrification inhibitors (PS, PS+DMPP-100, PS+DMPP-50, PS+DMPP-150, PS+Cu and PS+Zn) were used as treatments. Plant height, SPAD reading, 1000-grain weight and harvest index (HI) showed significant improvement in rice treated with both biochar impregnated and palm stearin coated urea. With respect to grain yield, BIU 300-10, BIU 700-5, BIU 700-10, PS+DMPP-100, PS+DMPP-50, PS+DMPP-150 and PS+Cu treatments significantly increased rice yield. The CRFs mostly showed significantly higher N uptake in rice, especially in rice grains, however, there was no significant difference among treatments in soil residual ammonium (NH4+-N). The newly-developed CRFs showed huge potential as an alternative for common urea, especially BIU 700-5, BIU 700-10, PS+DMPP-100 and PS+DMPP-50, in increasing rice grain yield. With proper approaches, these CRFs can contribute in improving rice production to provide sufficient food for ever increasing population.
    Matched MeSH terms: Urea
  10. Effects of medicated and non-medicated multi-nutrient block supplementation on gastrointestinal parasite infestation and blood hematological parameters of lactating saanen goats
    Mira Panadi, Nor Dini Rusli, Khairiyah Mat, Wan Zahari Mohamed
    Sains Malaysiana, 2018;47:1447-1453.
    In a 90-day feeding trial, twenty four (24) Saanen lactating does were assigned to four treatment group. The treatments
    were feeding: basal diet only as a control (T1), basal diet with urea molasses multi-nutrient block (UMMB) (T2), basal
    diet with medicated urea molasses multi-nutrient block (MUMB) (T3) and basal diet with commercial mineral block (CMB)
    (T4). There were significant differences (p<0.05) between T2, T3 and T4 on the fecal egg count (FEC). Animals in T2
    and T3 showed moderate level of parasite infestation i.e. at 750 epg and 950 epg, respectively, while animals in T1 and
    T4 showed severe parasite load at 4917 epg and 1850 epg, respectively. There were no significant differences (p>0.05)
    between treatments on WBC, LYM, MON, GRA, RBC, HCT, MCV, MCH, PLT, MPV and PCT. However, significant effects (p<0.05)
    on HBG, MCHC, RDW and PDW were observed in T2 and T3. This research showed that UMMB and MUMB were effective
    in controlling parasite infestation in Saanen lactating dairy goats apart from improving their blood hematological
    parameters. Comparison with CMB showed that it is practical to be used for parasite control.
    Matched MeSH terms: Urea
  11. Cellulose supported promising magnetic sorbents for magnetic solid-phase extraction: A review
    Mhd Haniffa MAC, Ching YC, Illias HA, Munawar K, Ibrahim S, Nguyen DH, et al.
    Carbohydr Polym, 2021 Feb 01;253:117245.
    PMID: 33279000 DOI: 10.1016/j.carbpol.2020.117245
    Cellulose with ample hydroxyl groups is considered as a promising supportive biopolymer for fabricating cellulose supported promising magnetic sorbents (CMS) for magnetic solid-phase extraction (MSPE). The easy recovery via external magnetic field, and recyclability of CMS, associated with different types and surface modifications of cellulose has made them a promising sorbent in the field of solid-phase extraction. CMS based sorbent can offer improved adsorption and absorption capabilities due to its high specific surface area, porous structure, and magnetic attraction feature. This review mainly focuses on the fabrication strategies of CMS using magnetic nanoparticles (MNPs) and various forms of cellulose as a heterogeneous and homogeneous solution either in alkaline mediated urea or Ionic liquids (ILs). Moreover, CMS will be elaborated based on their structures, synthesis, physical performance, and chemical attraction of MNPs and their MSPE in details. The advantages, challenges, and prospects of CMS in future applications are also presented.
    Matched MeSH terms: Urea
  12. Fulltext Urea and creatinine detection on nano-laminated gold thin film using Kretschmann-based surface plasmon resonance biosensor
    Menon PS, Said FA, Mei GS, Berhanuddin DD, Umar AA, Shaari S, et al.
    PLoS One, 2018;13(7):e0201228.
