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Ahmed Salman,1 Mohamed Salman,2 Ahmed Moustafa,3 Hossam El-Din Shaaban,4 Ahmed El-Mikkawy,5 Safa Labib,1 Ahmed Youssef,1 Mahmoud Gouda Omar,1 Mohamed Matter,6 Hesham Elkassar1 1Internal Medicine Department, Faculty of Medicine, Cairo University, Cairo, Egypt; 2General Surgery Department, Faculty of Medicine, Cairo University, Cairo, Egypt; 3Department of Endemic Medicine and Hepatology, Faculty of Medicine, Cairo University, Cairo, Egypt; 4Gastroenterology Department, National Hepatology and Tropical Medicine Research Institute, Cairo, Egypt; 5Hepatology and Gastroenterology Department, Theodor Bilharz Research Institute, Cairo, Egypt; 6Radiodiagnosis Department, Faculty of Medicine, Alazhar University, Cairo, EgyptCorrespondence: Ahmed SalmanInternal Medicine Department, Faculty of Medicine, Cairo University, 110 L Hadayek Alahram, 11311, Cairo, EgyptTel +201000468664Email awea844@gmail.comPurpose: Radiofrequency ablation (RFA) appears effective for the treatment of hepatocellular carcinoma (HCC). Evaluation of prognostic factors is imperative for patient selection and improving treatment efficacy. This study aimed to assess sarcopenia as a predictor of the outcome of RFA in patients with HCC.Methods: This prospective study included all patients with HCC on top of HCV-related cirrhosis who underwent RFA and followed up for a minimum of two years. CT scan was used to determine the skeletal muscle index at the psoas, erector spinae, quadratus lumborum, transversus abdominis, external and internal obliques, and rectus abdominis muscles. Cross-sectional areas were calculated to obtain a lumbar skeletal muscle index (L3-SMI).Results: A total of 97 patients were enrolled in the study. The L3-SMI was 46.2± 12.1 cm2/m2. Older age was the only risk factor associated with sarcopenia (p = 0.001). The overall survival at two years for the whole group was 65.2%. Sarcopenia and MELD score were independent predictors of OS at two years with HR of 7.6 (95% CI: 3.1– 18.7) and 2.2 (95% CI: 1.0– 4.8), respectively. Recurrence-free survival was 84.1% at two years. Recurrence was not affected by all factors, including sarcopenia.Conclusion: Sarcopenia is a surrogate predictor of overall survival at two years in HCC patients after RFA. Sarcopenia assessment might be an additional prognostic indicator with conventional biomarkers to optimize the selection criteria for receiving RFA for early-stage HCC.Keywords: sarcopenia, mortality, hepatocellular carcinoma, radiofrequency ablation

