777 research outputs found

    Spectrophotometric Determination of Certain Antiepileptic's in Tablets Using Vanillin Reagent

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    A selective and new spectrophotometric method is described for determination of three antiepileptic drugs; namely lamotrigine (LAM), gabapentin (GAB), and oxcarbazepine (OXC) in drug substances and in drug products using vanillin reagent as the chromogenic agent. The method is based on a coupling reaction between the cited drugs and vanillin reagent in acidic condition. Under optimized conditions, the yellow colored products were measured at 405, 396, and 400 nm respectively. Beer’s law was obeyed at (0.4 – 10), (0.1-10), and (0.5-11) μg/mL, and  the calculated molar absorptivity values are 2.52 x 104, 1.74 x 104, and 2.54 x 104 L/mol/cm for LAM, GAB, and OXC respectively. Sandell sensitivity, the limit of detection (LOD) and limit of quantification (LOQ) were calculated. No interference was observed from common additives found in drug products. The presented method was validated according to ICH guidelines. Statistical comparison of the results was performed using Student's t-test and F-ratio at 95% confidence level, and there was no significant difference between the reference and proposed method with regard to accuracy and precision. The method offers the advantages of rapidity, simplicity and sensitivity and low cost and can be easily applied to resource poor settings without the need for expensive instrumentation and reagents

    Cathepsin b: a potential prognostic marker for inflammatory breast cancer

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    <p>Abstract</p> <p>Background</p> <p>Inflammatory breast cancer (IBC) is the most aggressive form of breast cancer. In non-IBC, the cysteine protease cathepsin B (CTSB) is known to be involved in cancer progression and invasion; however, very little is known about its role in IBC.</p> <p>Methods</p> <p>In this study, we enrolled 23 IBC and 27 non-IBC patients. All patient tissues used for analysis were from untreated patients. Using immunohistochemistry and immunoblotting, we assessed the levels of expression of CTSB in IBC versus non-IBC patient tissues. Previously, we found that CTSB is localized to caveolar membrane microdomains in cancer cell lines including IBC, and therefore, we also examined the expression of caveolin-1 (cav-1), a structural protein of caveolae in IBC versus non-IBC tissues. In addition, we tested the correlation between the expression of CTSB and cav-1 and the number of positive metastatic lymph nodes in both patient groups.</p> <p>Results</p> <p>Our results revealed that CTSB and cav-1 were overexpressed in IBC as compared to non-IBC tissues. Moreover, there was a significant positive correlation between the expression of CTSB and the number of positive metastatic lymph nodes in IBC.</p> <p>Conclusions</p> <p>CTSB may initiate proteolytic pathways crucial for IBC invasion. Thus, our data demonstrate that CTSB may be a potential prognostic marker for lymph node metastasis in IBC.</p

    Comparative study between fisher anatomical subunit approximation technique and millard rotation- advancement technique in unilateral cleft lip repair

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    Introduction: The ideal lip repair is characterized by; the symmetrical shape of nasolabial folds and both alae of the nose with a natural-looking philtrum and Cupid’s bow in both static and dynamic states, in addition to a hidden scar.Objective: to compare between Fisher anatomical subunit approximation technique and Millard rotational advancement technique in unilateral cleft lip repair.Methods: Prospective study for 40 patients presented to Alexandria Main University hospital with unilateral cleft lip deformity between March 2019 and October 2020. Twenty patients with unilateral cleft lip deformity were repaired by Fisher anatomical subunit approximation technique, while the other twenty were repaired by Millard rotational-advancement technique. The postoperative photographs of the patients were captured and processed in computer photogrammetry software through which anthropometric parameters including (lip height, lip width, vermilion height, and alar base width) were compared between the normal side and the repaired side. In this software, each anthropometric parameter length on the normal side is taken as a control with a fixed value of (1) then the same parameter on the repaired side was measured as a ratio of this value to avoid bias. Comparison between both groups for assessment of the quality of cleft lip repair was also done based on Steffensen grading criteria.Results: Comparison between both techniques in unilateral cleft lip repair showed that there was no significant difference between them in the anthropometric measurements. While the comparison between the two groups using Steffensen grading criteria showed that Fisher’s technique surpassed Millard’s technique.Conclusion: We recommend the use of the Fisher anatomical subunit approximation technique in unilateral cleft lip repair for its superior results over the Millard rotational advancement technique

    Direct Enantiomeric Resolution of Betaxolol with Application to Analysis of Pharmaceutical Products

