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Diallyl sulphide, a component of garlic, abrogates ferric nitrilotriacetate-induced oxidative stress and renal damage in rats

Ansar S, Iqbal M, AlJameil N

Hum Exp Toxicol, 2014 Dec;33(12):1209-16.
PMID: 24596035 DOI: 10.1177/0960327114524237

Ferric nitrilotriacetate (Fe-NTA) induces tissue necrosis as a result of lipid peroxidation (LPO) and oxidative damage that leads to high incidence of renal carcinomas. The present study was undertaken to evaluate the effect of diallyl sulphide (DAS) against Fe-NTA-induced nephrotoxicity. A total of 30 healthy male rats were randomly divided into 5 groups of 6 rats each: (1) control, (2) DAS (200 mg kg(-1)), (3) Fe-NTA (9 g Fe kg(-1)), (4) DAS (100 mg kg(-1)) + Fe-NTA (9 mg Fe kg(-1)) and (5) DAS (200 mg kg(-1)) + Fe-NTA (9 mg Fe kg(-1)). Fe-NTA + DAS-treated groups were given DAS for a period of 1 week before Fe-NTA administration. The intraperitoneal administration of Fe-NTA enhanced blood urea nitrogen and creatinine levels with reduction in levels of antioxidant enzymes. However, significant restoration of depleted renal glutathione and its dependent enzymes (glutathione reductase and glutathione-S-transferase) was observed in DAS pretreated groups. DAS also attenuated Fe-NTA-induced increase in LPO, hydrogen peroxide generation and protein carbonyl formation (p < 0.05). The results indicate that DAS may be beneficial in ameliorating the Fe-NTA-induced renal oxidative damage in rats.

Matched MeSH terms: Blood Urea Nitrogen
Fulltext Toxicity Evaluation of the Naphthalen-2-yl 3,5-Dinitrobenzoate: A Drug Candidate for Alzheimer Disease

Anwar F, Saleem U, Rehman AU, Ahmad B, Froeyen M, Mirza MU, et al.

Front Pharmacol, 2021;12:607026.
PMID: 34040515 DOI: 10.3389/fphar.2021.607026

The presented study was designed to probe the toxicity potential of newly identified compound naphthalen-2-yl 3,5-dinitrobenzoate (SF1). Acute, subacute toxicity and teratogenicity studies were performed as per Organization of economic cooperation and development (OECD) 425, 407, and 414 test guidelines, respectively. An oral dose of 2000 mg/kg to rats for acute toxicity. Furthermore, 5, 10, 20, and 40 mg/kg doses were administered once daily for 28 days in subacute toxicity study. Teratogenicity study was performed with 40 mg/kg due to its excellent anti-Alzheimer results at this dose. SF1 induced a significant rise in Alkaline Phosphatases (ALP), bilirubin, white blood cells (WBC), and lymphocyte levels with a decrease in platelet count. Furthermore, the reduction in urea, uric acid, and aspartate transaminase (AST) levels and an increase in total protein levels were measured in subacute toxicity. SF1 increased spermatogenesis at 5 and 10 mg/kg doses. Teratogenicity study depicted no resorptions, early abortions, cleft palate, spina bifida and any skeletal abnormalities in the fetuses. Oxidative stress markers (Superoxide dismutase (SOD), Catalase (CAT), and glutathione (GSH) were increased in all the experiments, whereas the effect on melanoaldehyde Malondialdehyde (MDA) levels was variable. Histopathology further corroborated these results with no change in the architectures of selected organs. Consequently, a 2000 mg/kg dose of SF1 tends to induce minor liver dysfunction along with immunomodulation, and it is well below its LD
50
. Moreover, it can be safely used in pregnancy owing to its no detectable teratogenicity.

Matched MeSH terms: Urea
N-doped TiO2 synthesised via microwave induced photocatalytic on RR4 dye removal under LED light irradiation

Azami MS, Nawawi WI, Ali H. Jawad, Ishak MAM, Azami MS, K. Ismail

Sains Malaysiana, 2017;46:1390-1316.