Ahmed Salman,1 Hossam El-Din Shaaban,2 Mohamed Salman,3 Sayed M Seif El Nasr,1 Ahmed Soliman,1 Abdoh Salem,4 Mohamed Tag El-Din,4 Hani Maurice Sabri Mikhail,3 Heba El Domiaty,5 Nesrin Abd Allah,6 Ghada MK GabAllah,7 Ahmed Youssef1 1Internal Medicine Department, Faculty of Medicine, Cairo University, Cairo, Egypt; 2Gastroenterology Department, National Hepatology and Tropical Medicine Research Institute, Cairo, Egypt; 3General Surgery Department, Faculty of Medicine, Cairo University, Cairo, Egypt; 4General Surgery Department, Faculty of Medicine, Al-Azhar University, Cairo, Egypt; 5Clinical Physiology Department, Faculty of Medicine, Menoufia University, Shebin El-Kom, Menoufia, Egypt; 6Anatomy and Embryology Department, Faculty of Medicine, Menoufia University, Shebin El-Kom, Menoufia, Egypt; 7Medical Biochemistry Department, Faculty of Medicine, Menoufia University, Shebin El-Kom, Menoufia, EgyptCorrespondence: Ahmed SalmanInternal Medicine Department, Faculty of Medicine, Cairo University, Cairo, EgyptTel +20 1000468664Email awea844@gmail.comPurpose: This study aimed to assess the potential changes of Growth differentiation factor 15 (GDF15) after laparoscopic sleeve gastrectomy (LSG) in morbidly obese patients.Methods: We conducted a prospective study on 68 patients who underwent LSG and 58 cases, who were enrolled as a control group, to whom conservative measures of weight loss were adopted. Both groups were followed for 12 months.Results: At the baseline, the serum GDF15 was comparable between LSG and conservative groups (409.93± 119 versus 385.8± 120.2 pg/mL, p =0.246). However, at 12 months after the operation, the serum GDF15 was significantly higher in the LSG than conservative groups (699.941 ± 193.5 versus 559 ± 159.7; p < 0.001). The degree of serum GDF15 increase was higher in the LSG group (290.01 ± 189.9 versus 173.14 ± 116.7; p < 0.001). The degree of serum GDF15 increase correlated negatively with the final BMI (r = − 0.352, p =0.001) and weight loss (r = − 0.793, p =0.001) at 12 months after the operation. The correlation analysis demonstrated that the initial GFD15 did not correlate with any baseline parameters. Multiple regression analysis of change in serum GDF15 showed a statistical significance of the weight loss after 12 months.Conclusion: The present work confirms the impact of successful weight loss on the circulating level of GDF15. Our study demonstrated that the circulating GDF15 increased significantly after LSG and it was correlated to the degree of weight loss.Keywords: bariatric surgery, laparoscopic sleeve gastrectomy, growth differentiation factor 15, appetite

Abstarct: Aim: Recently, increasing evidence showed that small-for-size syndrome (SFSS) is a multifactorial disease which is precipitated by various perioperative factors other than graft size. We conducted the current work to evaluate perioperative effectors, which can increase the risk of SFSS following adult living-donor liver transplantation (LDLT). Methods: This is a retrospective study on 110 adult cirrhotic cases (mean age of 48.4 ± 6.9 years old) who underwent adult LDLT. Most cases were males (89%). Cases were categorized into two groups based on the occurrence of SFSS. The groups were compared regarding preoperative (gender, age, comorbidities, baseline investigations), intraoperative (mean blood pressure and glucose; mean operation time; number of packed red cells, plasma, platelets, and cryoprecipitate units; time of cold and warm ischemia, and anhepatic phase; preclamping and post-reperfusion portal pressures), and postoperative factors (relevant investigations, hospital stay). Results: Postoperatively, 23 patients developed SFSS (20.9%). SFSS group had significantly lower preoperative graft recipient weight ratio (GRWR) (0.76 ± 0.1% versus 1.03 ± 0.15, respectively; p

Background: In recent years, the survival rate of laryngeal carcinoma patients has been demonstrating a decreasing trend from (57.1% to 51.9%) we retrospectively analyze the various prognostic factors in patients with advanced laryngeal cancer. To explore the best options across the continuum of care for patients.Patients and Methods: A retrospective analytic study evaluating prognostic factors in 110 patients with advanced laryngeal carcinoma. Selected prognostic factors includes age, gender, smoking, tumor subsite, TNM classification, clinical staging, thyroid cartilage invasion, treatment modality, surgical margins, Preoperative tracheostomy, postoperative fistula, associated comorbidities (chronic diseases).Results: All patients were followed up for at least 36 months, the survival rates 1, 2 and 3 years after the treatment were 91.8%, 81% and 68.1% respectively. The disease-free progression rates were 89%, 81% and 71.8% respectively.Conclusion: The increase in Age, Trans-glottic tumors, Thyroid cartilage invasion and Stage-IV AJCC; had an independent effect on increasing the probability of mortality occurrence

