High-resolution capillary electrophoresis for the determination of carbamylated albumin

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Julien Favresse ◽  
Joris Delanghe
Keyword(s):  
Separation Efficiency ◽  
Theoretical Plate ◽  
Clinical Routine ◽  
Negative Prognostic Factor ◽  
Symmetry Factor ◽  
Primary Amino ◽  
The Mean ◽  
Dose Dependent

Abstract Objectives Carbamylation is a non-enzymatic post-translational reaction of a primary amino group of a protein with isocyanate. The albumin carbamylation is a negative prognostic factor in chronic kidney disease (CKD) patients and induce charge difference implying an observed shift in electrophoretic mobility that can be measured through a symmetry factor (SF). Methods The Helena V8 and the Sebia Capillarys 2 systems were used for all experiments. The effect of in vitro carbamylation on the SF by spiking increasing concentrations of potassium isocyanate (KCNO) in serum of three healthy volunteers was investigated. Theoretical plate numbers (N) as a surrogate of separation efficiency were also calculated and correlations between SF and renal function biomarkers were performed on 284 patients. Results A dose-dependent impact of KCNO on the SF was observed for both methods with the Helena V8 being more sensitive. The mean N was significantly higher on the Helena V8 as compared to the Sebia Capillarys 2 (2,972 vs. 444.1, p<0.0001). The SF correlated significantly with eGFR (r=0.50, p<0.0001), creatinine (r=−0.31, p<0.0001) and urea (r=−0.34, p<0.0001) on the Helena V8. On the Sebia Capillarys 2, a significant correlation was only observed with eGFR (r=0.17, p=0.004). A better discrimination between CKD stages was also observed using the Helena V8. Conclusions Thanks to a higher mean N, the Helena V8 might offer new possibilities, including detection of carbamylated albumin through SF calculation. Further studies are still needed to confirm the interest of using this type of assays in clinical routine.

Colorimetric Method for Rapid Determination of Serum Arginase

1967 ◽  
Vol 13 (10) ◽  
pp. 900-908 ◽  
Author(s):  
Brigitta Mellerup
Keyword(s):  
Rapid Determination ◽  
Colorimetric Method ◽  
Normal Range ◽  
Clinical Routine ◽  
Mean Values ◽  
Enzymatic Formation ◽  
Significant Difference ◽  
The Mean ◽  
Normal Men

Abstract A method for the determination of serum arginase is given which combines the enzymatic formation of urea with the sensitive method of Coulombe (1) for measuring this substance. This procedure allows more accurate determinations in the normal range than do previous methods described and is convenient for clinical routine. Significant difference is found between the mean values of normal men and women, 3.9 units/L. for the former and 2.9 units/L. for the latter.

scholarly journals Determination of Diclofenac Sodium in Eagle's Minimum Essential Medium with Earle's Balanced Salt Solution

2003 ◽  
Vol 86 (4) ◽  
pp. 681-684
Author(s):  
Patrícia S Lopes ◽  
Telma M Kaneko ◽  
Carolina Y Takano ◽  
Aurea C L Lacerda ◽  
Leandro R Latorre ◽  
...  
Keyword(s):  
Salt Solution ◽  
Diclofenac Sodium ◽  
Reversed Phase ◽  
Minimum Essential Medium ◽  
In Vitro Permeation ◽  
Hydrophilic Drug ◽  
Permeation Studies ◽  
The Mean

Abstract A validated method was developed for determination of diclofenac sodium, considered a model hydrophilic drug for in vitro permeation studies, in Eagle's Minimum Essential Medium (MEM) with Earle's balanced salt solution. Liquid chromatography was used to determine diclofenac sodium. This method was developed with a reversed-phase column Supercosil LC 18, DB 25 cm × 4.5 mm; the mobile phase was methanol with 3% (v/v) acetic acid–Milli-Q water (74 + 26), and detection was at 283 nm. The detection and quantitation limits were 2.41 × 10–8 and 3.31 × 10–5 μg/μL, respectively. The accuracy within-day (n = 3) and day-to-day (n = 7) was 98.83%; the mean variation coefficient for inter- (n = 7) and intraday precision (n = 3) was 12.20%, thus, not exceeding 15%. This method can be used as an analytical procedure for the determination of diclofenac sodium in MEM for in vitro permeation studies.

