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1.
Int J Cardiol ; 408: 132116, 2024 Aug 01.
Article En | MEDLINE | ID: mdl-38703898

The management of heart failure has undergone significant evolution, advancing from the initial utilization of digitalis and diuretics to the contemporary practice of personalized medicine and sophisticated device therapy. Despite these advancements, the persistent challenge of high hospitalization and readmission rates underscores an urgent need for innovative solutions. This manuscript explores how the integration of digital health technologies into interventional cardiology marks a paradigm shift in the management of heart failure. These technologies are no longer mere adjuncts but have become foundational to a modern approach, providing tools for continuous monitoring, patient education, and improved outcomes post-intervention. Through an examination of current trends, this perspective article highlights the transformative impact of wearable technologies, telehealth platforms, and advanced analytical tools in reshaping patient engagement and enabling proactive care strategies. Case studies illustrate the practical advantages, including enhanced medication adherence, early detection of heart failure signs, and a reduction in healthcare facility burdens. Central to this new digital health landscape is the Information Technology Management (ITM) system, a framework poised to revolutionize patient and caregiver engagement and pave the way for the future of interventional cardiology. This manuscript delineates the ITM system's innovative architecture and its consequential role in refining current and prospective cardiological interventions.


Caregivers , Heart Failure , Patient Participation , Telemedicine , Humans , Heart Failure/therapy , Patient Participation/methods , Disease Management , Biomedical Technology/trends , Biomedical Technology/methods , Digital Technology , Digital Health
2.
Sensors (Basel) ; 24(5)2024 Feb 23.
Article En | MEDLINE | ID: mdl-38474985

Computer vision in the structural health monitoring (SHM) field has become popular, especially for processing unmanned aerial vehicle (UAV) data, but still has limitations both in experimental testing and in practical applications. Prior works have focused on UAV challenges and opportunities for the vibration-based SHM of buildings or bridges, but practical and methodological gaps exist specifically for linear infrastructure systems such as pipelines. Since they are critical for the transportation of products and the transmission of energy, a feasibility study of UAV-based SHM for linear infrastructures is essential to ensuring their service continuity through an advanced SHM system. Thus, this study proposes a single UAV for the seismic monitoring and safety assessment of linear infrastructures along with their computer vision-aided procedures. The proposed procedures were implemented in a full-scale shake-table test of a natural gas pipeline assembly. The objectives were to explore the UAV potential for the seismic vibration monitoring of linear infrastructures with the aid of several computer vision algorithms and to investigate the impact of parameter selection for each algorithm on the matching accuracy. The procedure starts by adopting the Maximally Stable Extremal Region (MSER) method to extract covariant regions that remain similar through a certain threshold of image series. The feature of interest is then detected, extracted, and matched using the Speeded-Up Robust Features (SURF) and K-nearest Neighbor (KNN) algorithms. The Maximum Sample Consensus (MSAC) algorithm is applied for model fitting by maximizing the likelihood of the solution. The output of each algorithm is examined for correctness in matching pairs and accuracy, which is a highlight of this procedure, as no studies have ever investigated these properties. The raw data are corrected and scaled to generate displacement data. Finally, a structural safety assessment was performed using several system identification models. These procedures were first validated using an aluminum bar placed on an actuator and tested in three harmonic tests, and then an implementation case study on the pipeline shake-table tests was analyzed. The validation tests show good agreement between the UAV data and reference data. The shake-table test results also generate reasonable seismic performance and assess the pipeline seismic safety, demonstrating the feasibility of the proposed procedure and the prospect of UAV-based SHM for linear infrastructure monitoring.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124159, 2024 May 15.
Article En | MEDLINE | ID: mdl-38508074

The present study is focused on the sensitive determination of newly FDA-approved glucagon-like-peptide agonists semaglutide (SEM) and tirzepatide (TIR). Direct, selective and label-free spectrofluorometric method was proposed and validated (according to ICH guidelines) for determination SEM and TIR in their pure form, newly approved pharmaceuticals and spiked human plasma. The developed method was based on measuring the native fluorescence of SEM and TIR in ethanol at 294.8 and 303 nm after being excited at 216 and 225 nm for SEM and TIR in order. The method sensibility allowed the quantification of both drugs in nano-scale up to 10 ng/mL. Several experimental variables including solvent type, surfactant, and pH were optimized after several attempts to get the best sensitivity for both drugs. The mean recovery percentage of SEM was compared and found in agreement with the reported method using student's t-test and the variance ratio F-test. Additionally, the greenness and whiteness profiles for this approach were evaluated using the GAPI, AGREE, and RGB algorithm; the positive results supported its use as great candidates for successful implementation in quality control labs and the pharmaceutical analysis companies.


