Assessment of vitamin D status and vitamin D receptor polymorphism in Egyptian children with Type 1 diabetes.

BACKGROUND: The endocrine system of vitamin D regulates about 3 % of the human genome. Vitamin D exerts its actions via a nuclear vitamin D receptor (VDR) which in turn regulates insulin secretion from the pancreas. VDR gene polymorphisms could have an impact on how autoimmune illnesses like Type 1 diabetes mellitus (T1DM) develop. We aimed to explore the relation between T1DM and VDR gene polymorphisms in Egyptian diabetic children and their siblings. METHODS: Enzyme-linked immunosorbent assay was used to quantify 25(OH) vitamin D in the study, which had 179 participants (group 1 = 85 diabetic children, group 2 = 57 siblings of the patients, group 3 = 37 healthy controls). Real-time polymerase chain reaction (RT-PCR) was used to analyze the genotyping of the VDR gene polymorphisms Apa-I (rs7975232), Fok-I (rs2228570), Taq-I (rs731236) and Bsm-I (rs1544410). RESULTS: The mean serum 25(OH) vitamin D levels was significantly lower in T1DM patients (14.99 ± 9.24 ng/mL) and siblings (16.31 ± 7.96 ng/mL) compared to the controls (19.48 ± 7.42 ng/mL) (p = 0.031). The genotypes distribution of VDR Fok-I (rs2228570) and Bsm-I (rs1544410) polymorphisms showed a significant difference between patients, siblings and controls as P = 0.001 and 0.026 respectively, while the VDR ApaI and TaqI polymorphisms did not. FokI-A allele frequency was significantly lower in T1DM patients and siblings than in controls (p < 0.001). FokI-AA genotype had a statistical significant higher vitamin D levels than other genotypes with p value of 0.024. CONCLUSION: Our study found that T1DM children had lower vitamin D levels, and VDR FokI and BsmI gene polymorphisms were linked to T1DM in Egyptian children. Determining the relationship between vitamin D levels and VDR polymorphisms, particularly the FokI and other genetic analyses may aid in the early diagnosis of T1DM in children.

In Vivo Evaluation of the Pharmacokinetic Interaction between Levothyroxine and Amiodarone in Rat Plasma: Evaluation of Importance of Therapeutic Drug Monitoring during Co-Therapy.

Amiodarone-induced thyrotoxicosis (AIT) is a common condition in patients who are receiving amiodarone for cardiac arrhythmia. This risk is elevated in iodine-deficient regions. Levothyroxine is the standard treatment for patients with hypothyroidism. This investigation is concerned with the evaluation of the possible pharmacokinetic interaction between amiodarone and levothyroxine upon co-therapy in rats and to investigate the cause of thyrotoxicosis. A selective, sensitive and precise RP-HPLC method was developed for the simultaneous determination of levothyroxine and amiodarone in rat plasma. A stationary phase of C18 Xterra RP column and a mobile phase consisting of acetonitrile: acidified water with 0.1% trifluoracetic acid (pH = 4.8) with gradient elution were used. The experiment was conducted at ambient temperature with flow rate of 1.5 mL/min for the chromatographic separation and quantitation of the investigated drugs. Protein precipitation with methanol was applied for the analysis of the two drugs in rat plasma. The method was linear over concentration range of 5-200 µg/mL for both levothyroxine and amiodarone. The European Medicines Agency guideline was applied for the validation of the developed bioanalytical method. The method was successfully applied to in vivo pharmacokinetic study in which levothyroxine and amiodarone were quantified in plasma of rats after receiving an oral dose of levothyroxine and amiodarone. After the calculation of the pharmacokinetic parameters, a statistical analysis was performed to elucidate the existence of significant difference between test and control groups in rats. The combination of levothyroxine and amiodarone significantly decreased levothyroxine bioavailability in rats, making the therapeutic drug monitoring mandatory in patients receiving levothyroxine and amiodarone. In addition, the increased clearance of levothyroxine upon the co-administration with amiodarone may explain the reported hypothyroidism.