Purpose Epicardial fat thickness is an interesting parameter of early atherosclerosis. We prospectively assessed whether weight loss following laparoscopic sleeve gastrectomy (LSG) leads to a significant reduction in the epicardial fat thickness (EFT) and the correlation between the decline in the epicardial fat thickness with other clinical parameters. Methods A prospective analysis of 98 cases that were scheduled to undergo LSG and followed up for 12 months was conducted. EFT was assessed using two-dimensional (2 D) echocardiography. Results A total of 98 cases and 70 controls were enrolled. EFT demonstrated a significant reduction at follow-up in the whole group (median 8.9 (1.95) versus 7.65 (1.67) mm, respectively). The degree of reduction was higher in the LSG cohort compared to control cohort 1.3 (0.4) versus 1 (0.4), respectively; p

Background: We postulated that the preoperative correction of vitamin D levels can significantly reduce the incidence of hunger bone syndrome among patients undergoing parathyroidectomy for primary hyperparathyroidism. Methods: We performed a prospective, randomized, open-label study on 102 patients with primary hyperparathyroidism and coexisting vitamin D deficiency who were scheduled to undergo parathyroidectomy. Patients were divided into the following two groups: group I which included 52 patients who did not receive preoperative vitamin D supplementation; and group II which included 50 patients who received cholecalciferol 1000–2000 IU daily or 50000 IU weekly until they achieve vitamin D levels >20 ng/mL (group IIa = 25 patients) or vitamin D levels >30 ng/mL (group IIb = 25 patients). Results: The incidence of hunger bone syndrome in group IIb was lower than group I and group IIa (8% versus 16% versus 23%, respectively); however, this difference did not reach the level of statistical significance (p = 0.22). Patients with hunger bone syndrome were significantly younger and had higher serum phosphorus, alkaline phosphatase, magnesium, and bone mineral density at baseline than patients without hunger bone syndrome. On the other hand, patients with hunger bone syndrome had significantly lower 25-hydroxyvitamin D at baseline than patients without hunger bone syndrome (p = 0.001). The ROC curve showed that the baseline level of serum 25-hydroxyvitamin D was not an independent discriminator of hunger bone syndrome (area under curve = 0.21 (95% CI: 0.06–0.34); p = 0.011). Conclusions: Preoperative course of vitamin D supplements has no preventive role on the postoperative incidence of hunger bone syndrome among patients with primary hyperparathyroidism and coexisting vitamin D deficiency undergoing parathyroidectomy.

Background: Simeprevir is one of the recently discovered drugs for treating hepatitis C which is one of the major diseases across the globe. Objective: The present study involves the development of a new and unique High-Performance Liquid Chromatography (HPLC) method using fluorescence detection for the determination of simeprevir (SIM) in human plasma. Methods: Two methods of extractions were tested, protein precipitation using acetonitrile and liquidliquid extraction. A 25 mM dipotassium hydrogen orthophosphate (pH 7.0)/ACN (50/50; v/v), was used as mobile phase and C18 reversed phase column as the stationary phase. The chromatographic conditions were optimized and the concentration of simeprevir was determined by using the fluorescence detector. Cyclobenzaprine was used as an internal standard. Results: Recovery of the assay method based on protein precipitation was up to 100%. Intra-day and inter-day accuracies range from 92.30 to 107.80%, with Relative Standard Deviation (RSD) range 1.65-8.02%. The present method was successfully applied to a pharmacokinetic study where SIM was administered as a single dose of 150 mg SIM/capsule (Olysio®) to healthy individuals. Conclusion: This method exhibits high sensitivity with a low limit of quantification 10 ng mL-1, good selectivity using fluorescence detection, wide linear application range 10-3000 ng mL-1, good recovery and highly precise and validation results. The developed method can be applied in routine analysis for real samples.