Determination of mosquito bloodmeal pH in situ by ion-selective microelectrode measurement: implications for the regulation of malarial gametogenesis

Parasitology ◽  
2000 ◽  
Vol 120 (6) ◽  
pp. 547-551 ◽  
Author(s):  
O. BILLKER ◽  
A. J. MILLER ◽  
R. E. SINDEN
Keyword(s):  
Xanthurenic Acid ◽  
Mosquito Vector ◽  
Dependent Manner ◽  
Ph Increase ◽  
Ph Range ◽  
Dose Dependent

Malarial gametocytes circulate in the peripheral blood of the vertebrate host as developmentally arrested intra-erythrocytic cells, which only resume development into gametes when ingested into the bloodmeal of the female mosquito vector. The ensuing development encompasses sexual reproduction and mediates parasite transmission to the insect. In vitro the induction of gametogenesis requires a drop in temperature and either a pH increase from physiological blood pH (ca pH 7·4) to about pH 8·0, or the presence of a gametocyte-activating factor recently identified as xanthurenic acid (XA). However, it is unclear whether either the pH increase or XA act as natural triggers in the mosquito bloodmeal. We here use pH-sensitive microelectrodes to determine bloodmeal pH in intact mosquitoes. Measurements taken in the first 30 min after ingestion, when malarial gametogenesis is induced in vivo, revealed small pH increases from 7·40 (mouse blood) to 7·52 in Aedes aegypti and to 7·58 in Anophěles stephensi. However, bloodmeal pH was clearly suboptimal if compared to values required to induce gametogenesis in vitro. Xanthurenic acid is shown to extend the pH-range of exflagellation in vitro in a dose-dependent manner to values that we have observed in the bloodmeal, suggesting that in vivo malarial gametogenesis could be further regulated by both these factors.

NE-180, a Novel glycoPEGylated Erythropoietin Demonstrates Dose-Dependent Activity in a Phase 1 Single Dose, Dose Escalating Study in Normal Human Volunteers (NHV).

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1149-1149
Author(s):  
Bruce A. Wallin ◽  
Denise Ramjit ◽  
Michael Seiberling ◽  
David Zopf
Keyword(s):  
Adverse Events ◽  
Animal Studies ◽  
Phase 1 ◽  
Stopping Rules ◽  
Open Label ◽  
Serious Adverse Events ◽  
Maximal Increase ◽  
The Mean ◽  
Dose Dependent

Abstract NE-180 is a glycoPEGylated recombinant human erythropoietin that binds to and activates the erythropoietin (EPO) receptor. It has demonstrated in vitro activities comparable to EPO and an extended serum half-life in animal studies. This may allow less frequent dosing in patients being treated with chronic anemia. METHODS: A single center, open-label study of NE-180, administered as single escalating doses given by the SC or IV route, was conducted to assess the safety, tolerability, PK and PD. Subjects (male or female NHV) were planned to be assigned to one of 4 dose groups, 10 subjects per dose with 5 SC and 5 IV subjects per group: 0.5, 1.5, 3, or 4.5 mg/kg. Each dose group was planned to be initiated in an ascending, sequential fashion unless or until stopping rules were met. RESULTS: 25 NHV (16 females) were enrolled in the first two dose cohorts and have completed 56 day follow-up. The 1.5 mg/kg IV cohort met the protocol-specified Hb rate of rise stopping rule (change in Hb greater than 1 g/dL during any 14 day period). Injections were generally well tolerated with no discontinuations for adverse events or serious adverse events. Reticulocyte increases were dose proportional. Average reticulocyte count at baseline was 1.0±0.3%. The maximal increase occurred at day 7. The mean change from baseline for the 0.5 and 1.5 mg/kg SC group was: 0.9±0.4% and 2.2±0.9%, respectively. The mean change from baseline for the 0.5 and 1.5 mg/kg IV group was: 1.7±0.8% and 2.3±0.8%, respectively. PK data will be presented. CONCLUSIONS: Single doses up to 1.5 mg/kg of NE-180 administered to NHV were generally well tolerated and demonstrated potent dose-dependent erythropoietic activity.

