Comparative HPTLC study for simultaneous determination of ivabradine and metoprolol using UV and fluorescence detectors

New, simple, accurate, sensitive and validated high performance thin layer chromatographic (HPTLC) method coupled with UV absorbance mode and fluorescence (FL) detectors which were used for simultaneous determination of ivabradine (IVA) and metoprolol (MET) in their bulk and pharmaceutical dosage form using TLC silica 60 F254 plates and non-fluorescent TLC silica gel 60 plates. The developing system was chloroform: methanol: formic acid: ammonia (8.5:1.5:0.2:0.1, v/v). Desnitometric analysis in UV absorbance mode was set at λ = 275 nm. While, fluorescence mode was performed with excitation at 260 nm for quantitative simultaneous determination of IVA and MET using optical filter K320. The retention factors values were 0.45 ± 0.05 and 0.89 ± 0.01 of IVA and MET, respectively. UV absorbance mode, linearity was 50.0-600.0 ng/band for IVA and 50.0-900.0 ng/band for MET. For fluorescence mode, the linearity ranges were 18.0-400.0 ng/band and 50.0-550.0 ng/band for IVA and MET; respectively. ICH guidelines were followed in respect to linearity and range, accuracy, precision and selectivity, limit of detection (LOD), limit of quantitation (LOQ) and robustness. The analytical eco-scale, green analytical procedure index (GAPI) and analytical greenness metric tools were used to assess the suggested method. The quantitative proposed method results showed there was no statistically significant difference at 95% confidence when compared to the reported method of high performance liquid chromatography (HPLC).

Spectrofluorimetric and stability-indicating thin layer chromatographic methods for determination of cabergoline, a prolactin inhibitor in pharmaceuticals

Simple, Economic, and selective spectrofluorimetric and stability-indicating thin layer chromatographic (TLC) with fluorescence detection methods were developed for the determination of Cabergoline, a potent prolactin inhibitor, and long-acting dopamine receptor agonist, in bulk drug and pharmaceutical dosage forms based on its native fluorescence. Method A was based on measuring the fluorescence intensity at 338 nm after excitation at 280 nm. The measured fluorescence was directly proportional to the concentration of the drug over the range of 50.0-450.0 ng/mL with a limit of detection of 14.4 and a limit of quantification of 43.7 ng/mL. The TLC method (method B) was employed on TLC silica gel 60 F₂₅₄ aluminum sheets previously exposed to concentrated (30-34 %) hydrochloric acid vapor. Ethyl acetate: n-hexane: diethylamine system with a ratio of (10: 3: 1, v/v/v) developing system was used. The retention factor (R_f) of Cabergoline was 0.58 ± 0.03. Linearity was found to be in the range of 100.0-1500.0 ng/band. The LOD and LOQ were 25.4 and 76.9 ng/band, respectively. The methods were validated successfully according to ICH guidelines.

Two Epidemics and a Pandemic: The Collision of Prescription Drug Misuse and Racism during COVID-19

The present study investigated the relationship between perceived racial discrimination and prescription drug misuse (PDM) among Asian, Black, and Latinx Americans during the COVID-19 crisis. U.S. racial/ethnic minorities may have been uniquely affected by two national and one global pandemic: the opioid crisis, racism, and COVID-19. Opioid death rates increased among many groups prior to the pandemic. This country witnessed an increase in racialized acts against people of color across the spectrum in the spring and summer months of the world's COVID-19 outbreak. While studies have shown a clear link between perceived racial discrimination and substance abuse outside of the global pandemic, no identified studies have done so against the backdrop of a global health pandemic. Separate hierarchical regressions revealed a significant association between perceived racial discrimination and PDM for Black Americans, Asian Americans, and Latinx individuals. Findings build on the scant literature on PDM in diverse samples and establish a relationship between perceived racial discrimination and PDM, as previously identified for other abused substances. Future post-pandemic substance misuse interventions should consider the influence of perceived racial discrimination as they help individuals recover from the aftermath of this stressful trifecta.