BACKGROUND & AIM Bariatric surgery is a valid treatment option for persons with non-alcoholic fatty liver disease. This study prospectively examined the impact of laparoscopic sleeve gastrectomy (LSG) on liver histopathology, and blood levels of adiponectin, leptin, resistin, and pre-B cell enhancing factor/Nampt/visfatin. PATIENTS & METHODS In 81 patients with non-alcoholic fatty liver disease who underwent LSG, paired liver biopsies and blood specimens were obtained before and 18 months after LSG. Differences between preoperative and 18 months postoperative data were tested by paired Student's t-test or Wilcoxon rank test as appropriate. RESULTS At follow up, there was a significant improvement in biochemical markers for glucose homeostasis, including fasting glucose, HbA1c, insulin levels, and homeostatic model assessment index. Postoperative liver function tests, namely serum alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transpeptidase level, showed a significant improvement compared to before weight loss. The number of patients who had definite, borderline, or no non-alcoholic steatohepatitis was 43 (53%), 27 (33%), and 11 (14%), respectively, at baseline, and 9 (11%), 32 (40%), and 40 (49%) at 18-month post-surgery follow up. A significant reduction in steatosis, liver fibrosis, lobular inflammation, and hepatocyte ballooning was observed in the postoperative biopsies (P

Background and study aims: To evaluate the impact of intra- operatively measured portal vein pressure (PVP) on mortality in non-cirrhotic bilharzial patients undergoing splenectomy. Methods: The present study is a prospective study that was conducted in Egypt from April 2014 to April 2018. Adult patients with non-cirrhotic bilharziasis who were scheduled to undergo splenectomy were included. Studied cases were divided into a survival cohort and a non-survival cohort. The main objective was the correlation between the incidence of mortality and intraoperative PVP. Results: The present work comprised 130 cases with a mean age of 51.8 ± 6.4 years old. The in-hospital mortality rate was 22.3%, with sepsis as a major cause of death (37.9%). In term of the association between preoperative variables and mortality, survivors had statistically significant lower portal vein diameter (13.6 ± 1.8 versus 15.2 ± 1.8mm; p 14.5mmHg was an independent predictor of death and showed good diagnostic performance for the detection of early postoperative mortality.

There are insufficient data showing the impact of laparoscopic sleeve gastrectomy (LSG) on carotid intima-media thickness (CIMT). Therefore, in the current work, we investigated the improvement of metabolic syndrome and CIMT in patients with obesity after LSG. This study involved 120 consecutively selected Egyptian patients with a high cardiovascular risk who underwent LSG and were followed up for 12 months. CIMT declined from 0.95 ± 0.17 mm to 0.83 ± 0.12 (p < 0.001) after 12 months. In addition, the mean fasting blood glucose and fasting inulin level dropped significantly from 153.3 ± 63.6 to 108.8 ± 33.8 mg/dl and from 23.1 ± 7.1 mU/ml to 14.1 ± 6.4 respectively (p < 0.001). Furthermore, glycated hemoglobin (HbA1c) declined from 7.02 ± 1.7 to 5.5 ± 0.96 (p < 0.001). At the end of the follow-up period, metabolic parameters such as HOMA-IR, C-reactive protein (CRP), fibrinogen, total cholesterol, LDL cholesterol, triglycerides, AST, and ALT decreased significantly from their respective baselines (p value < 0.001). Moreover, the reduction in CIMT showed a strong positive correlation with the degree of weight loss at 6 months and 12 months of follow-up. LSG led to a substantial decrease in CIMT. Moreover, it significantly impacted cardiovascular risk factors such as obesity, hypertension, insulin resistance, lipid profile, and inflammatory markers.