    PMID: 30052647 DOI: 10.1371/journal.pone.0201228
    This work investigates the surface plasmon resonance (SPR) response of 50-nm thick nano-laminated gold film using Kretschmann-based biosensing for detection of urea and creatinine in solution of various concentrations (non-enzymatic samples). Comparison was made with the presence of urease and creatininase enzymes in the urea and creatinine solutions (enzymatic samples), respectively. Angular interrogation technique was applied using optical wavelengths of 670 nm and 785 nm. The biosensor detects the presence of urea and creatinine at concentrations ranging from 50-800 mM for urea samples and 10-200 mM for creatinine samples. The purpose of studying the enzymatic sample was mainly to enhance the sensitivity of the sensor towards urea and creatinine in the samples. Upon exposure to 670 nm optical wavelength, the sensitivity of 1.4°/M was detected in non-enzymatic urea samples and 4°/M in non-enzymatic creatinine samples. On the other hand, sensor sensitivity as high as 16.2°/M in urea-urease samples and 10°/M in creatinine-creatininase samples was detected. The enhanced sensitivity possibly attributed to the increase in refractive index of analyte sensing layer due to urea-urease and creatinine-creatininase coupling activity. This work has successfully proved the design and demonstrated a proof-of-concept experiment using a low-cost and easy fabrication of Kretschmann based nano-laminated gold film SPR biosensor for detection of urea and creatinine using urease and creatininase enzymes.
    Matched MeSH terms: Urea/analysis*; Urease/analysis
  13. Fulltext Dielectric response of nitrogen in soil amended with chicken litter biochar and urea under Oryza sativa L. cultivation
    Maru A, Ahmed OH, Primus WC, Jeffary AV
    Sci Rep, 2021 06 15;11(1):12545.
    PMID: 34131184 DOI: 10.1038/s41598-021-91426-6
    Unbalanced utilization of nitrogen (N) rice not economically viable neither is this practice environmental friendly. Co-application of biochar and urea could reduce the unbalanced use of this N fertilizer in rice cultivation. Thus, a field study was carried out to: (i) determine the effects of chicken litter biochar and urea fertilization on N concentration in soil solution of a cultivated rice (MR219) using dielectric measurement at a low frequency and (ii) correlate soil dielectric conductivity with rice grain yield at maturity. Dielectric response of the soil samples at 20, 40, 55, and 75 days after transplanting were determined using an inductance-capacitance-resistance meter HIOKI 3522-50 LCR HiTESTER. Selected soil chemical properties and yield were determined using standard procedures. The dielectric conductivity and permittivity of the soil samples measured before transplanting the rice seedlings were higher than those for the soil samples after transplanting. This was due to the inherent nitrogen of the chicken litter biochar and the low nitrogen uptake at the transplanting stage. The soil N response increased with increasing measurement frequency and N concentration. The permittivity of the soil samples was inversely proportional to frequency but directly proportional to N concentration in the soil solution. The estimated contents of N in the soil using the dielectric conductivity approach at 1000 Hz decreased with increasing days of fertilization and the results were similar to those of soil NH4+ determined using chemical analysis. The conductivity measured within 1000 Hz and 100,000 Hz correlated positively with the rice grain yield suggesting that nitrogen concentration of the soil can be used to estimate grain yield of the cultivated rice plants.
    Matched MeSH terms: Urea/pharmacology; Urea/chemistry
  14. Fulltext The Cox model of predicting mortality among melioidosis patients in Northern Malaysia: A retrospective study
    Mardhiah K, Wan-Arfah N, Naing NN, Hassan MRA, Chan HK
    Medicine (Baltimore), 2021 Jun 25;100(25):e26160.