An innovative combination of Box-Behnken design and ecofriendly approaches for the simultaneous determination of aspirin, clopidogrel, atorvastatin and rosuvastatin in their fixed-dose combination tablets.

Three-levels Box-Behnken design was used in the experimental design approach for the optimization of chromatographic parameters to achieve the optimum resolution and sharp peak shape within a reasonable run time. A method that is sensitive, reliable, and selective was constructed and validated for the simultaneous measurement of a combination therapy that contains blood-thinning and cholesterol-lowering compounds. The four cited drugs namely, aspirin (ASP), clopidogrel (CLP), atorvastatin (ATV) and rosuvastatin (ROS) were estimated in bulk and in pharmaceutical dosage forms in line with International Council for Harmonization guidelines. The separation was done utilizing Kinetex 2.6 C18 column (100 mm, 4.6 mm, 5 m) and RP-HPLC with diode array detector. The separation of the cited drugs and the degradation product of ASP was achieved with mobile phase composed of acetonitrile: KH2PO4 buffer in a gradient mode with pH 3.2 at room temperature. The four drugs were linear over the concentration range (0.05-50 µg/mL). The technique is feasible to be used in quality control laboratories. To picture the green profile of the developed method, four greenness assessment tools were applied. National environmental methods index (NEMI), analytical eco-scale assessment (ESA), green analytical procedure index (GAPI) and analytical greenness metric (AGREE) are the most widely used metrics. They were employed to evaluate the greenness profile of the proposed method and to perform a detailed greenness comparison between the developed method and some of the reported methods for the determination of the investigated drugs. The developed method was found to be relatively green with 0.54 AGREE score.

AGREE and ESA for Greenness Assessment of a Novel Validated RP-HPLC Method for Simultaneous Determination of Aspirin, Warfarin and Clopidogrel in Rat Plasma: Application to Pharmacokinetic Study of the Possible Interaction between the Three Drugs.

The green profile of the developed method is assessed and compared with previously reported methods. Percutaneous coronary intervention is a procedure where a catheter is utilized to place a stent in order to facilitate opening of the blood vessels in the heart. Triple antithrombotic therapy includes oral anticoagulation as warfarin and dual antiplatelet therapy (composed of aspirin and clopidogrel bisulfate). The aim of the current study was to evaluate the pharmacokinetic parameters of ASP, WAR and CLP and to investigate the possible interaction between the three drugs upon co-administration in rats. A selective and precise RP-HPLC method was developed for the simultaneous determination of ASP, WAR and CLP in rat plasma. Pharmacokinetic study was conducted in rats that received ASP, WAR and CLP as an application of the developed method. From the statistical evaluation of the pharmacokinetic parameters, it was observed that the co-administration of ASP, WAR and CLP significantly increased the ASP and CLP bioavailability in rats. A significant drug-drug interaction was confirmed in the current study. The elevated Cmax of ASP and CLP upon the co-administration of ASP, WAR and CLP may explain the reported bleeding.

An eco-friendly ultra-performance liquid chromatography-mass spectrometry method for quantification of rivaroxaban and ticagrelor in rat plasma: grapefruit interactions.

Aim: An eco-friendly ultra-performance liquid chromatography-tandem mass spectrometry method was developed to study the pharmacokinetics of rivaroxaban and ticagrelor in rat plasma, utilizing moxifloxacin as an internal standard. The food-drug interaction between grapefruit juice and these drugs was also investigated. Methods: Liquid-liquid extraction was used. A nonporous stationary phase Agilent® Poroshell 120EC C18 column was used with methanol: 0.1% aqueous formic acid (95:5 v/v) as a mobile phase. The detection was performed in multiple reaction monitoring mode using positive electrospray ionization. The method's validation was conducted in accordance with US FDA and European Medicines Agency guidelines. Results & conclusion: Grapefruit juice should be ingested with caution in patients treated with antithrombotic medications as it may increase their plasma concentration, inducing bleeding, and requires close clinical monitoring.

Plackett-Burman and face-centered composite designs for development and optimization of chromatographic method for the simultaneous determination of glycopyrronium, indacaterol and mometasone in their fixed dose combination inhaler - Green profile assessment.