Ahmed Salman,1 Mohamed Salman,2 Mohamed D Sarhan,2 Karim Maurice,2 Mohamed Tag El-Din,3 Ahmed Youssef,1 Reham Ahmed,1 Tarek Abouelregal,1 Hossam El-Din Shaaban,4 Ghada MK GabAllah,5 Mahmoud Gouda Omar1 1Internal Medicine Department, Faculty of Medicine, Cairo University, Cairo, Egypt; 2General Surgery Department, Faculty of Medicine, Cairo University, Cairo, Egypt; 3General Surgery Department, Faculty of Medicine, Al-Azhar University, Cairo, Egypt; 4Gastroenterology Department, National Hepatology and Tropical Medicine Research Institute, Cairo, Egypt; 5Medical Biochemistry Department, Faculty of Medicine, Menoufia University, Shibin Al Kawm, EgyptCorrespondence: Ahmed SalmanInternal Medicine Department, Faculty of Medicine, Cairo University, Cairo, 11311, EgyptTel +20 1000468664Email awea844@gmail.comIntroduction: Adipose tissues synthesize and secrete various proinflammatory and anti-inflammatory mediators, termed cytokines. This work aims to assess different serum and urinary cytokine levels before and 12 months after laparoscopic sleeve gastrectomy (LSG).Patients: This prospective study was performed on 61 obese non-diabetic patients who underwent LSG. All patients were followed up postoperatively at 12 months with the assessment of arterial blood pressure, microalbuminuria, urinary and serum levels of inflammatory cytokines (macrophage migration inhibitory factor “MIF,” monocyte chemotactic protein “MCP”-1, chemokine (C-C motif) ligand 15 (CCL-15), and CCL-18), in addition to serum creatinine, total cholesterol, and C-reactive protein (CRP).Results: Mean BMI showed decreased substantially from 44.78 ± 3.59 Kg/m2 to 34.56 ± 2.45. Systolic blood pressure decreased from 147.03 ± 16.89 mmHg to 128.82 ± 12.52 and diastolic blood pressure decreased from 90.51 ± 12.71 mmHg to 79.69 ± 10.39. At one-year of follow-up, there was statistically significant decrease of mean serum creatinine, total cholesterol, CRP, CCL-15, CCL-18, MIF/creatinine ratio, MCP-1/creatinine ratio, CCL-15/creatinine ratio, and CCL-18/creatinine ratio (P value < 0.001).Conclusion: Improvement of systemic and renal inflammatory states after LSG may positively affect obesity-related renal disease by steering the adipokine levels towards anti-inflammatory profiles.Keywords: laparoscopic sleeve gastrectomy, urinary cytokines

Post-endoscopic hemostasis treatment is not adequately addressed in high-risk patients on regular hemodialysis (HD) with emergency peptic ulcer bleeding. This study aimed to compare post-endoscopic high- versus low-dose proton pump inhibitors (PPIs) for peptic ulcer bleeding in patients undergoing regular HD. This prospective study comprised 200 patients on regular hemodialysis having emergency peptic ulcer bleeding confirmed at endoscopy and managed with endoscopic hemostasis. Half of the patients received high-dose intensive regimen and the other half received the standard regimen. Patients who were suspected to have recurrent bleeding underwent a second endoscopy for bleeding control. The primary outcome measure was rate of recurrent bleeding during period of hospitalization that was detected through second endoscopy. Rebleeding occurred in 32 patients ; 15 in the High-Dose Cohort and 17 in the Low-Dose Control (p = 0.700). No significant differences between the two dose cohorts regarding the time of rebleeding (p = 0.243), endoscopic hemostasis mode (p = 1.000), and need for surgery (p = 0.306). The high-dose regimen In-hospital mortality in high-dose group was 9.0% compared to 8.0% in the low-dose group (p = 0.800). Apart from the pre-hemostatic Forrest classification of ulcers, there were no significant differences between patients with re-bleeding ulcers (n=32) and those with non-rebleeding (n=168). Rebleeding was more common in class Ia, i.e. spurting bleeders (p < 0.001). Endoscopic hemostasis followed by the standard low-dose PPI regimen of 40 mg daily IV boluses is safe and effective option for bleeding peptic ulcers in the high-risk patients under regular hemodialysis.