Algorithms , Gastric Inhibitory Polypeptide , Glucagon-Like Peptide-2 Receptor , Glucagon-Like Peptides , Humans , Coloring Agents
4.
Microbes Infect ; 26(1-2): 105241, 2024.
Article En | MEDLINE | ID: mdl-38380602

Transplacental transmission of syphilis causing spirochete, Treponema pallidum subspecies pallidum, from mother to child results in congenital syphilis, an ever-expanding devastating disease worldwide. Although adverse effects of untreated gestational Lyme disease, caused by a related spirochete, Borrelia burgdorferi on fetus viability and development have been observed, cases of congenital Lyme disease are not reported. In this study, we show that B. burgdorferi colonizes mammary glands of C3H mice only postpartum; however, neither transmission of these spirochetes from dams-to-pups occurs nor congenital Lyme disease is observed in pups.


Borrelia burgdorferi , Lyme Disease , Mammary Glands, Human , Treponema , Humans , Mice , Animals , Child , Female , Mice, Inbred C3H , Lactation , Infectious Disease Transmission, Vertical
5.
Sci Rep ; 13(1): 21121, 2023 11 30.
Article En | MEDLINE | ID: mdl-38036558

A robust, stability-indicating, and eco-friendly proton nuclear magnetic resonance (1H-qNMR) method was developed for the concurrent determination of three 1,4-benzodiazepines (BDZs), namely diazepam (DZP), alprazolam (ALP), and chlordiazepoxide (CDP) and their common impurity, synthesis precursor, and degradation product; 2-amino-5-chlorobenzophenone (ACB). In the present method, a novel approach was developed for composing a green and cost-efficient solvent system as an alternative to the common NMR organic solvents utilizing 0.3 M sodium dodecyl sulfate prepared in deuterated water. The conducted method is characterized by simplicity with no need for sample pretreatment or labeling. Phloroglucinol was used as an internal standard. The chosen signals for the determinations of ALP, CDP, DZP and ACB were at 2.35 ppm (singlet), 2.84 ppm (singlet), 3.11 ppm (singlet), and 6.90 ppm (doublet of doublet), respectively. The proposed method possessed linearity over the concentration range of 0.25-15.0 mg ml-1 for DZP, ALP, CDP and of 0.5-25.0 mg ml-1 for ACB with LOD values of 0.06, 0.03, 0.07 and 0.16 mg ml-1 respectively, and LOQ values of 0.18, 0.09, 0.21 and 0.49 mg ml-1, respectively. Accuracy of the method was evidenced by excellent recovery% (99.57-99.90%) and small standard deviation (≥ 1.10) for the three analyzed drugs. Intra- and inter-day precision were determined with coefficient of variation ranging from 0.12 to 1.14 and from 0.72 to 1.67, respectively. For the studied compounds, appraisal of the method greenness was achieved via four approaches: Analytical Eco-Scale, Green Analytical Procedure Index (GAPI), Analytical greenness metric (AGREE), and RGB Additive Color Model. The results proved that the proposed method has the privilege of being a green analytical method.


Benzodiazepines , Benzophenones , Diazepam , Magnetic Resonance Spectroscopy , Solvents
6.
Bioorg Chem ; 141: 106874, 2023 12.
Article En | MEDLINE | ID: mdl-37769524