Nitrogen doped titanium dioxide (N-doped TiO2
) was synthesized by microwave using urea as nitrogen sources with
commercially available TiO2
-P25. The N-doped TiO2
was compared with unmodified TiO2
by carrying out the investigation
on its properties using x-ray diffraction (XRD) analysis, Brunauer-Emmett-Teller (BET), Fourier transformed infrared
spectroscopy (FTIR) and diffuse reflectance spectroscopy (UV-Vis DRS). The photocatalytic activities of N-doped TiO2
and unmodified TiO2 were studied for photodegradation of reactive red 4 (RR4) under light emitting diode (LED) light
irradiation. An active photoresponse under LED light irradiation was observed from N-doped TiO2
with 60 min of time
irradiation to complete RR4 color removal while no photocatalytic degradation was observed from unmodified.

Matched MeSH terms: Urea
Review on materials & methods to produce controlled release coated urea fertilizer

Azeem B, KuShaari K, Man ZB, Basit A, Thanh TH

J Control Release, 2014 May 10;181:11-21.
PMID: 24593892 DOI: 10.1016/j.jconrel.2014.02.020

With the exponential growth of the global population, the agricultural sector is bound to use ever larger quantities of fertilizers to augment the food supply, which consequently increases food production costs. Urea, when applied to crops is vulnerable to losses from volatilization and leaching. Current methods also reduce nitrogen use efficiency (NUE) by plants which limits crop yields and, moreover, contributes towards environmental pollution in terms of hazardous gaseous emissions and water eutrophication. An approach that offsets this pollution while also enhancing NUE is the use of controlled release urea (CRU) for which several methods and materials have been reported. The physical intromission of urea granules in an appropriate coating material is one such technique that produces controlled release coated urea (CRCU). The development of CRCU is a green technology that not only reduces nitrogen loss caused by volatilization and leaching, but also alters the kinetics of nitrogen release, which, in turn, provides nutrients to plants at a pace that is more compatible with their metabolic needs. This review covers the research quantum regarding the physical coating of original urea granules. Special emphasis is placed on the latest coating methods as well as release experiments and mechanisms with an integrated critical analyses followed by suggestions for future research.

Matched MeSH terms: Urea/chemistry*
Fenofibrate and dipyridamole treatments in low-doses either alone or in combination blunted the development of nephropathy in diabetic rats

Balakumar P, Varatharajan R, Nyo YH, Renushia R, Raaginey D, Oh AN, et al.

Pharmacol Res, 2014 Dec;90:36-47.
PMID: 25263930 DOI: 10.1016/j.phrs.2014.08.008

Low-doses of fenofibrate and dipyridamole have pleiotropic renoprotective actions in diabetic rats. This study investigated their combined effect relative to their individual treatments and lisinopril in rats with diabetic nephropathy. Streptozotocin (55mg/kg, i.p., once)-administered diabetic rats were allowed for 10 weeks to develop nephropathy. Diabetic rats after 10 weeks developed nephropathy with discernible renal structural and functional changes as assessed in terms of increase in kidney weight to body weight ratio (KW/BW), and elevations of serum creatinine, urea and uric acid, which accompanied with elevated serum triglycerides and decreased high-density lipoproteins. Hematoxylin-eosin, periodic acid Schiff and Masson trichrome staining confirmed renal pathological changes in diabetic rats that included glomerular capsular wall distortion, mesangial cell expansion, glomerular microvascular condensation, tubular damage and degeneration and fibrosis. Low-dose fenofibrate (30mg/kg, p.o., 4 weeks) and low-dose dipyridamole (20mg/kg, p.o., 4 weeks) treatment either alone or in combination considerably reduced renal structural and functional abnormalities in diabetic rats, but without affecting the elevated glucose level. Fenofibrate, but not dipyridamole, significantly prevented the lipid alteration and importantly the uric acid elevation in diabetic rats. Lisinopril (5mg/kg, p.o., 4 weeks, reference compound), prevented the hyperglycemia, lipid alteration and development of diabetic nephropathy. Lipid alteration and uric acid elevation, besides hyperglycemia, could play key roles in the development of nephropathy. Low-doses of fenofibrate and dipyridamole treatment either alone or in combination markedly prevented the diabetes-induced nephropathy. Their combination was as effective as to their individual treatment, but not superior in preventing the development of diabetic nephropathy.