Sensitive and validated TLC densitometry method coupled with fluorescence detection for quantitative determination of the newly co-formulated drugs, celecoxib and amlodipine besylate in tablet dosage form

New, sensitive, rapid, cost-effective, and validated stability-indicating thin layer chromatographic (TLC) method coupled with fluorescence (FL) detection was developed for the quantitative analysis of celecoxib (CEL) and amlodipine besylate (AMLO) in their laboratory prepared binary mixture using the non-fluorescent TLC silica gel 60 plates. Ethyl acetate: diethylamine: 1-propanol (9:1:0.2, V/V) was used as a developing system. The retention factor (Rf) for each drug was 0.80 ± 0.03 and 0.44 ± 0.01 for CEL and AMLO, respectively. The plates were excited at 264 nm for the simultaneous FL measurement of CEL and AMLO, the calibration curves were linear over a concentration ranges of 30.0–300.0 ng/band and 15.0–150.0 ng/band with mean percentage recoveries of 99.80 ± 0.85 and 99.80 ± 0.77 For CEL and AMLO, respectively. The developed method was applied for the stability studies of the cited drugs in their laboratory prepared binary mixture and the forced degradation products were determined when present in presence of the pure drugs so the method can be considered as a stability-indicating one and it was validated as per ICH guidelines and proved to be accurate and precise.

MicroRNAs and microbiota: Is there a cross talk?

MicroRNAs (miRNAs) are a form of single-stranded RNA molecules with a length that varies between 18 and 23 nucleotides and which are synthesized in the nucleus but function in the cytoplasm. miRNAs function endogenously and bind to complementary sequences in either the coding regions or the 3' untranslated regions (UTRs) of target messenger RNAs (mRNAs). This indicates that miRNAs operate in a post-transcriptional manner. miRNAs play essential roles in various biological events, and have thus been found extracellularly in different body fluids such as saliva, urine and plasma. miRNAs are distinguished in the gut mainly by examining content from intestines and feces. The gastrointestinal tract is infested with a variety of microorganisms that are initially inherited from the mother; however, those microorganisms develop as a result of changes in dietary intakes and environmental factors. The gut microbiota are therefore shaped differently in different individuals due to several contributing factors such as genetics, diet and state of disease, and have a great impact on the host during phases of disease and homeostasis.

OP0018 A MULTICENTER RANDOMIZED STUDY IN EARLY RHEUMATOID ARTHRITIS TO COMPARE ACTIVE CONVENTIONAL THERAPY VERSUS THREE BIOLOGICAL TREATMENTS: 24 WEEK EFFICACY RESULTS OF THE NORD-STAR TRIAL

Background:

The optimal first-line treatment of patients (pts) with early rheumatoid arthritis (RA) is yet to be established.

Objectives:

The primary aim was to assess and compare the proportion of pts who achieved remission with active conventional therapy (ACT) and with three different biologic therapies after 24 wks. Secondary aims were to assess and compare other efficacy measures.

Methods:

The investigator-initiated NORD-STAR trial (NCT01491815) was conducted in the Nordic countries and Netherlands. In this multicenter, randomized, open-label, blinded-assessor study pts with treatment-naïve, early RA with DAS28>3.2, and positive RF or ACPA, or CRP >10mg/L were randomized 1:1:1:1. Methotrexate (25 mg/week after one month) was combined with: 1) (ACT): oral prednisolone (tapered quickly);or: sulphasalazine, hydroxychloroquine and mandatory intra-articular (IA) glucocorticoid (GC) injections in swollen joints <wk 20; 2) certolizumab 200 mg EOW SC (CZP); 3) abatacept 125 mg/wk SC (ABA); tocilizumab 162 mg/wk SC (TCZ). IA GC was allowed in all arms <wk 20. Primary outcome was clinical disease activity index remission (CDAI≤2.8) at wk 24. Secondary outcomes included CDAI remission over time and other remission criteria. Dichotomous outcomes were analyzed by adjusted logistic regression with non-responder imputation (NRI). Non-inferiority analyses had a pre-specified margin of 15%.

Results:

812 pts were randomized. Age was 54.3±14.7 yrs (mean±SD), 31.2% were male, DAS28 5.0±1.1, 74.9% were RF and 81.9% ACPA positive. Fig 1 shows the adjusted CDAI remission rates over time with 95% CI. Table shows crude remission and response rates and absolute differences in adjusted remission and response rates (superiority analysis). Differences in remission and response rates with CZP and TCZ, but not with ABA, remained within the pre-defined non-inferiority margin versus ACT, Fig 2.

