MyMedR

Displaying publications 101 - 120 of 189 in total

Abstract:

Sort:

A study on the effects of increment and decrement repeated fed-batch feeding of glucose on the production of poly(3-hydroxybutyrate) [P(3HB)] by a newly engineered Cupriavidus necator NSDG-GG mutant in batch fill-and-draw fermentation

Biglari N, Orita I, Fukui T, Sudesh K

J Biotechnol, 2020 Jan 10;307:77-86.
PMID: 31669355 DOI: 10.1016/j.jbiotec.2019.10.013

This study investigates the effect of strategies on poly(3-hydroxybutyrate) [P(3HB)] production in bioreactor. In the production of P(3HB), urea and glucose feeding streams were developed to characterize the fed-batch culture conditions for new Cupriavidus necator NSDG-GG mutant. Feeding urea in repeated fed-batch stage (RFB-I) at 6, and 12 h in cultivation led to insignificant kinetic effect on the cell dry mass (CDM) and P(3HB) accumulation. Feeding glucose in repeated fed-batch stage (RFB-II) demonstrated that the incremental feeding approach of glucose after urea in fill-and-draw (F/D) mode at 24, 30, 36, 42, and 48 h in fermentation increased CDM and P(3HB) concentration. In the 1st cycle in RFB-II, the cumulative CDM reached the value of 26.22 g/L and then it increased with the successive repeated fed-batches to attain biomass of 145 g/L at the end of 5th cycle of RFB-II. The final cumulative P(3HB) concentration at the end of 5th cycle of RFB-II reached 111 g/L with the overall yield of 0.50 g P(3HB) g gluc- 1; the CDM productivity from the RFB-II cycles was in the range of 0.84-1.3 g/(L·h). The RFB-II of glucose in an increment mode produced nearly 2.2 times more increase in CDM and P(3HB) productivities compared to the decrement RFB-II mode. Repeated cultivation had also the advantage of avoiding extra time required for innoculum preparation, and sterilization of bioreactor during batch, thereby it increased the overall industrial importance of the process.

Matched MeSH terms: Urea
Fulltext Bio-Cementation in Construction Materials: A Review

Iqbal DM, Wong LS, Kong SY

Materials (Basel), 2021 Apr 23;14(9).
PMID: 33922871 DOI: 10.3390/ma14092175

The rapid development of the construction sector has led to massive use of raw construction materials, which are at risk of exhaustion. The problem is aggravated by the high demand for cement as binding powder and the mass production of clay bricks for construction purposes. This scenario has led to high energy consumption and carbon emissions in their production. In this regard, bio-cementation is considered a green solution to building construction, because this technology is environmentally friendly and capable of reducing carbon emissions, thus slowing the global warming rate. Most of the previously published articles have focused on microbiologically induced calcium carbonate precipitation (MICP), with the mechanism of bio-cementation related to the occurrence of urea hydrolysis as a result of the urease enzymatic activity by the microbes that yielded ammonium and carbonate ions. These ions would then react with calcium ions under favorable conditions to precipitate calcium carbonate. MICP was investigated for crack repair and the surface treatment of various types of construction materials. Research on MICP for the production of binders in construction materials has become a recent trend in construction engineering. With the development of cutting edge MICP research, it is beneficial for this article to review the recent trend of MICP in construction engineering, so that a comprehensive understanding on microbial utilization for bio-cementation can be achieved.

Matched MeSH terms: Urea; Urease
Fulltext Hartman's solution or normal saline in the treatment of hyperemesis gravidarum among South East Asian population: a randomised controlled trial

Adibah, I., Khursiah, D., Ahmad, A.I., Zaki, N.N.M.