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    A high-performance liquid chromatographic (HPLC) method has been developed for the separation and determination of S- and R-enantiomers of betaxolol in tablets and ophthalmic preparations. Baseline resolution was achieved by using teicoplanin macrocyclic antibiotic chiral stationary phase (CSP) known as Chirobiotic T with fluorescence detection at excitation/emission wavelengths 275/305 nm. The polar ionic mobile phase (PIM) consists of methanol-glacial acetic acid-triethylamine, (100:0.020:0.025, v/v/v) has been used at a flow rate of 1.5 ml/min. All analytes with S-(–)-atenolol as internal standard were conducted at ambient temperature. The method is highly specific where another coformulated compounds did not interfere. The stability of betaxolol enantiomers under different degree of temperature also studied. The results showed that it is stable for at least 7 days at 70°C. The method validated for its linearity, accuracy, precision and robustness. Experimental design was used during validation to evaluate method robustness. Using the chromatographic conditions described, S- and R-betaxolol were well resolved with mean retention times of 11.3 and 12.6 min, respectively. Linear response (r > 0.997) was observed over the range of 10–500 ng/ml of betaxolol enantiomers, with detection limit of 5 ng/ml. The recoveries of S- and R-betaxolol from tablets and ophthalmic preparation ranged from 97.4 to 101.4% and 98.0 to 102.0%, respectively. The mean relative standard deviation (R.S.D.%) for both enantiomers were 1.1–1.4% and 1.3–1.7% in tablets and ophthalmic solution, respectively

    Streptomyces noboritoensis isolated from rhizosphere soil and its use in controlling banana-tissue culture contaminants

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    In this study, the role of Streptomyces noboritoensis (14) isolated from the rhizosphere of banana plant and having antagonistic activity against the bacterial- and fungal-tissue culture contaminants was determined in vitro. Results show that the filtrate was more effective against the fungal-tissue culture contaminants than the bacterial-tissue culture contaminants. This was indicated when jars were fungifree and bacteria-free after one month and 21 days from incubation, respectively. Results of in vitro application show that the filtrate of S. noboritoensis (14) as a bio-control agent could be used for controlling the contaminants in banana. Data showed that treatment F (sterilized shoots treated with Streptomyces filtrate and cultivated on Streptomyces-inoculated medium) was the most effective followed by treatment E (sterilized shoots untreated with Streptomyces filtrate and cultivated on Streptomyces-inoculated medium). Therefore, the study suggests conducting further studies towards the use of streptomycetes in the biological control in a large scale production.Keywords: Streptomyces, tissue culture contaminants, antagonistic activities, bio-controlAfrican Journal of Biotechnology Vol. 12(20), pp. 2908-291

    Mediating Service Recovery Satisfaction in the Relationship between Internet Service Recovery and Customer Loyalty

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    This current study purposes to identify the relationships between service recovery strategies, service recovery satisfaction, and both dimensions of customer loyalty in regard to Internet providers using the partial least squares (PLS-SEM) approach on a sample of 430 internet customers in Egypt. This study contributes insights into how seven service recovery strategies affected customer loyalty with its both attitudinal and behavioral dimensions directly and indirectly via service recovery satisfaction. These insights are helpful for service managers faced with service failure and academicians interested in how service providers respond to service failures and customer dissatisfaction in the B2C context. The results of this study show that some SR strategies positively influence both service recovery satisfaction and customer loyalty toward internet providers. Furthermore, service recovery satisfaction positively influencing the customer loyalty. In addition, SRS plays a mediating role in the relationship between SR strategies and customer loyalty. The results highlight that internet service providers should implement SR strategies quickly and with an empathetic manner to satisfy customers and to encourage customer's loyalty. Finally, some implications and further research directions were presented

    Multi-parametric arterial spin labelling and diffusion-weighted magnetic resonance imaging in differentiation of grade II and grade III gliomas

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    Purpose: To assess arterial spin labelling (ASL) perfusion and diffusion MR imaging (DWI) in the differentiation of grade II from grade III gliomas. Material and methods: A prospective cohort study was done on 36 patients (20 male and 16 female) with diffuse gliomas, who underwent ASL and DWI. Diffuse gliomas were classified into grade II and grade III. Calculation of tumoural blood flow (TBF) and apparent diffusion coefficient (ADC) of the tumoral and peritumoural regions was made. The ROC curve was drawn to differentiate grade II from grade III gliomas. Results: There was a significant difference in TBF of tumoural and peritumoural regions of grade II and III gliomas (p = 0.02 and p =0.001, respectively). Selection of 26.1 and 14.8 ml/100 g/min as the cut-off for TBF of tumoural and peritumoural regions differentiated between both groups with area under curve (AUC) of 0.69 and 0.957, and accuracy of 77.8% and 88.9%, respectively. There was small but significant difference in the ADC of tumoural and peritumoural regions between grade II and III gliomas (p = 0.02 for both). The selection of 1.06 and 1.36 × 10-3 mm2/s as the cut-off of ADC of tumoural and peritumoural regions was made, to differentiate grade II from III with AUC of 0.701 and 0.748, and accuracy of 80.6% and 80.6%, respectively. Combined TBF and ADC of tumoural regions revealed an AUC of 0.808 and accuracy of 72.7%. Combined TBF and ADC for peritumoural regions revealed an AUC of 0.96 and accuracy of 94.4%. Conclusion: TBF and ADC of tumoural and peritumoural regions are accurate non-invasive methods of differentiation of grade II from grade III gliomas