Optimized steps in fluorometric determination of thiobarbituric acid-reactive substances in serum: importance of extraction pH and influence of sample preservation and storage

1993 ◽  
Vol 39 (12) ◽  
pp. 2522-2526 ◽  
Author(s):  
W Wasowicz ◽  
J Nève ◽  
A Peretz
Keyword(s):  
Thiobarbituric Acid ◽  
Thiobarbituric Acid Reactive Substances ◽  
Fluorometric Method ◽  
C Storage ◽  
Insulin Dependent ◽  
The Mean ◽  
Optimized Conditions ◽  
And Storage

Abstract A simple, reliable, and reproducible fluorometric method for measuring thiobarbituric acid-reactive substances (TBARS) in serum is proposed, based on the reaction between malondialdehyde (MDA) and thiobarbituric acid. Formation of TBARS was complete at pH 2.4-2.6, but extraction with n-butanol proved complete only at lower pH, i.e., 1.6-1.7. Analytical recoveries of MDA added to serum were 94%-101%; within- and between-run CVs were 2.4-3.6% and 4.6-5.5%; and the detection limit for TBARS in serum was 0.10 mumol/L. Optimized conditions included: (a) collection of either serum or heparinized plasma, (b) preservation from in vitro autoxidation by glutathione and EDTA, and (c) storage at -20 degrees C up to 35 days. The mean (+/- SD) TBARS concentration in 47 healthy adults was 1.01 (0.21) mumol/L; no sex-related difference was observed. Higher concentrations were measured in patients with renal insufficiency undergoing hemodialysis and in patients with insulin-dependent diabetes, chronic pancreatitis, or liver cirrhosis.

scholarly journals Determination of in vitro antidiabetic effects of Zingiber officinale Roscoe

2012 ◽  
Vol 48 (4) ◽  
pp. 601-607 ◽  
Author(s):  
Naila Abdul Sattar ◽  
Fatma Hussain ◽  
Tahira Iqbal ◽  
Munir Ahmad Sheikh
Keyword(s):  
Therapeutic Potential ◽  
Zingiber Officinale ◽  
Postprandial Glucose ◽  
Protein Glycation ◽  
Zingiber Officinale Roscoe ◽  
In Vitro Effects ◽  
Dose Dependent ◽  
Antidiabetic Effects

Aqueous extracts of Zingiber officinale rhizomes were studied to evaluate their antidiabetic effects on protein glycation and on the diffusion of glucose in vitro in the present study. Zingiber officinale rhizome aqueous extract were examined at concentrations of 5, 10, 20 and 40 g/L. The antidiabetic effects were found to be dose-dependent. Antidiabetic potential of Zingiber officinale was mainly through inhibition of the glucose diffusion and to a limited extent by reducing the glycation. However, further studies are needed to determine in vitro effects of therapeutic potential by restraining postprandial glucose absorptions and plasma protein glycations in diabetic subjects.

scholarly journals Determination of [11C]PBR28 Binding Potential in vivo: A First Human TSPO Blocking Study

2014 ◽  
Vol 34 (6) ◽  
pp. 989-994 ◽  
Author(s):  
David R Owen ◽  
Qi Guo ◽  
Nicola J Kalk ◽  
Alessandro Colasanti ◽  
Dimitra Kalogiannopoulou ◽  
...  
Keyword(s):  
Volume Of Distribution ◽  
Translocator Protein ◽  
Binding Potential ◽  
Healthy Human ◽  
Positron Emission ◽  
Dose Dependent ◽  
In Vitro Data

Positron emission tomography (PET) targeting the 18 kDa translocator protein (TSPO) is used to quantify neuroinflammation. Translocator protein is expressed throughout the brain, and therefore a classical reference region approach cannot be used to estimate binding potential ( BP ND). Here, we used blockade of the TSPO radioligand [11C]PBR28 with the TSPO ligand XBD173, to determine the non-displaceable volume of distribution ( V ND), and hence estimate the BP ND. A total of 26 healthy volunteers, 16 high-affinity binders (HABs) and 10 mixed affinity binders (MABs) underwent a [11C]PBR28 PET scan with arterial sampling. Six of the HABs received oral XBD173 (10 to 90 mg), 2 hours before a repeat scan. In XBD173-dosed subjects, V ND was estimated via the occupancy plot. Values of BP ND for all subjects were calculated using this V ND estimate. Total volume of distribution ( V T) of MABs (2.94 ± 0.31) was lower than V T of HABs (4.33 ± 0.29) ( P<0.005). There was dose-dependent occupancy of TSPO by XBD173 (ED50 = 0.34 ± 0.13 mg/kg). The occupancy plot provided a V ND estimate of 1.98 (1.69, 2.26). Based on these V ND estimates, BP ND for HABs is approximately twice that of MABs, consistent with predictions from in vitro data. Our estimates of [11C]PBR28 V ND and hence BP ND in the healthy human brain are consistent with in vitro predictions. XBD173 blockade provides a practical means of estimating V ND for TSPO targeting radioligands.