International Medical Journal Malaysia, 2008;7(2):21-24.
MyJurnal

Introduction: The aim of treatment for hyperemesis gravidarum is to stop vomiting, correction of dehydration, starvation and electrolytes imbalance. The common types of fluid used for fluid replacement are isotonic solutions like normal saline and hartman's solutions. The absence of potassium in normal saline makes hartman's solution superior but there is a possibility that the lactate component in hartman's solution could worsen the starvation state of the patients. This study is to evaluate which of these two solutions is more effective for fluid replacement in hyperemesis gravidarum. The objectives are to compare which solution corrects dehydration, hypokalaemia and acetonuria faster and to evaluate whether the ketosis state is aggravated by lactate component in hartman's solution. Materials and Methods: Patients with hyperemesis gravidarum were randomised to receive either Hartman's solution or normal saline at the rate of 125mls/hour. Blood urea and serum electrolytes, haematocrit, lactate and urine acetone were taken during admission and repeated every 12 hours. The volume of fluid required to correct dehydration, hypokalaemia and acetonuria were compared. Comparison of the pre and post treatment level of serum lactate were also done. Results: Both hartman's solution and normal saline are both effective in correcting dehydration (11.52Â±3.28 pints versus 11.94 Â± 2.30pints respectively) and acetonuria (11.64 Â± 2.75 pints versus 11.64 Â± 2.54 pints respectively).
A lower volume of hartman's solution was needed to correct hypokalaemia (8.34 Â± 2.44 pints versus 8.88 Â± 2.63 pints) but was not statistically significant. Ketonaemia was not made worse after treatment with hartman's solution. Conclusion: Normal saline and hartman's solution are equally effective in treating complications of hyperemesis gravidarum.

Matched MeSH terms: Urea
Fulltext Incidence of Helicobacter pylori Infection using (13) C- Urea BreathTest and Gastric Biopsy Culture

Khairul, A.J., Anwar, A., Ramelah, M.

International Medical Journal Malaysia, 2007;6(2):1-8.
MyJurnal

Background: (13) C – urea breath test (UBT) is sensitive and specific for detection of Helicobacter pylori (H. pylori) infection. Gastric biopsy culture for H. pylori confirms the diagnosis. Here, we analyzed data of all patients who were investigated for H. pylori infection using both tests throughout the year 2005. Materials and Methods : Retrospective data of 377 patients between the ages of 17 – 88 were identified through endoscopy records from January to December 2005. Upper endoscopy, UBT and gastric biopsy culture were performed on all patients simultaneously during each endoscopy session. Patients who had positive UBT and biopsy culture for H. pylori were treated with triple therapy of PPI, amoxicillin and clarithromycin for one week. A repeat of UBT was done at one-month post therapy. Results and Analysis: Twenty-eight patients on the list had no available data on UBT and were omitted from the analysis. Ethnic group Chinese comprised of 45.4% (n=163), followed by Malay, 37.3% (n=134), Indian, 10.6% (n=38) and others, 3.9% (n=14). UBT was positive in 23.7% (n=85)(figure1). H. pylori culture was positive in 19.2% (n=69)(figure1). Sixteen patients with UBT positive had H. pylori culture negative, 18.8% (n=16/85)(figure2). Five patients with H. pylori culture positive had UBT negative, 7.2% (n=5/69)(figure3). Ethnic group Indian had the highest incidence of UBT positive, 47.4% (n=18/38), followed by Others (Sikhs and foreigners) 42.8% (n=6/14), the Chinese 27.6% (n=45/163) and the Malays 11.6% (n= 16/138). UBT positive was the highest in the age group of 50 and above, 64.7% (n=55/85), followed by the age group between 30 to 49, 21.2% (n=18/85) and the age group of 29 and below, 14.5% (n=12/85). Out of the 85 UBT positive patients 91.8% (n=78/85)(figure4) of them responded to the conventional one week of triple therapy (PPI, amoxicillin, clarithromycin) with negative UBT at one-month post therapy compared to only 8.2% (n=7/85)(figure4) who failed with positive UBT at one-month post therapy.

Matched MeSH terms: Urea
Fulltext Influence of nitrogen source on the growth and biochemical composition of an antarctic chlorella

Chu, W.L., Phang, S.M., Lim, S.L., Teoh, M.L., Wong, C.Y.