Figure 1.

CDAI remission over time (adj. estimates with 95% CI)

Figure 2.

Non-inferiority analysis of protocol population. Estimated differences in CDAI remission rates between Arm 1 (active conventional therapy) and Arms 2, 3, and 4 (biologic arms) as reference with 95% confidence intervals, adjusted for gender, ACPA status, country, age, body-mass index and baseline DAS28-CRP. ABA, abatacept; CZP, certolizumab-pegol; MTX, methotrexate; TCZ, tocilizumab.

Conclusion:

High remission rates were found across all four treatment arms at 24 wks. Higher CDAI remission rate was observed for ABA versus ACT (+9%) and for CZP (+4%), but not for TCZ (-1%). With the predefined 15% margin, ACT was non-inferior to CZP and TCZ, but not to ABA. This underscores the efficacy of active conventional therapy based on MTX combined with glucocorticoids and may guide future treatment strategies for early RA.

Table.

Primary and key secondary outcomes at 24 weeks (ITT)

Active conventional therapy (ACT)Certolizumab+MTXAbatacept+MTXTocilizumab+MTXNo of pts (ITT)200203204188§Crude remission and response ratesCDAI remission42.0%47.8%52.5%41.0%ACR/EULAR Boolean remission34.0%38.4%37.3%31.4%DAS28 remission63.5%68.5%69.6%63.3%SDAI remission41.5%49.8%51.5%42.6%EULAR good response71.5%76.9%79.9%71.3%Difference (95% CI) in rates with Arm 1 as reference (adjusted)CDAI remissionRef4% (-5 to 13%)9% (0.1 to 19%)-1% (-10 to 9%)ACR/EULAR Boolean remissionRef4% (-6 to 13%)5% (-5 to 14%)-4% (-13 to 6%)DAS28 remissionRef3% (-6 to 11%)5% (-4 to 13%)-1% (-10 to 8%)SDAI remissionRef6% (-3 to 18%)9% (-0.3 to 18%)1% (-8 to 11%)EULAR good responseRef4% (-4 to 14%)8% (-2 to 18%)0.4% (-10 to 11%)

§17 patients allocated to Tocilizumab did not receive it due to its unavailability and were excluded from ITT.

Acknowledgments:

Manufacturers provided CZP and ABA.

Disclosure of Interests:

Merete L. Hetland Grant/research support from: BMS, MSD, AbbVie, Roche, Novartis, Biogen and Pfizer, Consultant of: Eli Lilly, Speakers bureau: Orion Pharma, Biogen, Pfizer, CellTrion, Merck and Samsung Bioepis, Espen A Haavardsholm Grant/research support from: AbbVie, UCB Pharma, Pfizer Inc, MSD Norway, Roche Norway, Consultant of: Pfizer, AbbVie, Janssen-Cilag, Gilead, UCB Pharma, Celgene, Lilly, Paid instructor for: UCB Pharma, Speakers bureau: Pfizer, AbbVie, UCB Pharma, Celgene, Lilly, Roche, MSD, Anna Rudin Consultant of: Astra/Zeneca, Dan Nordström Consultant of: Abbvie, Celgene, Lilly, Novartis, Pfizer, Roche and UCB., Speakers bureau: Abbvie, Celgene, Lilly, Novartis, Pfizer, Roche and UCB., Michael Nurmohamed Grant/research support from: Not related to this research, Consultant of: Not related to this research, Speakers bureau: Not related to this research, Björn Gudbjornsson Speakers bureau: Novartis and Amgen, Jon Lampa Speakers bureau: Pfizer, Janssen, Novartis, Kim Hørslev-Petersen: None declared, Till Uhlig Consultant of: Lilly, Pfizer, Speakers bureau: Grünenthal, Novartis, Gerdur Gröndal: None declared, Mikkel Ǿstergaard Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Merck, and Novartis, Consultant of: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Marte Heiberg: None declared, Jos Twisk: None declared, Simon Krabbe: None declared, Kristina Lend: None declared, Inge Olsen: None declared, Joakim Lindqvist: None declared, Anna-Karin H Ekwall Consultant of: AbbVie, Pfizer, Kathrine L. Grøn Grant/research support from: BMS, Meliha C Kapetanovic: None declared, Francesca Faustini: None declared, Riitta Tuompo: None declared, Tove Lorenzen: None declared, Giovanni Cagnotto: None declared, Eva Baecklund: None declared, Oliver Hendricks Grant/research support from: Pfizer, MSD, Daisy Vedder: None declared, Tuulikki Sokka-Isler: None declared, Tomas Husmark: None declared, Maud-Kristine A Ljosa: None declared, Eli Brodin: None declared, Torkell Ellingsen: None declared, Annika Soderbergh: None declared, Milad Rizk Speakers bureau: AbbVie, Åsa Reckner: None declared, Per Larsson: None declared, Line Uhrenholt Speakers bureau: Abbvie, Eli Lilly and Novartis (not related to the submitted work), Søren Andreas Just: None declared, David Stevens: None declared, Trine Bay Laurberg Consultant of: UCB Pharma (Advisory Board), Gunnstein Bakland Consultant of: Novartis, UCB, Ronald van Vollenhoven Grant/research support from: BMS, GSK, Lilly, UCB, Pfizer, Roche, Consultant of: AbbVie, AstraZeneca, Biogen, Biotest, Celgene, Gilead, Janssen, Pfizer, Servier, UCB, Speakers bureau: AbbVie, Pfizer, UCB