    PMID: 34160382 DOI: 10.1097/MD.0000000000026160
    Melioidosis is an infectious disease that is initiated by a bacteria recognized as Burkholderia pseudomallei. Despite the high fatality rate from melioidosis, there is a minimal published study about the disease in Malaysia.This study aimed to identify the prognostic factors of mortality among melioidosis patients in northern Malaysia.All inpatient patients who were admitted to Hospital Sultanah Bahiyah, Kedah and Hospital Tuanku Fauziah, Perlis with culture-confirmed melioidosis during the period 2014 to 2017 were included in the study. The study retrospectively collected 510 melioidosis patients from the Melioidosis Registry. Hazard ratio (HR) used in advanced multiple Cox regression was used to obtain the final model of prognostic factors of melioidosis. The analysis was performed using STATA/SE 14.0 for Windows software.From the results, among the admitted patients, 50.1% died at the hospital. The mean age for those who died was 55 years old, and they were mostly male. The most common underlying disease was diabetes mellitus (69.8%), followed by hypertension (32.7%). The majority of cases (86.8%) were bacteremic. The final Cox model identified 5 prognostic factors of mortality among melioidosis patients. The factors were diabetes mellitus, type of melioidosis, platelet count, white blood cell count, and urea value. The results showed that bacteremic melioidosis increased the risk of dying by 3.47 (HR: 3.47, 95% confidence intervals [CI]: 1.67-7.23, P = .001) compared to non-bacteremic melioidosis. Based on the blood investigations, the adjusted HRs from the final model showed that all 3 blood investigations were included as the prognostic factors for the disease (low platelet: HR = 1.76, 95% CI: 1.22-2.54, P = .003; high white blood cell: HR = 1.49, 95% CI 1.06-2.11, P = .023; high urea: HR = 2.92, 95% CI: 1.76-4.85, P urea: HR = 2.69, 95% CI: 1.69-4.29, P 
    Matched MeSH terms: Urea/blood
  15. Stabilization of Human Serum Albumin against Urea Denaturation by Diazepam and Ketoprofen
    Manoharan P, Wong YH, Tayyab S
    Protein Pept Lett, 2015;22(7):611-7.
    PMID: 25961707
    Stabilizing effect of diazepam and ketoprofen, Sudlow's site II markers on human serum albumin (HSA) against urea denaturation was studied using fluorescence spectroscopy. The two-step, three-state urea transition of HSA was transformed into a single-step, two-state transition with the abolishment of the intermediate state along with a shift of the transition curve towards higher urea concentrations in the presence of diazepam or ketoprofen. Interestingly, a greater shift in the transition curve of HSA was observed in the presence of ketoprofen compared to diazepam. A comparison of the intrinsic fluorescence and three-dimensional fluorescence spectra of HSA and partially-denatured HSAs, obtained in the absence and the presence of diazepam or ketoprofen suggested significant retention of native-like conformation in the partially-denatured states of HSA in the presence of Sudlow's site II markers. Taken together, all these results suggested stabilization of HSA in the presence of diazepam or ketoprofen, being greater in the presence of ketoprofen.
    Matched MeSH terms: Urea/pharmacology*
  16. Lead exposure induces metabolic reprogramming in rat models
    Mani MS, Joshi MB, Shetty RR, DSouza VL, Swathi M, Kabekkodu SP, et al.
    Toxicol Lett, 2020 Dec 15;335:11-27.
    PMID: 32949623 DOI: 10.1016/j.toxlet.2020.09.010
    Lead is a toxin of great public health concern affecting the young and aging population. Several factors such as age, gender, lifestyle, dose, and genetic makeup result in interindividual variations to lead toxicity mainly due to variations in metabolic consequences. Hence, the present study aimed to examine dose-dependent lead-induced systemic changes in metabolism using rat model by administering specific doses of lead such as 10 (low lead; L-Pb), 50 (moderate lead; M-Pb), and 100 mg/kg (high lead; H-Pb) body weight for a period of one month. Biochemical and haematological analysis revealed that H-Pb was associated with low body weight and feed efficiency, low total protein levels (p ≤ 0.05), high blood lead (Pb-B) levels (p ≤ 0.001), low ALAD (δ-aminolevulinate dehydratase) activity (p ≤ 0.0001), high creatinine (p ≤ 0.0001) and blood urea nitrogen (BUN) (p ≤ 0.01) levels, elevated RBC and WBC counts, reduced haemoglobin and blood cell indices compared to control. Spatial learning and memory test revealed that H-Pb exposed animals presented high latency to the target quadrant and escape platform compared to other groups indicating H-Pb alters cognition function in rats. Histopathological changes were observed in liver and kidney as they are the main target organs of lead toxicity. LC-MS analysis further revealed that Butyryl-L-carnitine (p ≤ 0.01) and Ganglioside GD2 (d18:0/20:0) (p ≤ 0.05) levels were significantly reduced in H-Pb group compared to all groups. Further, pathway enrichment analysis revealed abundance and significantly modulated metabolites associated with oxidative stress pathways. The present study is the first in vivo model of dose-dependent lead exposure for serum metabolite profiling.