ASM Science Journal, 2009;3(2):178-183.
MyJurnal

Chlorella is one of the common microalgae found in a wide range of habitats, including Antarctica. Chlorella UMACC 234 is an interesting isolate in the collection of Antarctic microalgae in the University of Malaya algae culture collection (UMACC) as it grows well at temperatures much higher than the ambience. The alga was isolated from snow samples collected from Casey, Antarctica. This study investigates the influence of nitrogen source on the growth, biochemical composition and fatty acid profile of Chlorella UMACC 234. The cultures were grown in Bold’s Basal Medium with 3.0 mM NaNO3, NH4Cl or urea. The cultures grown on NaNO3 attained the highest specific growth rate (μ = 0.43 day–1) while the specific growth rates of those grown on NH4Cl and urea were not significantly different (p > 0.05). The urea-grown cells produced the highest amounts of lipids (25.7% dry weight) and proteins (52.5% dry weight) compared to those grown on other nitrogen sources. The cell numbers attained by the cultures grown at NaNO3 levels between 0.3 and 3.0 mM were similar but decreased markedly at 9.0 mM NaNO3. The fatty acids of Chlorella UMACC 234 were dominated by saturated fatty acids, especially 16:0 and 18:0. The percentage of polyunsaturated fatty acids was very low, especially in cells grown on urea (0.9% total fatty acids). Characterisation of the growth and biochemical composition of this Antarctic Chlorella is important to our studies on the relationship of Chorella isolates from tropical, temperate and polar regions, especially in terms of phylogeny and stress adaptation.

Matched MeSH terms: Urea
Fulltext Kinetic modeling of bacteriocin-like inhibitory substance secretion by Pediococcus acidilactici Kp10 and its stability in food manufacturing conditions

Abbasiliasi S, Tan JS, Ibrahim TAT, Ramanan RN, Kadkhodaei S, Mustafa S, et al.

J Food Sci Technol, 2018 Apr;55(4):1270-1284.
PMID: 29606741 DOI: 10.1007/s13197-018-3037-x

This paper deliberates the modelling and validation of bacteriocin-like inhibitory substance (BLIS) secretion by Pediococcus acidilactici Kp10 at different agitation speeds in a stirred tank bioreactor. A range of models namely the re-parameterised logistic, Luedeking-Piret and maintenance energy were assessed to predict the culture performance of the said bacterium. Growth of P. acidilactici Kp10 was enhanced with increased agitation speed up to 600 rpm while BLIS secretion was maximum at 400 rpm but decreased at higher agitation speed. Growth of P. acidilactici aptly subscribed to the re-parameterised logistic model while BLIS secretion and lactose consumption fitted well with the Luedeking-Piret model. The models revealed a relationship between growth of the bacterium and BLIS secretion. Bacterial growth and BLIS secretion were largely affected by the agitation speed of the stirred tank bioreactor which regulated the oxygen transfer to the culture. BLIS secretion by P. acidilactici Kp10 was however enhanced in oxygen-limited culture. The study also assessed BLIS from the perspective of its stability when subjected to factors such as temperature, pH and detergents. Results showed that BLIS produced by this strain was not affected by heat (at 25-100 °C for 20 min and at 121 °C for 15 min), surfactant (Tween 40, 60 and 80 and urea), detergents (up to 1% SDS), organic solvents (50% each of acetone, methanol and ethanol) and stable in a wide range of pH (2-10). The above information are pertinent with reference to commercial applications of this bacterial product in food manufacturing which invariably involve various sterilization processes and subjected to a wide pH range.

Matched MeSH terms: Urea
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
Fulltext Statistical investigation of extraction parameters of keratin from chicken feather using Design-Expert

Kamarudin NB, Sharma S, Gupta A, Kee CG, Chik SMSBT, Gupta R

3 Biotech, 2017 Jun;7(2):127.
PMID: 28573397 DOI: 10.1007/s13205-017-0767-9

Uncontrolled disposal of feathers from the poultry industry and slaughterhouses is environmentally undesirable. The feathers are composed of approximately 90% of keratin which is an important ingredient of cosmetics, shampoos and hair treatment creams. This study aimed to determine the optimum conditions for the extraction of keratin from chicken feathers. The extraction of keratin using various reducing agents was studied using statistical experimental design. In the extraction process, pH, temperature, ratio of reducing agents, mass of chicken feathers and incubation time were analyzed. The keratin in the total extracted protein was purified by size exclusion chromatography, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and further characterized using amino acids profile analysis. The surface morphology and chemical composition were studied by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis. Sodium sulfide (Na2S) yielded 84.5% of keratin as compared to sodium hydroxide (43.8), urea mixture (50.6), mixture of sodium dodecyl sulfate (SDS) and sodium bisulfite (18.3) and a mixture of Na2S and sodium hydroxide (41.5%) under optimized conditions. The optimum yield of keratin was achieved at 80.9 °C in 9.5 h with 0.05 M sodium sulfide using response surface methodology (RSM). Among the five parameters screened, pH was found not to be significant because the p value was greater than 0.05.