Moringa oleifera is one of miracle tree and great interested medicinal plant which belongs to Moringaceae. It is widely used as a nutritive herb and possesses valuable pharmacological activities. In our study a rapid, sensitive and accurate HPLC method for qualitative and quantitative determination of gallic acid and rutin in two different solvent methanol and ethanol, extracts of Moringa oleifera leaves cultivated in Egypt was investigated. The separation was performed and validated by isocratic method utilizing C18 column with a mobile phase 10% (v/v) acetonitrile and 1.0% aqueous acetic acid mixture for gallic acid and 60% (v/v) methanol and 1.0% aqueous acetic acid mixture for rutin. Those bioactive components, gallic acid and rutin, were detected at 280 and 335 nm, respectively. The calibration graph was found to be linear in the concentration ranges 5.0-40.0 and 5.0-60.0 µg/mL for gallic acid and rutin, respectively. The higher concentrations of gallic acid were observed in the 50% methanolic and ethanolic extracts, while the higher concentrations of rutin were observed in the 100% methanolic and ethanolic extracts. Moreover, a successfully spectrophotometric quantification of the total phenolics and flavonoids content in the plant extract was achieved, where the equivalent amount to gallic acid in methanolic and ethanolic extracts and the equivalent amount to rutin in methanolic and ethanolic extracts were calculated.

Graphical abstract, This study investigated the elimination of Cr(VI) from aqueous solution utilizing a composite from magnetic nanoparticles (Fe3O4) capped with cetyltrimethylammonium bromide (CTAB). The structure of the prepared composite system was examined by Fourier Transform Infra Red Spectroscopy (FTIR), X-ray Diffractometry (XRD), and Transmission Electron Microscopy (TEM). Separation of the Fe3O4/CTAB composite from the wastewater can be achieved by application of an external magnetic field. Factors affecting the Cr(VI) expulsion from wastewater such as pH, competing ions, the dosage level of the nanoparticles, and contact time were studied. The results indicated that the maximum efficiency of the present system for removal of Cr(VI) (95.77%) was in acidic conditions (pH 4), contact time 12 h, and composite dosage of 12 mg/mL. The used Cr(VI) concentration was 100 mg/L. Considering results, the Fe3O4/CTAB system showed a high capability and selectivity for the treatment of water sullied with Cr(VI). This can recede the mutagenic and carcinogenic health risk caused by Cr(VI) water tainting.

TWO BACTERIAL strains were isolated by soil enrichment technique and identified as Lysinibacillus sphaericus DM-3 and Bacillus cereus DM-5. Biodegradation experiments were performed in carbon free-mineral salt media supplemented with 100 mg/L of dimethoate. The ability of bacterial strains to degrade the dimethoate was evaluated under various conditions such as pH range, temperature and different concentrations of dimethoate. The dimethoate residue was determined quantitatively by HPLC method and the degradation byproducts were identified by GC/MS technique. The results revealed that both bacterial strains can utilize dimethoate as a sole carbon source up to a concentration of 500 mg/L. The optimum temperature for both strains to degrade dimethoate was 28°C. L. sphaericus DM-3 and B. cereus DM-5 showed maximum growth in the presence of dimethoate at pH 6.0 and 7.0, respectively. L. sphaericus DM-3 could degrade 24% of dimethoate within 72 h, whereas the degradation percentage using B. cereus DM-5 was 17% after the same incubation period. The main byproducts from the degradation of dimethoate by L. sphaericus DM-3 and B. cereus DM-5 was namely O,O,S-trimethyl phosphorothioate. This study reports for the first time the efficient ability of L. sphaericus DM-3 and B. cereus DM-5 to degrade dimethoate, up to 500 mg/L, over a wide range of pH.

A chemically modified carbon paste electrode for chromium (III) based on the formation of ion-association complex of chromium with 5-ethyl-6-oxo-5-pentan-2-yl-sulfanyl-pyrimidin-4-olate (thiopental, THP) as electroactive ion-exchanger (Cr-THP) was prepared and investigated. The electrode has a linear dynamic range of 1.7 × 10−6–1.3 × 10−2 mol L−1, with a Nernstian slope of 19.6 ± 0.5 mV per decade and a detection limit of 9.0 × 10−7 mol L−1. It has a fast response time of

This paper provides a comprehensive overview of the actual knowledge on the atmospheric pollution sources, transport, transformation and levels in the East Mediterranean. It focuses both on the background atmosphere and on the similarities and differences between the urban areas that exhibited important urbanization the past years: the two megacities Istanbul, Cairo and the Athens extended area. Ground-based observations are combined with satellite data and atmospheric modeling. The overall evaluation pointed out that long and regional range transport of natural and anthropogenic pollution sources have about similar importance with local sources for the background air pollution levels in the area.