Matched MeSH terms: Urea/blood
Achieving dialysis adequacy: A global perspective

Bharati J, Jha V

Semin Dial, 2020 11;33(6):490-498.
PMID: 33030777 DOI: 10.1111/sdi.12924

Dialysis adequacy is conventionally quantified as net urea clearance. Single pool (sp) Kt/Vurea remains the best studied measure of dialysis adequacy globally. Other measures such as fluid status control, anemia correction, and mineral metabolism are monitored variably. Increasing use of hemodiafiltration across Europe and many parts of Japan and Australia is predicated on studies showing better patient survival with middle molecule clearance. Apart from local clinical practice guidelines, the income level and public health policy of a country determine quality of dialysis services. Among developed nations, small solute clearance adequacy targets are achieved with high frequency. In the United States, dialysis adequacy target is met by focussing on high blood flow rates and large dialyzer size, sometimes at the cost of session time. In Japan, Australia, and Germany, session length is given importance. Dialysis adequacy reporting is restricted and inconsistent in developing nations. The Gulf Cooperation Council countries, Russia and Malaysia, respectively, are close to achieving dialysis adequacy target (spKt/Vurea ≥1.2) universally in their dialysis populations. Patient-reported outcomes are typically measured only in developed countries. Patient survival on dialysis, partly linked to dialysis adequacy, varies greatly around the world, with Japan having the best survival rates. Until the development of better markers of dialysis adequacy, universal consistency in reporting of conventional parameters with a focus on patient-reported measures should be endeavored.

Matched MeSH terms: Blood Urea Nitrogen; Urea
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 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
Azostix: a rapid test for blood urea

Buttery JE, de Witt GF, Ahmad UO

Med J Malaya, 1969 Jun;23(4):265-8.
PMID: 4242173
Matched MeSH terms: Blood Urea Nitrogen*
Co-Electrolysis-Assisted Decomposition of Hydroxylammonium Nitrate-Fuel Mixtures Using Stainless Steel-Platinum Electrodes

Chai WS, Sun D, Cheah KH, Li G, Meng H

ACS Omega, 2020 Aug 11;5(31):19525-19532.
PMID: 32803046 DOI: 10.1021/acsomega.0c01804

Hydroxylammonium nitrate (HAN) is a promising green propellant because of its low toxicity, high volumetric specific impulse, and reduced development cost. Electrolytic decomposition of HAN is an efficient approach to prepare it for further ignition and combustion. This paper describes the investigation of a co-electrolysis effect on electrolytic decomposition of HAN-fuel mixtures using stainless steel-platinum (SS-Pt) electrodes. For the first time, different materials were utilized as electrodes to alter the cathodic reaction, which eliminated the inhibition effect and achieved a repeatable and consistent electrolytic decomposition of HAN solution. Urea and methanol were added as fuel components in the HAN-fuel mixtures. When the mass ratio of added urea ≥20%, the electrolytic decomposition of a HAN-urea ternary mixture achieved 67% increment in maximum gas temperature (Tgmax) and 185% increment in overall temperature increasing rate over the benchmark case of HAN solution. The co-electrolysis of urea released additional electrons into the mixtures and enhanced the overall electrolytic decomposition of HAN. In contrast, the addition of methanol did not improve the Tgmax but only increased the overall temperature increasing rate. This work has important implications in the development of an efficient and reliable electrolytic decomposition system of HAN and its mixtures for propulsion applications.

Matched MeSH terms: Urea
Fulltext Evaluation of the geographical utility of Eastern Russell's viper (Daboia siamensis) antivenom from Thailand and an assessment of its protective effects against venom-induced nephrotoxicity

Chaisakul J, Alsolaiss J, Charoenpitakchai M, Wiwatwarayos K, Sookprasert N, Harrison RA, et al.