Patisiran for the treatment of patients with familial amyloid polyneuropathy

Onpattro, also commonly known as patisiran, is a small interfering RNA (siRNA) molecule packaged within a lipid nanoparticle and is transported into the cell to target transthyretin gene (TTR) messenger mRNA (mRNA) by attaching to its complementary sequence. The target mRNA is degraded and both mutant and wild-type amyloid transthyretin (ATTR) protein production becomes suppressed. This drug was developed by Alnylam Pharmaceuticals to treat a rare disease called hereditary ATTR (hATTR) amyloidosis. This disease develops as a result of the deposition of toxic aggregates of misfolded TTR protein, and is progressive causing the affected individual to be bed bound and to eventually die if left untreated. However, variable expressivity and incomplete penetrance cause carriers of TTR gene variants to be asymptomatic for a prolonged time. The heterogeneity of symptoms makes correct diagnosis of the disease difficult, therefore management of symptoms and proper treatment are delayed as a result. However, certain TTR variants are found in endemic or cluster regions, which facilitates their detection. In this review paper, different aspects of the drug are discussed in detail, including its preclinical and clinical studies, as well as its pharmacokinetic properties along with drug interactions leading to its approval by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA).

Micro-CT evaluation of sonically and ultrasonically activated irrigation on the removal of hard-tissue debris from isthmus-containing mesial root canal systems of mandibular molars

AIM

To evaluate the efficacy of sonically and ultrasonically activated irrigation on removal of accumulated hard-tissue debris (AHTD) in mesial root canal systems of mandibular molars using micro-computed tomographic (micro-CT) analysis.

METHODOLOGY

Forty mesial roots of mandibular molars with two independent canals joined apically by an isthmus (Vertucci type II) were selected. The root canals were instrumented using Reciproc R25 instruments, and specimens were scanned at a resolution of 10.5 μm. Subsequently, n = 10 roots were assigned to each of the four final irrigation groups such that the group means and variances were almost identical: sonically activated irrigation with EndoActivator (EA) or EDDY (ED), ultrasonically activated irrigation (UAI) and manual irrigation without activation (MI). The final irrigation procedures were performed using a total of 5 mL 1% NaOCl and 5 mL 15% EDTA per canal over 5 min with activation time of 4 × 20 s. Reconstructed data sets were coregistered, and the mean percentage reduction of AHTD after final irrigation was compared statistically between groups using analysis of variance at a significance level set at 5%.

RESULTS

A significant reduction of AHTD was achieved after final irrigation in all groups (P < 0.05), ranging from 44.1% to 66.8%. The vol% of debris after irrigation was 3.7 ± 1.9% for EA, 3.3 ± 2.3% for ED, 2.1 ± 1.6% for UAI and 4.4 ± 2.3% for MI, with no significant difference between groups (P > 0.05).

CONCLUSIONS

None of the final irrigation protocols completely removed AHTD from mesial root canal systems in extracted human mandibular molars. Sonically and ultrasonically activated irrigation performed no better compared to manual irrigation.