Matched MeSH terms: Urea
Fulltext Protein improvement of banana peel through sequential solid state fermentation using mixed-culture of Phanerochaete chrysosporium and Candida utilis

Olorunnisola KS, Jamal P, Alam MZ

3 Biotech, 2018 Oct;8(10):416.
PMID: 30237963 DOI: 10.1007/s13205-018-1435-4

Banana peel (BP) is a major waste produced by fruit processing industries. Pre-treatment of BP at different temperatures led to 40% reduction in saponin at 100 °C (from 9.5 to 5.7 mg/g). Sequential mixed culture of Phanerochaete chrysosporium (P. chrysosporium) and Candida utilis (C. utilis) gave highest protein enrichment (88.93 mg/g). There is 26% increase in protein synthesis (from 88.93 to 111.78 mg/g) after media screening. Inclusion of KH2PO4, FeSO4·7H2O, wheat flour and sucrose in the media contributed positively to protein synthesis, while elevated concentration of urea, peptone, K2HPO4, KCl, NH4H2PO4, and MgSO4.7H2O are required to reach optimum protein synthesis. Total soluble sugar (TSS), total reducing sugar (TRS) and total carbohydrate (CHO) consumption varied with respect to protein synthesis in all experimental runs. Optimum protein synthesis required 6 days and inclusion of 5% sucrose, 0.6% NH4H2PO4, 0.4% KCl, and 0.5% MgSO4·7H2O as concentration media constituents to reach 140.95 mg/g protein synthesis equivalent to 300% increase over the raw banana peel protein content (35.0 mg/g).

Matched MeSH terms: Urea
Fulltext Enhancement of bioplastic polyhydroxybutyrate P(3HB) production from glucose by newly engineered strain Cupriavidus necator NSDG-GG using response surface methodology

Biglari N, Ganjali Dashti M, Abdeshahian P, Orita I, Fukui T, Sudesh K

3 Biotech, 2018 Aug;8(8):330.
PMID: 30073115 DOI: 10.1007/s13205-018-1351-7

This study aimed to enhance production of polyhydroxybutyrate P(3HB) by a newly engineered strain of Cupriavidus necator NSDG-GG by applying response surface methodology (RSM). From initial experiment of one-factor-at-a-time (OFAT), glucose and urea were found to be the most significant substrates as carbon and nitrogen sources, respectively, for the production of P(3HB). OFAT experiment results showed that the maximum biomass, P(3HB) content, and P(3HB) concentration of 8.95 g/L, 76 wt%, and 6.80 g/L were achieved at 25 g/L glucose and 0.54 g/L urea with an agitation rate of 200 rpm at 30 °C after 48 h. In this study, RSM was applied to optimize the three key variables (glucose concentration, urea concentration, and agitation speed) at a time to obtain optimal conditions in a multivariable system. Fermentation experiments were conducted in shaking flask by cultivation of C. necator NSDG-GG using various glucose concentrations (10-50 g/L), urea concentrations (0.27-0.73 g/L), and agitation speeds (150-250 rpm). The interaction between the variables studied was analyzed by ANOVA analysis. The RSM results indicated that the optimum cultivation conditions were 37.70 g/L glucose, 0.73 g/L urea, and 200 rpm agitation speed. The validation experiments under optimum conditions produced the highest biomass of 12.84 g/L, P(3HB) content of 92.16 wt%, and P(3HB) concentration of 11.83 g/L. RSM was found to be an efficient method in enhancing the production of biomass, P(3HB) content, and P(3HB) concentration by 43, 21, and 74%, respectively.