    Matched MeSH terms: Blood Urea Nitrogen
  17. Molecular structure, second- and third-order nonlinear optical properties and DFT studies of a novel non-centrosymmetric chalcone derivative: (2E)-3-(4-fluorophenyl)-1-(4-{[(1E)-(4-fluorophenyl)methylene]amino}phenyl)prop-2-en-1-one
    Maidur SR, Patil PS, Ekbote A, Chia TS, Quah CK
    Spectrochim Acta A Mol Biomol Spectrosc, 2017 Sep 05;184:342-354.
    PMID: 28528255 DOI: 10.1016/j.saa.2017.05.015
    In the present work, the title chalcone, (2E)-3-(4-fluorophenyl)-1-(4-{[(1E)-(4-fluorophenyl) methylene]amino}phenyl)prop-2-en-1-one (abbreviated as FAMFC), was synthesized and structurally characterized by single-crystal X-ray diffraction. The compound is crystallized in the monoclinic system with non-centrosymmetric space group P21 and hence it satisfies the essential condition for materials to exhibit second-order nonlinear optical properties. The molecular structure was further confirmed by using FT-IR and 1H NMR spectroscopic techniques. The title crystal is transparent in the Vis-NIR region and has a direct band gap. The third-order nonlinear optical properties were investigated in solution (0.01M) by Z-scan technique using a continuous wave (CW) DPSS laser at the wavelength of 532nm. The title chalcone exhibited significant two-photon absorption (β=35.8×10-5cmW-1), negative nonlinear refraction (n2=-0.18×10-8cm2W-1) and optical limiting (OL threshold=2.73kJcm-2) under the CW regime. In support of the experimental results, a comprehensive theoretical study was carried out on the molecule of FAMFC using density functional theory (DFT). The optimized geometries and frontier molecular orbitals were calculated by employing B3LYP/6-31+G level of theory. The optimized molecular structure was confirmed computationally by IR vibrational and 1H NMR spectral analysis. The experimental UV-Vis-NIR spectrum was interpreted using computational chemistry under time-dependent DFT. The static and dynamic NLO properties such as dipole moments (μ), polarizability (α), and first hyperpolarizabilities (β) were computed by using finite field method. The obtained dynamic first hyperpolarizability β(-2ω;ω,ω) at input frequency ω=0.04282a.u. is predicted to be 161 times higher than urea standard. The electronic excitation energies and HOMO-LUMO band gap for FAMFC were also evaluated by DFT. The experimental and theoretical results are in good agreement, and the NLO study suggests that FAMFC molecule can be a potential candidate in the nonlinear optical applications.
    Matched MeSH terms: Urea
  18. Fulltext Solubility enhancement studies on lurasidone hydrochloride using mixed hydrotropy
    Madan JR, Pawar KT, Dua K
    Int J Pharm Investig, 2015 Apr-Jun;5(2):114-20.
    PMID: 25838997 DOI: 10.4103/2230-973X.153390
    Low aqueous solubility is a major problem faced during formulation development of new drug molecules. Lurasidone HCl (LRD) is an antipsychotic agent specially used in the treatments of schizophrenia and is a good example of the problems associated with low aqueous solubility. Lurasidone is practically insoluble in water, has poor bioavailability and slow onset of action and therefore cannot be given in emergency clinical situations like schizophrenia. Hence, purpose of this research was to provide a fast dissolving oral dosage form of Lurasidone. This dosage form can provide quick onset of action by using the concept of mixed hydrotropy. Initially, solubility of LRD was determined individually in nicotinamide, sodium citrate, urea and sodium benzoate at concentration of 10, 20, 30 and 40% w/v solutions using purified water as a solvent. Highest solubility was obtained in 40% sodium benzoate solution. In order to decrease the individual hydrotrope concentration mixed hydrotropic agents were used. Highest solubility was obtained in 15:20:5 ratio of Nicotinamide + sodium benzoate + sodium citrate. This optimized combination was utilized in the preparation of solid dispersions by using distilled water as a solvent. Solid dispersions were evaluated for X-ray diffraction, differential scanning calorimetry and Fourier-transform infrared to show no drug-hydrotropes interaction has occurred. This solid dispersion was compressed to form fast dissolving tablets. Dissolution studies of prepared tablets were done using USP Type II apparatus. The batch L3 tablets show 88% cumulative drug release within 14 min and in vitro dispersion time was 32 min. It was concluded that the concept of mixed hydrotropic solid dispersion is novel, safe and cost-effective technique for enhancing the bioavailability of poorly water-soluble drugs. The miraculous enhancement in solubility and bioavailability of Lurasidone is clear indication of the potential of mixed hydrotropy to be used in future for other poorly water-soluble drugs in which low bioavailability is a major concern.