PLoS Negl Trop Dis, 2019 10;13(10):e0007338.
PMID: 31644526 DOI: 10.1371/journal.pntd.0007338

BACKGROUND: Daboia siamensis (Eastern Russell's viper) is a medically important snake species found widely distributed across Southeast Asia. Envenomings by this species can result in systemic coagulopathy, local tissue injury and/or renal failure. While administration of specific antivenom is an effective treatment for Russell's viper envenomings, the availability of, and access to, geographically-appropriate antivenom remains problematic in many rural areas. In this study, we determined the binding and neutralizing capability of antivenoms manufactured by the Thai Red Cross in Thailand against D. siamensis venoms from four geographical locales: Myanmar, Taiwan, China and Thailand.
METHODOLOGY/PRINCIPLE FINDINGS: The D. siamensis monovalent antivenom displayed extensive recognition and binding to proteins found in D. siamensis venom, irrespective of the geographical origin of those venoms. Similar immunological characteristics were observed with the Hemato Polyvalent antivenom, which also uses D. siamensis venom as an immunogen, but binding levels were dramatically reduced when using comparator monovalent antivenoms manufactured against different snake species. A similar pattern was observed when investigating neutralization of coagulopathy, with the procoagulant action of all four geographical venom variants neutralized by both the D. siamensis monovalent and the Hemato Polyvalent antivenoms, while the comparator monovalent antivenoms were ineffective. These in vitro findings translated into therapeutic efficacy in vivo, as the D. siamensis monovalent antivenom was found to effectively protect against the lethal effects of all four geographical venom variants preclinically. Assessments of in vivo nephrotoxicity revealed that D. siamensis venom (700 μg/kg) significantly increased plasma creatinine and blood urea nitrogen levels in anaesthetised rats. The intravenous administration of D. siamensis monovalent antivenom at three times higher than the recommended scaled therapeutic dose, prior to and 1 h after the injection of venom, resulted in reduced levels of markers of nephrotoxicity and prevented renal morphological changes, although lower doses had no therapeutic effect.
CONCLUSIONS/SIGNIFICANCE: This study highlights the potential broad geographical utility of the Thai D. siamensis monovalent antivenom for treating envenomings by the Eastern Russell's viper. However, only the early delivery of high antivenom doses appears to be capable of preventing venom-induced nephrotoxicity.

Matched MeSH terms: Blood Urea Nitrogen
Composition of normal urine in students of the University of Malaya

Chandra N, Bhattathiry EP

Trop Geogr Med, 1967 Dec;19(4):300-3.
PMID: 5585976
Matched MeSH terms: Urea/urine
Effects of fasting during Ramadan on urinary excretion in Malaysian Muslims

Cheah SH, Ch'ng SL, Husain R, Duncan MT

Br J Nutr, 1990 Mar;63(2):329-37.
PMID: 2334668

Urine analysis was conducted on male Muslims before, during and after Ramadan. Various changes in urine volume, osmolality, total solute, sodium, potassium, titratable acidity and urea in response to altered feeding and activity regimens were found. There were no detectable levels of ketones, protein, glucose, urobilinogen and haemoglobin. It was concluded that the body adapted to fasting during Ramadan and that there were no adverse effects on renal function.

Matched MeSH terms: Urea/urine
Improving protein production of indigenous microalga Chlorella vulgaris FSP-E by photobioreactor design and cultivation strategies

Chen CY, Lee PJ, Tan CH, Lo YC, Huang CC, Show PL, et al.

Biotechnol J, 2015 Jun;10(6):905-14.
PMID: 25865941 DOI: 10.1002/biot.201400594

Fish meal is currently the major protein source for commercial aquaculture feed. Due to its unstable supply and increasing price, fish meal is becoming more expensive and its availability is expected to face significant challenges in the near future. Therefore, feasible alternatives to fish meal are urgently required. Microalgae have been recognized as the most promising candidates to replace fish meal because the protein composition of microalgae is similar to fish meal and the supply of microalgae-based proteins is sustainable. In this study, an indigenous microalga (Chlorella vulgaris FSP-E) with high protein content was selected, and its feasibility as an aquaculture protein source was explored. An innovative photobioreactor (PBR) utilizing cold cathode fluorescent lamps as an internal light source was designed to cultivate the FSP-E strain for protein production. This PBR could achieve a maximum biomass and protein productivity of 699 and 365 mg/L/day, respectively, under an optimum urea and iron concentration of 12.4 mM and 90 μM, respectively. In addition, amino acid analysis of the microalgal protein showed that up to 70% of the proteins in this microalgal strain consist of indispensable amino acids. Thus, C. vulgaris FSP-E appears to be a viable alternative protein source for the aquaculture industry.