New series of substituted 2-alkoxycyanopyridine derivatives were synthesized and evaluated for their in vitro and in vivo anticancer activities. Comparing the evaluated activities against cancer cell lines to the broad-spectrum anticancer doxorubicin, and the kinase inhibitor sorafenib, compounds 3a, 4b, 4c, 7a, and 8d demonstrated superior anticancer efficacy with elevated safety profiles and selectivity indices, particularly against MCF7 breast cancer. For exploration of their mechanism of action, assays for inhibition of EGFR, HER2 kinase, and DHFR were performed. The promising synthesized compounds exhibited potent dual kinase EGFR/HER2 inhibitory activity with IC50values of 0.248/0.156 µM for 4b and 0.138/0.092 µM for 4c. Additionally, with IC50 values of 0.138 and 0.193 M, respectively, 4b and 4c had the greatest DHFR inhibitory activity that was comparable to methotrexate. In the MCF7 breast cancer cell line, they caused arrest at the S phase of the cell cycle and exhibited apoptosis induction activity. With restored caspase-3 immunoexpression, the anti-breast cancer assay performed in vivo of 4b and 4c demonstrated a substantial decrease in tumor volume. Results from molecular modeling were in agreement with biological assays proving the importance of the 3-caynopyridine, two substituted phenyl rings attached to central pyridine ring, and propoxy side chain moieties for binding with the receptors. As 4c works by inhibiting both EGFR/HER2 kinase, DHFR enzymes, in addition to cellular apoptosis, it could be viewed as a model of compounds possessing a multi-targeting anticancer activity. Collectively, compounds 4b and 4c might represent prototypes for further development as anticancer molecules.


Antineoplastic Agents , Breast Neoplasms , Humans , Female , Molecular Structure , Structure-Activity Relationship , ErbB Receptors , Drug Screening Assays, Antitumor , Antineoplastic Agents/chemistry , Apoptosis , Protein Kinase Inhibitors , Breast Neoplasms/drug therapy , Cell Proliferation , Cell Line, Tumor , Molecular Docking Simulation
7.
Anal Chim Acta ; 1237: 340592, 2023 Jan 02.
Article En | MEDLINE | ID: mdl-36442950

In this study, we report a one-pot, green, cost-efficient, and fast synthesis of plant-based sulfur and nitrogen self-co-doped carbon quantum dots (S,N-CQDs). By 4-min microwave treatment of onion and cabbage juices as renewable, cheap, and green carbon sources and self-passivation agents, blue emissive S,N-CQDs have been synthesized (λex/λem of 340/418 nm) with a fluorescence quantum yield of 15.2%. A full characterization of the natural biomass-derived quantum dots proved the self-doping with nitrogen and sulfur. The S,N-CQDs showed high efficiency as a fluorescence probe for sensitive determination of nitazoxanide (NTZ), that recently found wide applicability as a repurposed drug for COVID-19, over the concentration range of 0.25-50.0 µM with LOD of 0.07 µM. The nanoprobe has been successfully applied for NTZ determination in pharmaceutical samples with excellent % recovery of 98.14 ± 0.42. Furthermore, the S,N-CQDs proved excellent performance as a sensitive fluorescence nanoprobe for determination of hemoglobin (Hb) over the concentration range of 36.3-907.5 nM with a minimum detectability of 10.30 nM. The probe has been applied for the determination of Hb in blood samples showing excellent agreement with the results documented by a medical laboratory. The greenness of the developed probe has been positively investigated by different greenness metrics and software. The green character of the proposed analytical methods originates from the synthesis of S,N-CQDs from sustainable, widely available, and cheap plants via low energy/low cost microwave-assisted technique. Omission of organic solvents and harsh chemicals beside dependence on mix-and-read analytical approach corroborate the method greenness. The obtained results demonstrated the substantial potential of the synthesized green, safe, cheap, and sustainable S,N-CQDs for pharmaceutical and biological applications.


COVID-19 , Quantum Dots , Humans , Antiviral Agents , Carbon , Fluorescent Dyes , Hemoglobins , Microwaves , Nitrogen , Sulfur
8.
Polymers (Basel) ; 14(9)2022 May 04.
Article En | MEDLINE | ID: mdl-35567047

Understanding material behavior is key to discovering innovative applications in any field. Regardless of the exciting mechanical properties of polyurea, there has been a limited effort in studying the use of polyurea for structural retrofit and strengthening applications. This study aims to understand the behavior of polyurea under different tensile loading conditions to provide critical information towards enabling the future use of polyurea in structural applications. Several standard coupons are tested under various tensile loading conditions to understand the mechanical behavior of eight different commercial polyureas. The study provides the full stress-strain characteristic curves that can be used for constitutive modeling purposes. The results show that polyurea has a wide range of properties from low strength flexible nature to high strength rigid nature. All tested polyureas displayed some level of rate dependency, i.e., ultimate strength is a function of loading rates. The high-strength polyureas tested only show slight rate dependency and good strength retention under cyclic and fatigue tensile loading, suggesting that polyureas have promising mechanical properties for potential structural applications.