A novel simple, specific, sensitive, accurate and precise reversed phase high performance liquid chromatographic method (RP-HPLC/UV) was developed and validated for the simultaneous estimation of Glycopyrronium bromide (GLY), Indacaterol acetate (IND) and Mometasone furoate (MOF) in pure form, in laboratory prepared mixtures and in pharmaceutical dosage form. Experimental design methodology was applied by using Plackett-Burman and face-centered composite designs to achieve the best resolution with minimum experimental trials. The designed model was statistically analyzed, graphically presented by surface plots and the relationships between coefficients of the derived polynomial equations were interpreted. Chromatographic separation was achieved on Inertsil ODS C18 column (250 ×4.6 mm, 5 µm) at ambient temperature using a mobile phase composed of methanol: 0.1% glacial acetic acid (pH4) in a gradient elution at a flow rate 1 mL /min. UV detection was carried out at 233 nm. Response was found to be linear in the concentration range of 20-120 µg /mL with regression coefficient (r2 = 0.999) for GLY, 50-300 µg /mL with regression coefficient (r2 = 0.9995) for IND and 50-300 µg /mL with regression coefficient (r2 = 0.9998) for MOF. The method was validated as per ICH guidelines and satisfactory results were achieved. The method was successfully applied for the analysis of the cited drugs in their fixed dose combination (FDC) pharmaceutical formulation. Statistical comparison between the results obtained by the proposed method and the reference methods for GLY, IND and MOF showed no significant difference. The developed method could be implemented in quality control aspects of the cited drugs. Four green metrics were used to evaluate the new RP-HPLC/UV method's greenness and compare it to other published techniques.

Validated LC/MS/MS Method for the Determination of Rivastigmine in Human Plasma: Application to a Pharmacokinetic Study in Egyptian Volunteers to Determine the Effect of Gender and Body Mass Index.

The effect of gender and body mass index (BMI) on the pharmacokinetics of rivastigmine was studied in Egyptian human subjects using new bio-analytical validated LC/MS/MS method. In this study, Rivastigmine was estimated in human plasma using Escitalopram as an internal standard (IS). Rivastigmine and Escitalopram were extracted from human plasma samples by liquid-liquid extraction using diethyl ether (DEE)-dichloromethane (DCM) (70:30, v/v). Chromatographic separation was performed on a reversed phase C18 INERTSIL ODS column using 0.05% aqueous formic acid, acetonitrile in the ratio (50:50, v/v) as a mobile phase. Multiple reaction monitoring (MRM) was applied and operated by positive mode electrospray ionization. A significant difference between male and female Cmax (maximum plasma concentration) (P = 0.0205; CL = 95.4) was found using Mann-Whitney U test. Also, a moderate negative correlation was found between BMI and Tmax (time to peak plasma concentration) using spearman rho test. The calculated results confirm the difference of Rivastigmine pharmacokinetics between male and female subjects. Furthermore, it indicates that Rivastigmine dose adjustment may be necessary. The method was applied for the estimation of pharmacokinetic parameters in volunteers (n = 26, 17 male and 9 female) and the effects of gender and BMI were investigated.

A Turn-On-Type Fluorescence Resonance Energy Transfer Eco-friendly Method for Nitazoxanide Quantification in Pharmaceutical Dosage Form and Spiked Plasma: Evaluation of Greenness Profile Using Different Assessment Tools.