Matched MeSH terms: Urea
Fulltext Effects of Corn Supplementation into PKC-Urea Treated Rice Straw Basal Diet on Hematological, Biochemical Indices and Serum Mineral Level in Lambs

Saeed OA, Sazili AQ, Akit H, Alimon AR, Samsudin AA

Animals (Basel), 2019 Oct 11;9(10).
PMID: 31614434 DOI: 10.3390/ani9100781

Twenty-seven Dorper lambs were used to determine the effect of supplementing corn as a source of energy into the palm kernel cake (PKC) urea-treated rice straw basal diet on the blood metabolic profile and metals in lambs. The lambs were randomly allotted to three experimental treatments according to their initial body weight for a 120 day trial. Dietary treatments were: T1 (control diet) = 75.3% of PKC + 0% corn, T2 = 70.3% of PKC + 5% corn, and T3 = 65.3% of PKC + 10% corn. The results of this study indicated that copper (Cu), selenium (Se), zinc (Zn), and iron (Fe) concentration intake, retention, and its absorption from the gut and apparent mineral digestibility were highly significant for the levels of corn supplementation. The biochemical and hematological parameters remained within normal levels with the treatments, but the white blood cell, eosinophil count, cholesterol, and low-density lipoprotein cholesterol (LDL) were significantly higher in T3. Treatment 3 significantly increased the concentration of Se and Fe, while Zn was reduced in the blood serum of lambs on day 120. The result shows that the inclusion of corn has no effect on the hematological and biochemical parameters of lambs after incorporating corn into the PKC-based diet at 5% and 10%.

Matched MeSH terms: Urea
Comparison of deep eutectic solvents (DES) on pretreatment of oil palm empty fruit bunch (OPEFB): Cellulose digestibility, structural and morphology changes

Thi S, Lee KM

Bioresour Technol, 2019 Jun;282:525-529.
PMID: 30898410 DOI: 10.1016/j.biortech.2019.03.065

In this work, a novel solvent, deep eutectic solvent (DES) was applied to examine its effectiveness in pretreating OPEFB. Three types of DESs, i.e. choline chloride-lactic acid (ChCl-LA), choline chloride-urea (ChCl-U) and choline chloride-glycerol (ChCl-G) were investigated. The pretreatment performance was based on cellulose digestibility, structural and morphology changes. At molar ratio of 1:2, ChCl-LA attained the highest reducing sugars yield of 20.7%, followed by ChCl-G (20.0%) and ChCl-U (16.9%). FT-IR and SEM results further confirmed the outstanding ability of ChCl-LA due of its ability in cellulose, hemicellulose and lignin disruption, exposing its cellulose fraction to enzymatic hydrolysis. ChCl-LA is also more favorable compare to acid and alkaline solvents as it could prevent sugars loss, use of expensive corrosion resistant equipment and ease products separation.

Matched MeSH terms: Urea
Fulltext Nitrogen Pollution Impact and Remediation through Low Cost Starch Based Biodegradable polymers

Ibrahim KA, Naz MY, Shukrullah S, Sulaiman SA, Ghaffar A, AbdEl-Salam NM

Sci Rep, 2020 Apr 03;10(1):5927.
PMID: 32246028 DOI: 10.1038/s41598-020-62793-3

The world does not have too much time to ensure that the fast-growing population has enough land, food, water and energy. The rising food demand has brought a positive surge in fertilizers' demand and agriculture-based economy. The world is using 170 million tons of fertilizer every year for food, fuel, fiber, and feed. The nitrogenous fertilizers are being used to meet 48% of the total food demand of the world. High fertilizer inputs augment the reactive nitrogen levels in soil, air, and water. The unassimilated reactive nitrogen changes into a pollutant and harms the natural resources. The use of controlled-release fertilizers for slowing down the nutrients' leaching has recently been practiced by farmers. However, to date, monitoring of the complete discharge time and discharge rate of controlled released fertilizers is not completely understood by the researchers. In this work, corn starch was thermally processed into a week gel-like coating material by reacting with urea and borate. The granular urea was coated with native and processed starch in a fluidized bed reactor having bottom-up fluid delivery system. The processed starch exhibited better thermal and mechanical stability as compared to the native starch. Unlike the pure starch, the storage modulus of the processed starch dominated the loss modulus. The release time of urea, coated with processed starch, remained remarkably larger than the uncoated urea.

Matched MeSH terms: Urea
Effects of different doses of fertilizers on growth and yield components of biodiesel plant (jatropha curcas l.)

Inam Ali Shah, Sultan Mehmod Wazir, Rahmat Ali Khan

Sains Malaysiana, 2017;46:117-122.