Efficacy of the ProTaper retreatment system in removing Thermafil, GuttaCore or vertically compacted gutta-percha from curved root canals assessed by micro-CT

AIM

To evaluate ex vivo the efficacy of ProTaper Universal Retreatment files (Dentsply Sirona, Ballaigues, Switzerland) in removing Thermafil, GuttaCore (both Dentsply Sirona) or vertically compacted gutta-percha from curved root canals using micro-CT.

METHODOLOGY

Sixty curved molar roots with the same mean canal curvatures and radii in two directions were prepared using ProFile instruments (Dentsply Sirona) to size 30 with .04 taper and obturated with either Thermafil, GuttaCore or vertically compacted gutta-percha and AH Plus (n = 20). Specimens were retreated using the ProTaper Universal Retreatment files D1, D2 and D3 to working length, and root canal preparation was completed with ProTaper Next (Dentsply Sirona) to size ×4. Percentages of residual filling material and dentine removal were assessed using micro-CT imaging. Working time and procedural errors were recorded. Statistical analysis was performed using Kruskal-Wallis and Wilcoxon tests.

RESULTS

No significant differences between carrier-based and warm vertical compaction regarding residual filling material (14.2-19.3%) and dentine removal (2.7-3.2 mm³ ) were detected (P > 0.05). Time to reach working length was significantly faster for canals filled with GuttaCore than that observed for Thermafil and warm vertical compaction (P < 0.05). Five lateral perforations with the D3 file occurred during retreatment, one in the Thermafil and four in the vertical compaction group.

CONCLUSIONS

Remaining filling material and dentine removal were similar for all canal filling techniques. Regaining working length was significantly faster for GuttaCore compared with Thermafil and vertically compacted gutta-percha. Procedural errors occurred during retreatment of severely curved root canals with the ProTaper Universal Retreatment files in 5 of 60 canals (8%).

Network geometry of evidence from randomised controlled trials addressing donor selection and source of haematopoietic progenitor cells used in allogeneic transplantation: a systematic scoping review

BACKGROUND AND METHODS

A scoping review of randomised controlled trials (RCTs) addressing source of cells and choice of donor for allogeneic haematopoietic cell transplantation (HCT) was performed to create a network of best evidence that allows us to identify new potential indirect comparisons for the strategic development of future studies that connect to the existing evidence network.

RESULTS

A total of 19 eligible RCTs (2589 total patients) were identified. Nine studies (1566 patients) compared clinical outcomes following the use of peripheral blood progenitor cells (PBPCs) with bone marrow (BM) from matched related donors (eight studies) or matched unrelated donors (one study). The remaining studies compared BM or PBPCs with various methods of BM stimulation or manipulation (six studies), compared different methods of surface molecule-based selection and/or depletion of grafts (two studies) or compared the optimal number of units for paediatric cord blood transplantation (two studies). No published RCTs compared different types of donors. The geometry of the evidence network was analysed to identify opportunities for potential novel indirect comparisons and to identify opportunities to expand the network. Few indirect comparisons are currently feasible due to small sample size and heterogeneity in patient diagnoses and demographics between treatment nodes in the network.

CONCLUSION

More RCTs that enrol greater numbers of similar patients are needed to leverage the current evidence network concerning donor choice and source of cells used in allogeneic HCT.

Injection laryngoplasty through a transoral approach using the Guedel oral airway

Injection laryngoplasty has gained popularity as a treatment modality for glottal insufficiency. Several approaches have been described, specifically transcutaneous, transoral and transnasal. The authors describe a novel technique performed successfully on three subjects, namely endoscopic injection laryngoplasty using the modified Guedel oral airway. There was marked improvement in dysphonia, maximum phonation time and closed quotient in all three subjects with a decrease in the Voice Handicap Index-10 score. This new approach is a viable approach for the treatment of glottal insufficiency.