A brand-new class of anti-infective drugs that work against bacteria, viruses, and protozoan parasites is nitazoxanide and related thiazolides. Thiazolides have also been shown to cause cell cycle arrest and apoptotic cell death in cancer cells in recent years. In this study, an eco-friendly, spectrofluorimetric technique that is verified, easy, and sensitive has been proposed for quantifying nitazoxanide (NTZ), a broad-spectrum antiparasitic drug. When NTZ is reduced with zinc (Zn) powder in an acidic media, a highly fluorescent product is produced. To get the highest sensitivity, different experimental conditions impacting the response were examined and optimized. Following excitation at 299 nm, scanning of the fluorescent product was done at 440 nm. The intensity of the fluorescence was proportional to the drug concentration in the range of 0.1-0.6 µg/mL. The approach was validated according to International Conference on Harmonization (ICH) guidelines, and the outcome was satisfactory. The detection and quantitation limits were calculated to be 0.013 and 0.038 µg/mL, respectively. The suggested technique was successful in analyzing commercially available NTZ dosage forms. Furthermore, the proposed technique was used to assess NTZ levels in human plasma and it was bio-analytically validated according to European Medicines Agency (EMA) guidelines. The suggested method can be used in quality control laboratories as well as in pharmacokinetic studies. In order to picture the green profile of the developed method, four greenness assessment tools have been applied. National Environmental Methods Index (NEMI), analytical Eco-Scale Assessment (ESA), Green Analytical Procedure Index (GAPI) and Analytical Greenness metric (AGREE) are the relatively most widely used metrics. So, they were utilized to perform a detailed greenness comparison between the proposed method and some of the reported methods for the determination of NTZ. The developed method was found to be an excellent green method with the highest AGREE score.

Core shell stationary phase for a novel separation of some COVID-19 used drugs by UPLC-MS/MS Method: Study of grapefruit consumption impact on their pharmacokinetics in rats.

A sensitive and selective UPLC-MS/MS method was developed for the synchronized determination of four drugs used in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), namely, azithromycin, apixaban, dexamethasone, and favipiravir in rat plasma. using a Poroshell 120 EC-C18 column (50 mm × 4.6 mm, 2.7 m) with a high-resolution ESI tandem mass spectrometer detection with multiple reaction monitoring. We used an Agilent Poroshell column, which is characterized by a stationary phase based on non-porous core particles. With a remarkable improvement in the number of theoretical plates and low column backpressure. In addition, the developed method was employed in studying the potential food-drug interaction of grapefruit juice (GFJ) with the selected drugs which affects their pharmacokinetics in rats. The LC-MS/MS operated in positive and negative ionization mode using two internal standards: moxifloxacin and chlorthalidone, respectively. Liquid- liquid extraction of the cited drugs from rat plasma was accomplished using diethyl ether: dichloromethane (70:30, v/v). The analytes were separated using methanol: 0.1 % formic acid in water (95: 5, v/v) as a mobile phase in isocratic mode of elution pumped at a flow rate of 0.3 mL/min. A detailed validation of the bio-analytical method was performed in accordance with US-FDA and EMA guidelines. Concerning the in vivo pharmacokinetic study, the statistical significance between the results of the test groups receiving GFJ along with the cited drugs and the control group was assessed demonstrating that GFJ increased the plasma concentration of azithromycin, apixaban, and dexamethasone. Accordingly, this food-drug interaction requires cautious ingestion of GFJ in patients using (SARS-CoV-2) medications as it can produce negative effects in the safety of the drug therapy. A potential drug-drug interaction is also suggested between those medications requiring a suitable dose adjustment.

Hearing assessment in Egyptian children with chronic renal failure on regular hemodialysis and renal transplantation children.

INTRODUCTION: Hearing impairment is frequent in patients with end-stage renal disease (ESRD). We aimed to assess the prevalence of hearing impairment in children on regular hemodialysis and renal transplantation. MATERIALS AND METHODS: Transient-evoked otoacoustic emissions (TEOAEs) has been done for 80 children on regular hemodialysis and 40 with renal transplant. RESULTS: In hemodialysis group, TEOAEs showed that 53.8% children had hearing affection, it was significantly related to dialysis duration, dialysis adequacy, vascular access infection, hepatitis C virus (HCV) infection, and ototoxic drugs (p = 0.001, 0.037, 0.011, 0.004, 0.030, 0.007, and 0.044, respectively). In renal transplant group hearing impairment was 25%. There was significant relation with period of dialysis before transplantation and biopsy proved rejection (p = 0.008, <0.001, respectively). CONCLUSION: Hearing impairment is a common finding in ESRD patients. Thus audiological assessment must be done in these patients.