Effects of different doses of fertilizers on growth and yield components of biodiesel plant (Jatropha curcas L.), was
made in the prevailing environment of University of Science and Technology Bannu. The experiment was carried out in
randomized complete block design (RCBD) with three replications. Nitrogen, phosphorus and potassium were applied
in the form of urea, single super phosphate and potash in the shape of combined NPK, respectively, during sprouting
of leaves and thereafter with each irrigation in split doses. The analysis of variance for number of branches per plant
showed significant results indicated in ANOVA. Significantly the number of primary branches per plant 8.07 was recorded
in T4 with the application of dose of (N P K: 2507.5 gm: 1091.5 gm: 501.5 gm). Maximum No. of secondary branches
per plant (9.100) were recorded in T1 especially at both plots. Flower per inflorescence showed that maximum value
(122.810) was recorded in T5 of especially at both plots. Inflorescence plant-1 showed that maximum value (39.477) were
recorded in T1 and minimum value were noted as (12.733) at T3 on both the flats. The data for fruits per plant showed
that maximum value (143.300) was recorded in T1. The seed index, which was the output of the aim of this research work,
reflects highly significant differences in mean value observed for both subplots. Mean values showed that maximum seeds
weight 45.86 was recorded in T1 of especially at both plots while low seed index was noted as 22.84 at T5 (N: 3400 gm,
P: 1480 gm, K: 680 gm) at both the subplots.

Matched MeSH terms: Urea
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
Fulltext Inclusion of 2-Mercaptoethanol in Lysis Buffer Could Interfere with Isolation of High Molecular Weight DNA from Freshwater Microalgae

Yee W, Kumar JN, Muthusamy PD

Indian J Microbiol, 2018 Mar;58(1):109-113.
PMID: 29434405 DOI: 10.1007/s12088-017-0698-5

2-mercaptoethanol (2-ME), alongside polyvinylpyrrolidone is commonly used in plant DNA extractions to deal with polyphenols, which could interfere with extraction and downstream applications. 2-ME is also commonly used to denature proteins and nucleases, especially RNAses. On the contrary, we found that the presence of 2-ME in lysis buffer interfered with DNA extraction from 12 strains of freshwater microalgae, resulting in DNA with poor integrity. We also found that the TNES-urea buffer, commonly used for preservation and DNA extraction from fish, appears as effective as the SDS and CTAB buffer for some microalgae strains. Results from our study suggests that the inclusion of 2-ME in DNA extraction protocols may be detrimental for isolation of good quality DNA from freshwater microalgae, and therefore recommend eliminating it or testing varying concentrations of 2-ME when developing species-specific extraction protocols for microalgae.

Matched MeSH terms: Urea
Fulltext Effects of Quercetin on Tubular Cell Apoptosis and Kidney Damage in Rats Induced by Titanium Dioxide Nanoparticles

Alidadi H, Khorsandi L, Shirani M

Malays J Med Sci, 2018 Mar;25(2):72-81.
PMID: 30918457 DOI: 10.21315/mjms2018.25.2.8

Background: Recent studies have demonstrated that many nanoparticles have an adverse or toxic effect on the kidney.
Objective: To investigate the nephroprotective effect of quercetin (QT) against renal injury induced by titanium dioxide nanoparticles (NTiO2) in rats.
Methods: NTiO2-intoxicated rats received 50 mg/kg of NTiO2 for seven days. The QT + NTiO2 group was pretreated with QT for seven days before being administered NTiO2. Uric acid, creatinine, and blood urea nitrogen were considered to be biomarkers of nephrotoxicity. Catalase (CAT) and superoxide dismutase (SOD) activities and renal levels of malondialdehyde (MDA) were measured to assess the oxidative stress caused by NTiO2.
Results: NTiO2 significantly increased the plasma level of the biomarkers. It also significantly decreased the activities of CAT (P = 0.008) and SOD (P = 0.004), and significantly increased the MDA levels (P = 0.007). NTiO2 caused proximal tubule damage, the accumulation of red blood cells, the infiltration of inflammatory cells, and reduced the glomerular diameters, as well as induced apoptosis in the proximal tubules. Pre-treatment with QT attenuated the histological changes, normalised the plasma biomarkers, suppressed oxidative stress, ameliorated the activities of CAT (P = 0.007) and SOD (P = 0.006), and reduced apoptosis (P < 0.001).
Conclusion: QT was found to have a potent protective effect against nephrotoxicity induced by NTiO2 in rats. It also reduced apoptosis caused by NTiO2.