9.
Materials (Basel) ; 14(22)2021 Nov 18.
Article En | MEDLINE | ID: mdl-34832366

Full-depth precast bridge decks are widely used to expedite bridge construction and enhance durability. These deck systems face the challenge that their durability and performance are usually dictated by the effectiveness of their field joints and closure joint materials. Hence, commercial ultra-high performance concrete (UHPC) products have gained popularity for use in such joints because of their superior mechanical properties. However, the proprietary and relatively expensive nature of the robust UHPC mixes may pose some limitations on their future implementation. For these reasons, many research agencies along with state departments of transportation sought their way to develop cheaper non-proprietary UHPC (NP-UHPC) mixes using locally supplied materials. The objective of this study is to demonstrate the full-scale application of the recently developed NP-UHPC mixes at the ABC-UTC (accelerated bridge construction university transportation center) in transverse field joints of precast bridge decks. This study included experimental testing of three full-scale precast bridge deck subassemblies with transverse NP-UHPC field joints under static vertical loading. The test parameters included NP-UHPC mixes with different steel fibers amount, different joint splice details, and joint widths. The results of this study were compared with the results of a similar proprietary UHPC reference specimen. The structural behavior of the test specimens was evaluated in terms of the load versus deflection, reinforcement and concrete strains, and full assessment of the field joint performance. The study showed that the proposed NP-UHPC mixes and field joint details can be efficiently used in the transverse deck field joints with comparable behavior to the proprietary UHPC joints. The study concluded that the proposed systems remained elastic under the target design service and ultimate loads. In addition, the study showed that the use of reinforcement loop splices enhanced the load distribution across the specimen's cross-section.

10.
Sci Rep ; 11(1): 17202, 2021 08 25.
Article En | MEDLINE | ID: mdl-34433838

Autochthonous Sudanese cattle breeds, namely Baggara for beef and Butana and Kenana for dairy, are characterized by their adaptive characteristics and high performance in hot and dry agro-ecosystems. They are thus used largely by nomadic and semi-nomadic pastoralists. We analyzed the diversity and genetic structure of the BoLA-DRB3 gene, a genetic locus linked to the immune response, for the indigenous cattle of Sudan and in the context of the global cattle repository. Blood samples (n = 225) were taken from three indigenous breeds (Baggara; n = 113, Butana; n = 60 and Kenana; n = 52) distributed across six regions of Sudan. Nucleotide sequences were genotyped using the sequence-based typing method. We describe 53 alleles, including seven novel alleles. Principal component analysis (PCA) of the protein pockets implicated in the antigen-binding function of the MHC complex revealed that pockets 4 and 9 (respectively) differentiate Kenana-Baggara and Kenana-Butana breeds from other breeds. Venn analysis of Sudanese, Southeast Asian, European and American cattle breeds with 115 alleles showed 14 were unique to Sudanese breeds. Gene frequency distributions of Baggara cattle showed an even distribution suggesting balancing selection, while the selection index (ω) revealed the presence of diversifying selection in several amino acid sites along the BoLA-DRB3 exon 2 of these native breeds. The results of several PCA were in agreement with clustering patterns observed on the neighbor joining (NJ) trees. These results provide insight into their high survival rate for different tropical diseases and their reproductive capacity in Sudan's harsh environment.


Cattle/genetics , Haplotypes , Histocompatibility Antigens Class II/genetics , Phylogeny , Polymorphism, Single Nucleotide , Animals , Cattle/classification , Evolution, Molecular , Sudan
11.
Sensors (Basel) ; 20(23)2020 Nov 30.
Article En | MEDLINE | ID: mdl-33266029

Much research is still underway to achieve long-term and real-time monitoring using data from vision-based sensors. A major challenge is handling and processing enormous amount of data and images for either image storage, data transfer, or image analysis. To help address this challenge, this study explores and proposes image compression techniques using non-adaptive linear interpolation and wavelet transform algorithms. The effect and implication of image compression are investigated in the close-range photogrammetry as well as in realistic structural health monitoring applications. For this purpose, images and results from three different laboratory experiments and three different structures are utilized. The first experiment uses optical targets attached to a sliding bar that is displaced by a standard one-inch steel block. The effect of image compression in the photogrammetry is discussed and the monitoring accuracy is assessed by comparing the one-inch value with the measurement from the optical targets. The second application is a continuous static test of a small-scale rigid structure, and the last application is from a seismic shake table test of a full-scale 3-story building tested at E-Defense in Japan. These tests aimed at assessing the static and dynamic response measurement accuracy of vision-based sensors when images are highly compressed. The results show successful and promising application of image compression for photogrammetry and structural health monitoring. The study also identifies best methods and algorithms where effective compression ratios up to 20 times, with respect to original data size, can be applied and still maintain displacement measurement accuracy.