Two simple and highly sensitive spectrophotometric methods were developed for the quantitative determination of the drug sildenafil citrate (SC), Viagra, in pure form and in pharmaceutical formulations, through ion-associate formation reactions (method A) with mono-chromotropic acid azo dyes, chromotrope 2B (I) and chromotrope 2R (II) and ion-pair reactions (method B) with bi-chromotropic acid azo dyes, 3-phenylazo-6-o-carboxyphenylazo-chromotropic acid (III), bis-3,6-(o-hydroxyphenylazo)-chromotropic acid (IV), bis-3,6-(p-N,N-dimethylphenylazo)-chromotropic acid (V) and 3-phenylazo-6-o-hydroxyphenylazo-chromotorpic acid (VI). The reaction products, extractable in methylene chloride, were quantitatively measured at 540, 520, 540, 570, 600 and 575 nm using reagents, I–VI, respectively. The reaction conditions were studied and optimized. Beer's plots were linear in the concentration ranges 3.3–87.0, 3.3–96.0, 5.0–115.0, 2.5–125.0, 8.3–166.7 and 0.8–15.0 μg mL −1 with corresponding molar absorptivities 1.02 × 10 4 , 8.34 × 10 3 , 6.86 × 10 3 , 5.42 × 10 3 , 3.35 × 10 3 and 2.32 × 10 4 L mol −1 cm −1 using reagents I–VI, respectively. The limits of detection and Sandell's sensitivities were calculated. The methods were successfully applied to the analysis of commercial tablets (Vigoran) and the recovery study reveals that there is no interference from the common excipients that are present in tablets. Statistical comparison of the results was performed with regard to accuracy and precision using Student's t - and F -tests at 95% confidence level. There is no significant difference between the reported and proposed methods with regard to accuracy and precision.

Sodium tetraphenylborate and phosphotungstic acid were used as titrants for the conductimetric determination of phenylpropanolamine HCl (PPA.Cl), ranitidine HCl (Ra.Cl), hyoscyamine HBr (Hy.Br) and betaine HCl (Be.Cl) through ion-associate complex formation. The molar combining ratio and the solubility products of the formed ion-associates were studied and calculated. The suggested method has been applied to the determination of the mentioned drugs in their pure state and pharmaceutical preparations with mean recovery values of 97.71-102.97% and relative standard deviations 0.25-0.85%. The accuracy of the method is indicated by excellent recovery and low standard deviation. The results are compared with the pharmacopoeial or the official methods.

New phenylpropanolamine hydrochloride (PPA.Cl)-selective electrodes of the conventional polymer membrane type, based on incorporation of phenylpropanolamine–tetraphenylborate (PPA–TPB) ion-pair or phenylpropanolamine–phosphotungstate (PPA–PT) ion-associate in a poly(vinyl chloride) (PVC) membrane plasticized with dioctylphethalate (DOP) or dibutylphethalate (DBP), have been constructed. The electrodes were fully characterized in terms of the membrane composition, temperature, and pH. The electrodes were applied to the potentiometric determination of PPA.Cl in pure solutions and in pharmaceutical preparations under batch and flow injection conditions. The sensors showed fast, stable, and Nernstian slope over the concentration ranges 1.0×10 −5 to 8.91×10 −3 M and 10 −5 to 10 −2 M in the case of PPA–TPB applying batch and flow injection analysis (FIA), respectively, and 5.01×10 −6 to 1.25×10 −3 M and 10 −5 to 10 −2 M in the case of PPA–PT for batch and FIA systems, respectively. The electrodes exhibited good selectivity for PPA.Cl with respect to a large number of inorganic cations, sugars, amino acids, and components other than phenylpropanolamine of the mixed drugs. The effect of temperature on the electrodes was also studied.