Influence of Linker Length Variations on the Biomass-Degrading Performance of Heat-Active Enzyme Chimeras

Plant cell walls are composed of complex polysaccharides such as cellulose and hemicellulose. In order to efficiently hydrolyze cellulose, the synergistic action of several cellulases is required. Some anaerobic cellulolytic bacteria form multienzyme complexes, namely cellulosomes, while other microorganisms produce a portfolio of diverse enzymes that work in synergistic fashion. Molecular biological methods can mimic such effects through the generation of artificial bi- or multifunctional fusion enzymes. Endoglucanase and β-glucosidase from extremely thermophilic anaerobic bacteria Fervidobacterium gondwanense and Fervidobacterium islandicum, respectively, were fused end-to-end in an approach to optimize polysaccharide degradation. Both enzymes are optimally active at 90 °C and pH 6.0-7.0 representing excellent candidates for fusion experiments. The direct linkage of both enzymes led to an increased activity toward the substrate specific for β-glucosidase, but to a decreased activity of endoglucanase. However, these enzyme chimeras were superior over 1:1 mixtures of individual enzymes, because combined activities resulted in a higher final product yield. Therefore, such fusion enzymes exhibit promising features for application in industrial bioethanol production processes.

Fast sorption measurements of volatile organic compounds on building materials: Part 1 - Methodology developed for field applications

A Proton Transfer Reaction-Mass Spectrometer (PTR-MS) has been coupled to the outlet of a Field and Laboratory Emission Cell (FLEC), to measure volatile organic compounds (VOC) concentration during a sorption experiments (Rizk et al., this issue) [1]. The limits of detection of the PTR-MS for three VOCs are presented for different time resolution (2, 10 and 20 s). The mass transfer coefficient was calculated in the FLEC cavity for the different flow rates. The concentration profile obtained from a sorption experiment performed on a gypsum board and a vinyl flooring are also presented in comparison with the profile obtained for a Pyrex glass used as a material that do not present any sorption behavior (no sink). Finally, the correlation between the concentration of VOCs adsorbed on the surface of the gypsum board at equilibrium (C_se) and the concentration of VOCs C_e measured in the gas phase at equilibrium is presented for benzene, C8 aromatics and toluene.

Comparative in vivo antioxidant levels in Schistosoma mansoni infected mice treated with praziquantel or the essential oil of Melaleuca armillaris leaves

Plant extracts are continuously investigated for their extensive inclusion of biologically active constituents that exert therapeutic activities against many diseases. The aim of this study was to assess the antioxidant/anti-schistosomal activities of the essential oil of the fresh leaves of Melaleuca armillaris (M. armillaris) compared to Praziquantel (PZQ) on normal and Schistosoma mansoni-infected mice. The oil was isolated by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS). The oil was rich in 1,8-cineole (33.93%), terpinen-4-ol (18.79%), limonene (10.37%) and B-pinene (6.59%). M. armillaris oil (150 mg kg(-1), orally) was administered from the second week post infection twice per week for six weeks. PZQ (500 mg kg(-1), orally) was administered for two successive days 8 weeks post infection and mice sacrificed one week later. Total protein, Malondialdehyde (MDA), Glutathione (GSH), vitamins C and E, the antioxidant enzymes catalase and superoxide dismutase, as well as liver weights and liver/body weight were determined in the liver tissues. Results showed that, both treatments significantly ameliorated the disturbed levels ofGSH and MDA in infected mice. Both vitamins were significantly elevated after treatment with the oil while a significant increase in catalase accompanied by a pronounced decrease in SOD were obtained after treatment with PZQ. Both treatments markedly improved liver and body weights in infected mice compared to the infected-untreated ones. In conclusion, natural plant sources may be used as promising alternative agents to chemical drugs for schistosomiasis treatment, since the latter may result in drug-induced resistance arising from repeated use.

Capturing patient reported outcomes and quality of life in routine clinical practice: ready for prime time?

AIM

Aim of the present study was to assess the feasibility of using internet-tablets to capture patient reported outcomes (PRO) questionnaire in a busy gastroenterology clinic, and determine predictors of questionnaire completion. PRO and quality of life instruments are extensively used to estimate the burden of disease and as end-points in clinical trials. However, their collection by paper can be costly, prone to human errors, and inefficient. We hypothesized that the majority of patients, irrespective of age, gender or ethnicity, will be able to complete PRO questionnaires on Internet tablets in a timely manner with good levels of satisfaction.

METHODS

Internet-enabled tablets were used to collect PRO, and summative scores of quality of life provided to physicians. Predictors of completion were first assessed univariately and then by multivariate analysis using automated stepwise selection method on 1,000 bootstrap samples. Patient satisfaction was assessed using 5 item Likert-like scale.