Purpurogallin—a natural and effective hepatoprotector in vitro and in vivo

1991 ◽  
Vol 69 (10-11) ◽  
pp. 747-750 ◽  
Author(s):  
Tai-Wing Wu ◽  
Ling-Hua Zeng ◽  
Jun Wu ◽  
Doug Carey
Keyword(s):  
Xanthine Oxidase ◽  
Rat Hepatocytes ◽  
Isolated Hepatocytes ◽  
Oxidase Inhibition ◽  
The Mean ◽  
Xanthine Oxidase Inhibition ◽  
Oxidase Reaction ◽  
Dose Dependent

Purpurogallin is a plant phenol that is sometimes added as an oxidation retardant to fats–oils or to certain fuels or lubricants. However, it was unknown if purpurogallin is cytoprotective. Here we examined this issue, both in isolated hepatocytes and in vivo. From 0.5 to 2.0 mM, purpurogallin prolongs survival of rat hepatocytes substantially against oxyradicals generated with xanthine oxidase and hypoxanthine. The protection was dose dependent and surpassed that given by such antioxidants as ascorbate, mannitol, superoxide dismutase, catalase, and Trolox, when each was examined at or near its optimal concentration in the same system. When 1.5,3, and 6 μmol of purpurogallin in saline were infused into rats with postischemic livers shortly before reperfusion, the mean hepatic salvages were 42, 76, and 86%, respectively. Such salvage effects would rank purpurogallin highly among the hepatoprotectors known. Over the range of 31 to 500 μM, purpurogallin inhibited the rate of O2 consumption in the xanthine oxidase reaction by ~90%, which was 2- to several-fold higher than the inhibition elicited by allopurinol over the same concentrations. Thus, purpurogallin is an effective natural hepatoprotector that may operate partly or principally as an inhibitor of xanthine oxidase.Key words: purpurogallin, hepato-protection, xanthine oxidase inhibition.

scholarly journals Therapeutic Potential of Green Synthesized Copper Nanoparticles Alone or Combined with Meglumine Antimoniate (Glucantime®) in Cutaneous Leishmaniasis

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 891
Author(s):  
Aishah E. Albalawi ◽  
Sobhy Abdel-Shafy ◽  
Amal Khudair Khalaf ◽  
Abdullah D. Alanazi ◽  
Parastoo Baharvand ◽  
...  
Keyword(s):  
Cutaneous Leishmaniasis ◽  
Copper Nanoparticles ◽  
Leishmania Major ◽  
Therapeutic Potential ◽  
No Production ◽  
Dependent Manner ◽  
Meglumine Antimoniate ◽  
The Mean ◽  
Dose Dependent

Background: In recent years, the focus on nanotechnological methods in medicine, especially in the treatment of microbial infections, has increased rapidly. Aim: The present study aims to evaluate in vitro and in vivo antileishmanial effects of copper nanoparticles (CuNPs) green synthesized by Capparis spinosa fruit extract alone and combined with meglumine antimoniate (MA). Methods: CuNPs were green synthesized by C. spinosa methanolic extract. The in vitro antileishmanial activity of CuNPs (10–200 µg/mL) or MA alone (10–200 µg/mL), and various concentrations of MA (10–200 μg/mL) along with 20 μg/mL of CuNPs, was assessed against the Leishmania major (MRHO/IR/75/ER) amastigote forms and, then tested on cutaneous leishmaniasis induced in male BALB/c mice by L. major. Moreover, infectivity rate, nitric oxide (NO) production, and cytotoxic effects of CuNPs on J774-A1 cells were evaluated. Results: Scanning electron microscopy showed that the particle size of CuNPs was 17 to 41 nm. The results demonstrated that CuNPs, especially combined with MA, significantly (p < 0.001) inhibited the growth rate of L. major amastigotes and triggered the production of NO (p < 0.05) in a dose-dependent manner. CuNPs also had no significant cytotoxicity in J774 cells. The mean number of parasites was significantly (p < 0.05) reduced in the infected mice treated with CuNPs, especially combined with MA in a dose-dependent response. The mean diameter of the lesions decreased by 43 and 58 mm after the treatment with concentrations of 100 and 200 mg/mL of CuNPs, respectively. Conclusion: The findings of the present study demonstrated the high potency and synergistic effect of CuNPs alone and combined with MA in inhibiting the growth of amastigote forms of L. major, as well as recovery and improving cutaneous leishmaniasis (CL) induced by L. major in BALB/c mice. Additionally, supplementary studies, especially in clinical settings, are required.

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