    Phytochemical Investigation of Egyptian Spinach Leaves, a Potential Source for Antileukemic Metabolites: In Vitro and In Silico Study

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    Spinacia oleracea L., Amaranthaceae, leaves cultivated in Egypt demonstrated a potential antileukemic activity against the chronic myeloid leukemia, K562 cell line. Thus, the aim of this study is to carry out a phytochemical investigation of S. oleracea leaves as well as the isolation of its antileukemic phytoconstituents. Phytochemical investigation of S. oleracea leaves resulted in the isolation of seventeen known compounds. The biological study revealed that compounds hexaprenol, phytol, and 18-[(1-oxohexadecyl) oxy]-9-octadecenoic acid exhibited a remarkable antiproliferative activity against K562 cells in vitro. A mechanistic in silico study showed that hexaprenol, phytol, and 18-[(1-oxohexadecyl) oxy]-9-octadecenoic acid exhibited a strong binding affinity towards topoisomerase (docking score −12.50, −9.19, and −13.29 kcal/mol, respectively), and showed as well a strong binding affinity towards Abl kinase (docking score −11.91, −9.35, and −12.59 kcal/mol, respectively). Molecular dynamics study revealed that 18-[(1-oxohexadecyl) oxy]-9-octadecenoic acid produced stable complexes with both topoisomerase and Abl kinase with RMSD values of 1.81 and 1.85 Å, respectively. As a result of our findings, we recommend more in vivo and preclinical studies to confirm the potential benefit of spinach leaves for chronic myeloid leukemia patients. Graphical Abstract: [Figure not available: see fulltext.

    Taxonomy of Streptomyces strains isolated from rhizospheres of various plant species grown in Taif region, KSA, having antagonistic activities against some microbial tissue culture contaminants

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    This work was designed to identify and taxonomically classify Streptomyces strains isolated from the rhizospheres of various plant species; banana, rose, pomegranate and grape plants, having antagonistic activity against some microbial (bacteria and fungi) tissue culture contaminants. Streptomyces strains with the most potent antagonistic traits were identified using sequencing of 16S rRNA gene amplicons generated by PCR of DNA and blasting the sequences into GenBank. The Streptomyces isolates had antagonism against five identified fungi (Aspergillus fumigates, Aspergillus flavus, Aspergillus nidulans (1), Aspergillus nidulans (2), Cladosporium herbarum) and against five out of the 11 Gram positive bacilli bacterial contaminants. The three selected Streptomyces isolates (14, 15 and 17) were identified as strains of Streptomyces noboritoensis, Streptomyces albolongus and Streptomyces griseorubiginosus, respectively. Isolate 14 for which 1443 nucleotides were obtained was compared with eight universal Streptomyces strains and was classified as a new species of gray Streptomyces, to be named Streptomyces noboritoensis SSMA2-KSA strain. This study recommends conducting further studies on the use of streptomycetes in the biological control in a large scale production.Keywords: Taxonomy, Streptomyces, microbial tissue culture contaminants, antagonistic activities, 16S rRNAAfrican Journal of Biotechnology Vol. 12(14), pp. 1657-166

    The Relationship between Service Recovery and Patronage Intentions: The Mediating Role of Relationship Quality

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    This study aims to investigate, using the structural equation modeling with a partial least square (PLS-SEM) approach, the relationship among service recovery strategies, relationship quality, and customer patronage intentions concerning Internet Service Providers (ISPs) in Egypt. Our findings confirmed that some service recovery strategies positively influence on both relationship quality and patronage intentions. As well as, relationship quality has a significant impact on customer patronage intentions. Furthermore, relationship quality has the role of a mediator of the relationship between SR strategies and patronage intention. Moreover, both speeds of recovery and empathy moderate the relationship between some SR strategies and relationship quality. Finally, our study proposed some theoretical and managerial implications
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