RESULTS

During the 12 week period, 1625 patient visits (mean age 49.8 ± 14.3 years, females 55.2% and Whites 82.5%) entered PRO data into tablets, of which 1396 (85.9%) visits had complete response. Average completion time of PRO questionnaire was less than 10 minutes (9.3 minutes ± 7.0). Majority of the patients found tablets easy to use (69.7%) and preferred it over paper-based questionnaires (70.8%). Multivariate analysis showed that subjects who were white Caucasians (odds ratio [OR] 1.9; P=0.004), had higher Cleveland Clinic Global Quality of Life (OR 2.2; P=0.027), or had either IBD or liver disease, were more likely to complete questionnaire (OR 4.0; P=0.001).

CONCLUSION

Collection of PROs in gastroenterology clinics using internet-tablets is feasible without any additional overhead, and with good levels of patient satisfaction and completion rates.

Development and Validation of Spectrofluorimetric Method for Determination of Biotin in Bulk and Pharmaceutical Preparations via its Oxidation with Cerium (IV)

A simple and sensitive spectrofluorimetric method was developed for the determination of biotin in pure form and in pharmaceutical preparations. The proposed method is based on the oxidation of the drug with cerium (IV) ammonium sulfate in acidic medium. The fluorescence of the produced Cerium (III) was measured at 365 nm after excitation at 255 nm. The different experimental parameters affecting the development and stability of the reaction were carefully studied and optimized. The method is applicable over the concentration range of 30-120 ng/mL with correlation coefficient of 0.9998. The detection limit (LOD) of biotin was 2.41 ng/mL while quantitation limit (LOQ) was 7.29 ng/mL. The proposed procedure was successfully applied for the determination of biotin in pharmaceutical preparations with mean recoveries of 99.55 ± 0.83 and 101.67 ± 1.53 for biotin ampoules and capsules, respectively. The results obtained were in good agreement with those obtained using the official method.

Second derivative synchronous fluorescence spectroscopy for the simultaneous determination of chlorzoxazone and Ibuprofen in pharmaceutical preparations and biological fluids

A rapid, simple and highly sensitive second derivative synchronous fluorometric method has been developed for the simultaneous analysis of binary mixture of chlorzoxazone (CLZ) and ibuprofen (IP). The method is based upon measurement of the synchronous fluorescence intensity of these drugs at Δλ=60 nm in methanol. The different experimental parameters affecting the fluorescence of the two drugs were carefully studied and optimized. The fluorescence-concentration plots were rectilinear over the range of 0.2-4 μg/mL and 0.1-1.6 μg/mL for CLZ and IP, respectively with lower detection limits (LOD) of 0.028 and 8.3 × 10(-3) μg/mL and quantification limits (LOQ) of 0.086 and 0.03 μg/mL for CLZ and IP, respectively. The proposed method was successfully applied for the determination of the two compounds in synthetic mixtures and in commercial capsules. The high sensitivity attained by the proposed method allowed the determination of both drugs and real human plasma samples. The mean % recoveries in real human plasma (n=3) were 87.69 ± 6.15 and 92.57 ± 4.39 for each of CLZ and IP respectively.

Kinetic spectrophotometric determination of biotin in pharmaceutical preparations

A simple accurate kinetic spectrophotometric method was developed for the determination of biotin in pure form and pharmaceutical preparations. The proposed method is based on a catalytic acceleration of biotin on the reaction between sodium azide and tri-iodide in an aqueous solution. Concentration range of 4-16 μg/mL for biotin was determined by measuring the decrease in the absorbance of tri-iodide at 348 nm by a fixed time method. The decrease in absorbance after 14 min from the initiation of the reaction was markedly correlated to the concentration with correlation coefficient of 0.9999. The detection limit (LOD) of biotin was 0.18 μg/mL while quantitation limit (LOQ) was 0.54 μg/mL. The percentage recovery of the spiked samples was 100.08 ± 0.761. The proposed procedure was successfully applied for the determination of biotin in its pharmaceutical preparations with mean recoveries of 101.17 ± 2.05 and 97.87 ± 1.50 for biotin ampoules and capsules, respectively. The results obtained were in good agreement with those obtained using official method.