RP-HPLC-DAD Method Development and Validation for Simultaneous Determination of Lansoprazole, Tinidazole, Amoxicillin, and Naproxen in Their Raw Materials and Combined Dosage Form: DOE Approach for Optimization of the Proposed Method.

BACKGROUND: Helicobacter pylori infection is a common cause of peptic ulcer disease and dyspepsia. In addition, it may result in gastric cancer and gastric mucosa associated lymphoid tissue lymphoma. First-line therapy usually consists of triple therapy containing clarithromycin or amoxicillin, one of the proton pump inhibitors, and metronidazole or tinidazole. In addition to the triple therapy, an analgesic is required to relieve pain such as naproxen. OBJECTIVE: A sensitive and selective method needs to be developed and validated for simultaneous determination of four drugs (amoxacillin, tinidazole, naproxen and lansoprazole), used for treating Helicobacter pylori infection, in their combined dosage forms. METHODS: With the aid of experimental design, the cited drugs were separated and quantified. HPLC with a diode array detector was used and metronidazole, one of the drugs also used for treatment, was the internal standard (IS). A Thermo Scientific BDS Hypersil C18 column (5 µm, 250 mm x 4.6 mm) with mobile phase composed of acetonitrile-water (40 + 60, by volume), pH 5 adjusted with phosphoric acid, at 30°C was used for the separation of the cited drugs. RESULTS: The method was linear over the concentration ranges 10-500 µg/mL for amoxacillin, 10-350 µg/mL for tinidazole, 10-250 µg/mL for naproxen, and 2-20 µg/mL for lansoprazole. The proposed method was fully validated according to International Conference of Harmonization (ICH) guidelines. Statistical analysis revealed no significant difference between the results obtained and the four reference methods for the investigated drugs. CONCLUSION: The method can be easily implemented in QC studies of the cited drugs in their dosage forms. HIGHLIGHTS: Experimental design was applied using Plackett-Burman design for preliminary screening of factors followed by Box-Behnken design for chromatographic method optimization.

Development and Bio-Analytical Validation of Chromatographic Determination Method of Rufinamide in Presence of its Metabolite in Human Plasma.

Rufinamide (RF), antiepileptic drug, is biotransformed to inactive metabolite. Frequent plasma monitoring is required for dose adjustment. This work is concerned with the development and validation of a sensitive and selective RP-HPLC method for the quantitative determination of RF in spiked human plasma in the presence of its main metabolite. Lacosamide was selected as internal standard. Preparation of plasma samples involved precipitation of plasma proteins using methanol. Isocratic elution mode was applied and the chromatographic separation was performed on Prontosil CN column (5 µm, 250 × 4.6 mm). Good resolution was achieved using acetonitrile: water (10:90, v/v, adjusted with 0.01 N aqueous solution of o-phosphoric acid to pH = 3) as a mobile phase at a flow rate of 1 mL/min, and UV detection was carried out at 210 nm. Linearity was observed over the concentration range of 0.5-50 µg/mL of RF in plasma. Bio-analytical validation of the developed method was carried out in accordance to the European Medicines Agency guidelines. The accuracy ranged from 95.97 to 114.13%, and the coefficient of variation of the assay intra-day and inter-day precision did not exceed 10%. The samples were stable under the employed experimental conditions. In conclusion, the findings of the present study revealed its usefulness for therapeutic drug monitoring, assessment of drug pharmacokinetics and application for bioequivalence study.

Determination of Rufinamide in the Presence of 1-[(2,6-Difluorophenyl)Methyl]-1H-1,2,3-Triazole-4 Carboxylic Acid Using RP-HPLC and Derivative Ratio Methods as Stability Indicating Assays to Be Applied on Dosage Form.