    Matched MeSH terms: Urea
  19. Fulltext Role of amino acid arginine for broiler production: A review
    M. J. Khatun, T.C. Loh, H.L. Foo, M.K.I. Khan
    Journal of Engineering and Science Research, 2018;2(3):1-6.
    MyJurnal
    Amino acids are known as anabolic factors that are essential for formation of muscle by stimulating protein synthesis while inhibiting proteolysis, and they are significant component for the synthesis of various nitrogenous compounds. There are 20 amino acids are essential to require in cell for formation of body protein of which about 10 amino acids, which cannot be synthesized by the birds are termed essential. Among the essential amino acid arginine one of the essential amino acids for chickens because, like other birds, they are unable to obtain Arginine from endogenous sources due to the absence of most of the enzymes involved in the urea cycle. This amino acid involved in synthesis of proline, hydroxyl proline and polyamines which are essential for connective tissue synthesis as well as increased growth of chicken. Moreover, L-arginine (L-Arg) is effective for reducing fat deposition in broiler. Moreover, it decrease heat stress increase meat quality and increase immune response of broiler. This re-view presents the recent advances in the relevance of the inclusion of excess L-Arginine in broiler ration to growth, fat deposition and immune response in broiler.
    Matched MeSH terms: Urea
  20. Orexin-mediated restoration of hippocampal synaptic potentiation in mice with established cocaine-conditioned place preference
    Lu GL, Lee MT, Chiou LC
    Addict Biol, 2019 11;24(6):1153-1166.
    PMID: 30276922 DOI: 10.1111/adb.12672
    Orexins (also called hypocretins) are implicated in reward and addiction, but little is known about their role(s) in the association between hippocampal synaptic plasticity and drug preference. Previously, we found that exogenous orexin via OX1 and OX2 receptors can impair low frequency stimulation-induced depotentiation, i.e. restoring potentiation of excitatory synaptic transmission (re-potentiation) in mouse hippocampal slices. Here, we found this re-potentiation in hippocampal slices from mice that had acquired conditioned place preference (CPP) to cocaine. Both 10 and 20 mg/kg of cocaine induced similar magnitudes of CPP in mice and re-potentiation in their hippocampal slices, but differed in their susceptibility to TCS1102, a dual (OX1 and OX2 ) orexin receptor antagonist. TCS1102 significantly attenuated CPP and hippocampal re-potentiation induced by cocaine at 10 mg/kg but not at 20 mg/kg. Nonetheless, SCH23390, an antagonist of dopamine D1-like receptors (D1-likeRs), inhibited the effects induced by both doses of cocaine. SKF38393, a D1-likeR-selective agonist, also induced hippocampal re-potentiation in vitro. Interestingly, this effect was attenuated by TCS1102. Conversely, SCH23390 prevented orexin A-induced hippocampal re-potentiation. These results suggest that endogenous orexins are released in mice during cocaine-CPP acquisition, which sustains potentiated hippocampal transmission via OX1 /OX2 receptors and may contribute to the addiction memory of cocaine. This effect of endogenous orexins, however, may be substituted by dopamine that may dominate hippocampal re-potentiation and CPP via D1-likeRs when the reinforcing effect of cocaine is high.
    Matched MeSH terms: Urea/analogs & derivatives
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