Matched MeSH terms: Blood Urea Nitrogen
Correlation of tumour response with starting tumour size and dose of tamoxifen in an N-methyl-N-nitrosourea (NMU)-induced rat mammary cancer model

Yankuzo HM, Emilia ST, Shaari R, Yaacob NS

Asian Pac J Cancer Prev, 2014;15(16):6721-6.
PMID: 25169515

BACKGROUND: The aim of this preliminary study was to address variations of responses observed with different starting tumor sizes of 10 and 15 mm, and the effects of different doses of tamoxifen (TAM) on experimental rat mammary tumors.
MATERIALS AND METHODS: Thirty-five inbred female Sprague Dawley rats aged 43 days were administered with three weekly doses of N-methyl-N-nitrosourea (NMU) intraperitoneally (ip) at 50 mg/kg body weight. Animals were randomized (beginning from 10 mm tumor size) into four TAM-treated (50, 100, 200 and 500 μg/day) groups of six animals each, and another group (n=6) treated with TAM 100 μg/day at starting tumour size of 15 mm. The animals were treated by oral gavage daily for 8 weeks before sacrifice.
RESULTS: Serum urea and creatinine, and overall physical tumor burden were significantly modulated in animals treated with variable doses of TAM compared to the untreated controls (n=5). Final body weight and tumor number were significantly different in the 10 mm-treated animals compared to those treated at 15 mm. There were no significant differences in histopathological features among all the groups.
CONCLUSIONS: Our findings suggest the importance of standardizing tumour size and drug doses before initiation of treatment, particularly in the direct comparison of basic end-tumour physical parameters.

Matched MeSH terms: Methylnitrosourea; Urea/blood
Impact of serum acetaminophen concentration on changes in serum potassium, creatinine and urea concentrations among patients with acetaminophen overdose

Zyoud SH, Awang R, Sulaiman SA, Al-Jabi SW

Pharmacoepidemiol Drug Saf, 2011 Feb;20(2):203-8.
PMID: 21254292 DOI: 10.1002/pds.2060

Acetaminophen overdose may be accompanied by electrolyte disturbances. The basis for electrolyte change appears to be due to increased fractional urinary electrolyte excretion.

Matched MeSH terms: Urea/blood*
Nitrogen metabolism and excretion in the aquatic chinese soft-shelled turtle, Pelodiscus sinensis, exposed to a progressive increase in ambient salinity

Lee SM, Wong WP, Hiong KC, Loong AM, Chew SF, Ip YK

J. Exp. Zoolog. Part A Comp. Exp. Biol., 2006 Dec 1;305(12):995-1009.
PMID: 17068799

This study aimed to determine effects of 6-day progressive increase in salinity from 1 per thousand to 15 per thousand on nitrogen metabolism and excretion in the soft-shelled turtle, Pelodiscus sinensis. For turtles exposed to 15 per thousand water on day 6, the plasma osmolality and concentrations of Na+, Cl- and urea increased significantly, which presumably decreased the osmotic loss of water. Simultaneously, there were significant increases in contents of urea, certain free amino acids (FAAs) and water-soluble proteins that were involved in cell volume regulation in various tissues. There was an apparent increase in proteolysis, releasing FAAs as osmolytes. In addition, there might be an increase in catabolism of certain amino acids, producing more ammonia. The excess ammonia was retained as indicated by a significant decrease in the rate of ammonia excretion on day 4 in 15 per thousand water, and a major portion of it was converted to urea. The rate of urea synthesis increased 1.4-fold during the 6-day period, although the capacity of the hepatic ornithine urea cycle remained unchanged. Urea was retained for osmoregulation because there was a significant decrease in urea excretion on day 4. Increased protein degradation and urea synthesis implies greater metabolic demands, and indeed turtles exposed to 15 per thousand water had significantly higher O2 consumption rate than the freshwater (FW) control. When turtles were returned from 15 per thousand water to FW on day 7, there were significant increases in ammonia (probably released through increased amino acid catabolism) and urea excretion, confirming that FAAs and urea were retained for osmoregulatory purposes in brackish water.

Matched MeSH terms: Urea/metabolism

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links