BACKGROUND: Rufinamide is a triazole derivative that is structurally dissimilar to other marketed antiepileptic drugs, has been assumed a marketing authorization, by the European Union and FDA, for use as a complementary therapy for seizures associated with Lennox-Gastaut syndrome. OBJECTIVE: This work is concerned with development of two methods for determination of rufinamide (RUF) in presence of 1-[(2,6-difluorophenyl)methyl]-1H-1,2,3-triazole-4 carboxylic acid as its alkaline degradation product in dosage form. METHODS: The first method was capable of determing RUF in the presence of its alkaline degradation product and in dosage form. Kromasil C8 column and mobile phase consisting of acetonitrile-water (50:50, v/v) were used and UV detection at 210 nm. In the second method, first derivative ratio spectrophotometry, RUF was determined by measuring peak amplitude at 269.5 nm over 5-30 µg/mL. RESULTS: The linearity range of RUF was 10-90 µg/mL for HPLC method covering its therapeutic range with r2 = 0.9999. Forced degradation under alkaline conditions was carried out, the degradation product was isolated and its structure was confirmed. Both methods were validated in accordance to ICH guidelines. Statistical analysis revealed no significant difference between obtained results and reported ones. CONCLUSION: The present study is useful for therapeutic drug monitoring and routine analysis of RUF in quality control laboratories. HIGHLIGHTS: Kinetics of the alkaline degradation of RUF was studied by following the concentration of the remaining drug until complete degradation was achieved.

Role of Matrix Metalloproteinase-9 in Neonatal Hypoxic-Ischemic Encephalopathy.

BACKGROUND: Neonatal encephalopathy is a heterogeneous syndrome characterised by signs of central nervous system dysfunction in the newborn. Matrix metalloproteinase-9(MMP-9) increases the blood-brain barrier permeability, and their inhibitors can reduce its damage. MMP-9 has been implicated specifically in cerebral ischemia. AIM: To measure serum MMP-9 in neonatal hypoxic-ischemic encephalopathy and evaluate its correlation to the severity of early prediction and treatment. METHODS: its case-control study. The serum concentration of MMP-9 was determined by ELISA in 100 hypoxic neonates and 50 healthy neonates of matched age and sex who served as controls. RESULTS: In our present study the serum MMP-9 level was significantly higher at p = 0.0001 in hypoxic-ischemic full-term newborns (176.7 ± 68.7 ng/ml)as compared to control newborn (69.4 ± 34.85 ng/ml)and it was significantly higher at p = 0.0075 in hypoxic-ischemic preterm newborn (171.2 ± 132.9 ng/ml) when compared to control newborn (72.54 ± 36.74 ng/ml), also MMP-9 was significantly higher at Sarnat stage III at p = 0.0001. CONCLUSION: Serum MMP-9 level was significantly higher in hypoxic-ischemic newborns, and significantly increased with severity, so we suggest that serum MMP-9 level is important for predicting neurological sequel and severity in neonatal encephalopathy.

Determination of four antiepileptic drugs in plasma using ultra-performance liquid chromatography with mass detection technique.

Status epilepticus (SE) is considered the second most frequent neurological emergency. Its therapeutic management is performed using sequential antiepileptic drug regimens. Diazepam (DIA), midazolam (MID), phenytoin (PHT) and phenobarbital (PB) are four drugs of different classes used sequentially in the management of SE. A sensitive, selective, accurate and precise method was developed and validated for simultaneous determination of the four antiepileptic drugs in human plasma. Their separation and quantification were achieved using ultra-performance liquid chromatography (UPLC) with mass detection using carbamazepine as internal standard (IS). For the first three drugs and the IS, UPLC-MS/MS with electrospray ionization working in multiple reaction monitoring mode was used at the following transitions: m/z 285 → 193 for DIA; m/z 326 → 291 for MID; m/z 253 → 182 for PHT; and m/z 237 → 194, 237 → 192 for IS. For the fourth drug (PB), a molecular ion peak of PB [M + H] + at m/z 233 was used for its quantitation. The method was linear over concentration ranges 5-500 ng/mL for DIA and MID and 0.25-20 µg/mL for PHT and PB. Bioanalytical validation of the developed method was carried out according to European Medicines Agency guidelines. The developed method can be applied for routine drug analysis, therapeutic drug monitoring and bioequivalence studies.