Oxidative hemolysis of erythrocytes induced by various vitamins

Hemolytic effect of some water-soluble vitamins (niacin B5, pyridoxine B6, thiamine B1 and ascorbic and acid C) on erythrocytes was studied spectrophotometrically at relatively high concentration. The oxidation mechanism of hemoglobin was the same for the used vitamins. Vitamin C was the strongest hemolytic agent in comparison with the other vitamins, while vitamin B1 is the weakest one. The results were confirmed by studying the variation in conductivity of erythrocytes with temperature in the range 20-40°C for the used vitamins at a concentration of 2 mM and after two hours from adding each vitamin to the erythrocytes suspension. The conductivity measurements show that the conductivity for the used vitamins is lower than that for control (without adding vitamin) due to hemoglobin oxidation, also may be due to the electrical reorganization of the erythrocyte membrane after the interaction of the used vitamin with it. The obtained results insure the oxidizing effect of the used vitamins on hemoglobin and consequently their hemolytic effect on erythrocytes.

Evaluation of tumour markers in molar pregnancy

METHODS

Circulating CA 125, CA 19-9, CA 15-3 and carcinoembryonic antigen (CEA) levels were studied in sixty patients with hydatidiform mole and in twenty normal pregnant women of a corresponding duration of pregnancy.

DISCUSSION

Serum levels of CA 125, CA 15-3 and CEA are not affected by molar pregnancy. The mean level of CA 19-9 in maternal serum is significantly lower in cases of molar pregnancy when compared with cases of normal pregnancy. The amnion cell origin of CA 19-9 could explain the statistically significant difference between cases of therapeutic abortion and cases of HM (complete HM lacks amniotic membrane).

Polarographic determination of flubendazole in spiked human urine and plasma

The voltammetric behavior of flubendazole was studied using direct current (DCt), differential pulse (DPP) and alternating current (ACt) polarography. The drug manifests a cathodic wave in 20% v/v formic acid solution. The wave was characterized as being irreversible, diffusion-controlled with limited adsorption properties. The diffusion current-concentration relationship was found to be rectilinear over the range 3.2-14.4 microg/ml and 0.1 to 12.8 microg/ml, using DCt and DPP modes, respectively, with minimum detectability of 0.161 microg/ml (5.14 x 10(-7) M) and 0.0.057 microg/ml (1.82 x 10(-8) M) using DCt and DPP modes, respectively. Furthermore, the proposed method was applied to the in-vitro determination of flubendazole in spiked human urine and plasma adopting the DPP technique. The percentage recoveries were 100.20+/-0.62 and 97.42+/-0.95, respectively.

A peripheral nerve stimulator for nerve location controlled by the scrubbed anaesthetist

This newly designed peripheral nerve stimulator allows the scrubbed anaesthetist performing a nerve block to adjust the electrical current output needed for localisation of the target nerve without the need for an assistant.

Voltammetric analysis of trazodone HCl in pharmaceuticals and biological fluids

The voltammetric behavior of trazodone (TRZ) HCl was studied using direct current (DC(t)), differential pulse (DPP) and alternating current (AC(t)) polarography. The drug manifests cathodic waves over the pH range of 10-14. The waves were characterized as being irreversible, diffusion-controlled with limited adsorption properties. At pH 10, the diffusion current-concentration relationship was found to be rectilinear over the range 4-32 and 0.8-24 microg ml(-1) using DC(t) and DPP modes, respectively, with minimum detectability (S/N=2) of 0.104 microg ml(-1) (2.45 x 10(-6) M) and 0.314 microg ml(-1) (7.397 x 10(-6) M) using the DPP and DC(t) modes, respectively. The diffusion-current constant (I(d)) is 4.31+/-0.02 (n=6). The proposed method was successfully applied to the determination of the studied compound either in pure form or in formulations. The results obtained were favorably compared with those given using a reference method. Furthermore, the proposed method was applied to the determination of TRZ in spiked human urine and plasma adopting the DPP technique. No prior extraction step is needed in case of urine. The percentage recoveries were 98.43+/-0.79 and 97.44+/-0.705 (n=4) in spiked human urine and plasma, respectively. A pathway for the electrode reaction was postulated.