Matched MeSH terms: Urea/metabolism; Urea/chemistry
Fulltext Nephroprotective Effect of Herbal Extract Eurycoma longifolia on Paracetamol-Induced Nephrotoxicity in Rats

Chinnappan SM, George A, Thaggikuppe P, Choudhary Y, Choudhary VK, Ramani Y, et al.

Evid Based Complement Alternat Med, 2019;2019:4916519.
PMID: 31214269 DOI: 10.1155/2019/4916519

Paracetamol (PCM) is a well-known drug widely used for its analgesic and antipyretic properties. PCM is generally considered as safe but overdose of PCM can cause nephrotoxicity. Traditionally, herbs have been used for the treatment of drug or toxin-induced renal disorders and numerous medicinal plants were tested for nephroprotection effect in PCM-induced nephrotoxicity model. The aim of the present study was to evaluate the protective effect of the herbal extract Eurycoma longifolia (EL) against PCM-induced nephrotoxicity rat model. Forty Wistar rats were randomly divided into five groups of eight rats each: control (vehicle 10 ml/kg), PCM alone (200 mg/kg PCM), EL 100 (EL 100 mg/kg+200 mg/kg PCM), EL 200 (EL 200 mg/kg+200 mg/kg PCM), and EL 400 (EL 400 mg/kg+200 mg/kg PCM). All animals from control group received vehicle daily and animals from groups PCM alone, EL 100, EL 200, and EL 400 received repeated dose of PCM and the assigned treatment of EL daily for a period of 14 days. On the 15th day, serum creatinine, blood urea nitrogen, protein, and albumin were measured in blood and creatinine clearance was measured in urine collected over 24 hours. Kidney sections of all experimental groups underwent histopathological analysis. There was a significant (p<0.05) increase in serum creatinine and blood urea levels in the PCM alone group compared to the treatment groups due to nephrotoxicity. In the treatment groups, there was a dose-dependent protection against PCM-induced changes observed in serum total protein, albumin, urea, and creatinine. Significant (p<0.05) drop was seen in serum creatinine and blood urea content in EL 200 and EL 400 groups. Creatinine clearance significantly increased for EL 200 (p<0.01) and EL 400 (p < 0.001) groups. Serum total protein and serum albumin content were significantly increased (p<0.05) in EL 200 and EL 400 groups compared to PCM alone group. Histopathological examination (H&E staining) of the rat kidneys revealed severe degeneration in the PCM alone group, while there was evidence of significant dose-dependent protection in the treatment groups against PCM-induced changes. The serum and urine biochemical results and histopathology analysis of the kidney indicate the nephroprotective potential of EL extract against PCM-induced nephrotoxicity.

Matched MeSH terms: Blood Urea Nitrogen; Urea
Osteonecrosis with renal damage in HIV patients undergoing HAART

Chitra P, Bakthavatsalam B, Palvannan T

Biomed Pharmacother, 2014 Sep;68(7):881-5.
PMID: 25194446 DOI: 10.1016/j.biopha.2014.07.017

Rheumatoid arthritis in HIV patients undergoing HAART is associated with increased risk of side effect. Elevation of uric acid (UA) is important in tissue damage, deposition of crystal in joints leads to the development of rheumatoid arthritis in the HAART complaint group. This study was carried out to investigate the relationship of uric acid, RA factor, ANA, ESR, cystatin C, urea and creatinine in the HAART complaint group. Moreover; the ratio of uric acid/cystatin C, uric acid/urea and uric acid/creatinine were also studied. To analyze the progression of HIV, the immunological parameters were correlated with uric acid. Our result showed a statistically high significant increase in uric acid, RA factor, ANA, ESR, cystatin C, urea and creatinine in the HAART complaint group when compared to HAART non-complaint group, early stage and control. The ratio of uric acid/cystatin C, uric acid/urea, uric acid/creatinine were significantly increased in the HAART complaint group. Statistically significant positive correlation was observed between uric acid and cystatin C, urea, creatinine, absolute CD4 and CD8 count. The increased level of uric acid, RA factor, ANA, ESR, cystatin C and increased ratio of uric acid/cystatin C in the HAART complaint group might conclude the mechanism underlying the increased risk for rheumatoid arthritis in the HAART complaint group which may relate to the combined effects of low-grade inflammation and renal dysfunction.