Novel PVC membrane electrodes for the determination of betaine ion based on the formation of betaine-tetraphenylborate (Be-TPB) and betaine-phosphotungstate (Be-PT) ion-exchangers as electroactive materials are described. The sensors show a fast, stable, near Nernstian response for 6.92 x 10(-6) to 7.94 x 10(-3) M and 1.0 x 10(-4) to 1.0 x 10(-2) M betaine hydrochloride (Be.Cl) in case of Be-TPB electrode applying batch and flow injection analysis (FIA), respectively, and 2.95 x 10(-5) to 2.26 x 10(-3) M and 3.16 x 10(-5) to 1.0 x 10(-2) M in case of Be-PT electrode for batch and FIA electrodes, respectively, at 25 degrees C over the pH range of 3.5-10 with a cationic slope of 60.2 and 59.1 mV decade(-1) and a fast potential response of < or =15 s. The lower detection limits are 7.94 x 10(-6) and 3.18 x 10(-5) M Be.Cl for Be-TPB and Be-PT electrodes, respectively. Selectivity coefficient data for some common inorganic cations, sugars, amino acids and the components other than betaine, of the mixed drug investigated show negligible interference. The electrodes have been applied to the direct potentiometric determination of betaine hydrochloride in water and in a pharmaceutical preparation under batch and FIA conditions. Potentiometric titrations of Be.Cl with NaTPB and PTA as titrants were monitored with the developed betaine electrodes as an end point indicator electrode. The determination of Be.Cl shows an average recovery of 100.8% with mean relative standard deviation of 0.61%. The effect of temperature on the electrodes was also studied.

A simple titrimetric method is described for the determination of dothiepin hydrochloride. The method is based on titrating the cited drug with potassium salts of trioxalato-ferrate (III) (TOXFe), trioxalato-chromate (III) (TOXCr), trioxalatoaluminate (III) (TOXAI) and trioxalato-cobaltate (III) (TOXCo). The end point was located conductimetrically. The effect of solvent, molar ratio, reagent concentration and temperature were studied. Based on conductimetric measurements at 25 °C, the solubility, solubility product, free energy (ΔG) and entropy changes (ΔS) of the ion associates were calculated. Calculations of the enthalpy change (ΔH) are based on atomic absorption measurements of the solubility of the ion associates at different temperatures. The method allowed the determination of 6.63-29.87, 3.31-49.78, 9.95-49.78 and 3.31-33.19 mg of the studied drug using TOXFe, TOXCr, TOXAl and TOXCo, respectively. The method was further applied successfully to some dosage forms containing the cited drug, and the obtained results were compared favorably with those previously given by the official method.

Two sensitive spectrophotometric and atomic absorption spectrometric procedures have been developed for determination of cinchocaine hydrochloride (Cin.Cl) in pure form and in pharmaceutical formulation. The spectrophotometric method was based on formation of an insoluble colored ion-associate between the cited drug and tetrathiocyanatocobaltate (CoTC) or hexathiocyanatochromate (CrTC) which dissolved and extracted in an organic solvent. The optimal experimental conditions for quantitative extraction such as pH, concentration of the reagents and solvent were studied. Toluene and iso-butyl alcohol proved to be the most suitable solvents for quantitative extraction of Cin-CoTC and Cin-CrTC ion-associates with maximum absorbance at 620 and 555 nm, respectively. The optimum concentration ranges, molar absorptivities, Ringbom ranges and Sandell sensitivities were also evaluated. The atomic absorption spectrometric method is based on measuring of the excess cobalt or chromium in the aqueous solution, after precipitation of the drug, at 240.7 and 357.9 nm, respectively. Linear application ranges, characteristic masses and detection limits were 57.99-361.9, 50.40 and 4.22 microg ml(-1) of Cin.Cl, in case of CoTC, while 37.99-379.9, 18.94 and 0.81 microg ml(-1) in case of CrTC.