Study done in India

Matched MeSH terms: Urea/metabolism
Fulltext Deposition of NiO Nanoparticles on Nanosized Zeolite NaY for Production of Biofuel via Hydrogen-Free Deoxygenation

Choo MY, Oi LE, Daou TJ, Ling TC, Lin YC, Centi G, et al.

Materials (Basel), 2020 Jul 11;13(14).
PMID: 32664579 DOI: 10.3390/ma13143104

Nickel-based catalysts play an important role in the hydrogen-free deoxygenation for the production of biofuel. The yield and quality of the biofuel are critically affected by the physicochemical properties of NiO supported on nanosized zeolite Y (Y65, crystal size of 65 nm). Therefore, 10 wt% NiO supported on Y65 synthesized by using impregnation (IM) and deposition-precipitation (DP) methods were investigated. It was found that preparation methods have a significant effect on the deoxygenation of triolein. The initial rate of the DP method (14.8 goil·h-1) was 1.5 times higher than that of the IM method (9.6 goil·h-1). The DP-Y65 showed the best deoxygenation performance with a 80.0% conversion and a diesel selectivity of 93.7% at 380 °C within 1 h. The outstanding performance from the DP method was due to the smaller NiO particle size (3.57 ± 0.40 nm), high accessibility (H.F value of 0.084), and a higher Brönsted to Lewis acidity (B/L) ratio (0.29), which has improved the accessibility and deoxygenation ability of the catalyst. The NH4+ released from the decomposition of the urea during the DP process increased the B/L ratio of zeolite NaY. As a result, the pretreatment to convert Na-zeolite to H-zeolite in a conventional zeolite synthesis can be avoided. In this regard, the DP method offers a one-pot synthesis to produce smaller NiO-supported nanosized zeolite NaY with a high B/L ratio, and it managed to produce a higher yield with selectivity towards green diesel via deoxygenation under a hydrogen-free condition.

Matched MeSH terms: Urea
Biochemical studies in Presbytis cristata infected with subperiodic Brugia malayi

Choong MF, Mak JW

Trop. Med. Parasitol., 1991 Mar;42(1):71-2.
PMID: 1675809

The Presbytis cristata--Brugia malayi model, now established as a reliable non-human primate model for the experimental screening of potential filaricides, was monitored at monthly intervals for changes in the liver and renal function tests and also for alkaline phosphatase levels during infection. Animals infected with 200-400 infective larvae became patient at 50-90 days post-infection and geometric mean microfilarial counts were above 1000 per ml from the fourth month onwards. There were no significant changes in the biochemical parameters monitored throughout the period of observation. This is an important observation as any changes seen in these parameters during experimental drug studies can be attributed to drug reaction or toxicity and this will be invaluable in decision making as to drug safety.

Matched MeSH terms: Blood Urea Nitrogen
In-vitro bioactivity, biocompatibility and dissolution studies of diopside prepared from biowaste by using sol-gel combustion method

Choudhary R, Vecstaudza J, Krishnamurithy G, Raghavendran HRB, Murali MR, Kamarul T, et al.

Mater Sci Eng C Mater Biol Appl, 2016 Nov 01;68:89-100.
PMID: 27524000 DOI: 10.1016/j.msec.2016.04.110

Diopside was synthesized from biowaste (Eggshell) by sol-gel combustion method at low calcination temperature and the influence of two different fuels (urea, l-alanine) on the phase formation temperature, physical and biological properties of the resultant diopside was studied. The synthesized materials were characterized by heating microscopy, FTIR, XRD, BET, SEM and EDAX techniques. BET analysis reveals particles were of submicron size with porosity in the nanometer range. Bone-like apatite deposition ability of diopside scaffolds was examined under static and circulation mode of SBF (Simulated Body Fluid). It was noticed that diopside has the capability to deposit HAP (hydroxyapatite) within the early stages of immersion. ICP-OES analysis indicates release of Ca, Mg, Si ions and removal of P ions from the SBF, but in different quantities from diopside scaffolds. Cytocompatability studies on human bone marrow stromal cells (hBMSCs) revealed good cellular attachment on the surface of diopside scaffolds and formation of extracellular matrix (ECM). This study suggests that the usage of eggshell biowaste as calcium source provides an effective substitute for synthetic starting materials to fabricate bioproducts for biomedical applications.

Matched MeSH terms: Urea/chemistry
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

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