12.
Materials (Basel) ; 13(18)2020 Sep 14.
Article En | MEDLINE | ID: mdl-32937848

Bridge structures nationwide across the United States are aging and in need of repair or, in some cases, full replacement. Repair decisions are common among bridge owners because of the economic feasibility when compared to the higher cost of full replacement of damaged or deteriorated bridge components such as girders. Using a proper repair approach, as a long-term or just a short-term solution, can lead to benefits that could not be achieved otherwise such as considerable savings in both time and cost. Additionally, an appropriate repair approach can help avoid adverse environmental impacts, interruptions to service, overburdening of nearby infrastructure, and local opposition to construction. The main objective of this paper is to provide a synthesis of the repair methods and materials for reinforced concrete bridge girders proposed in research studies, i.e., state-of-the-art as well as state-of-the-practice established methods. Different steps in the general repair procedure are explained first. Next, a detailed description of three common bridge girder deficiencies, i.e., shear, flexural, and fire damage, is provided. For each damage type, the main causes and common solutions found in the literature are presented. The authors then provide specific recommendations to each repair procedure. This is intended to enable researchers, engineers, and decision makers to compare the available repair methods more conveniently to find the optimal repair approach for specific projects based on economic and environmental requirements as well as structural and construction conditions.

13.
IEEE Trans Neural Netw Learn Syst ; 31(7): 2522-2531, 2020 Jul.
Article En | MEDLINE | ID: mdl-31484135

The power of quantum computers is still somewhat speculative. Although they are certainly faster than classical ones at some tasks, the class of problems they can efficiently solve has not been mapped definitively onto known classical complexity theory. This means that we do not know for which calculations there will be a "quantum advantage," once an algorithm is found. One way to answer the question is to find those algorithms, but finding truly quantum algorithms turns out to be very difficult. In previous work, over the past three decades, we have pursued the idea of using techniques of machine learning to develop algorithms for quantum computing. Here, we compare the performance of standard real- and complex-valued classical neural networks with that of one of our models for a quantum neural network, on both classical problems and on an archetypal quantum problem: the computation of an entanglement witness. The quantum network is shown to need far fewer epochs and a much smaller network to achieve comparable or better results.

14.
Z Naturforsch C J Biosci ; 71(1-2): 29-35, 2016.
Article En | MEDLINE | ID: mdl-26845717

Three triterpenoidal derivatives [Sipholenol A (1), sipholenol L (2) and sipholenone A (3)] were isolated from the Red Sea sponge Siphonochalina sp. The structures were determined based on spectroscopic measurements (NMR, UV, IR and MS). The isolated compounds were evaluated for their cytotoxic activity against three cancer cell lines; HepG2, Caco-2 and HT-29. Moreover, the effects of these metabolites on cell cycle progression as well as cell cycle regulating proteins were assessed. Compounds 1, 2 and 3 showed moderate activity against HepG2 cells with IC(50) values of 17.18 ± 1.18, 24.01 ± 0.59 and 35.06 ± 1.10 µM, respectively. Compounds 1 and 2 exerted a considerable antiproliferative effect with IC(50) values of 4.80 ± 0.18 and 26.64 ± 0.30 µM, respectively, against Caco-2 cells. Finally, 1 and 2 exhibited antiproliferative activity against colorectal cancer cells (HT-29) with IC(50) values of 24.65 ± 0.80 and 4.48 ± 0.1 µM, respectively. Cell cycle analysis indicated that these compounds induced cell cycle arrest particularly in G0/G1 and S phases. Furthermore, the triterpenoids increased the expression of cyclin-B1, cyclin-D1 and cleaved caspase-3, as determined by immunofluorescence, indicating an important role of apoptosis in cell death induced by these compounds.


Cell Cycle/drug effects , Colorectal Neoplasms/drug therapy , Liver Neoplasms/drug therapy , Terpenes/administration & dosage , Animals , Caco-2 Cells , Cell Proliferation/drug effects , Colorectal Neoplasms/pathology , Hep G2 Cells , Humans , Liver Neoplasms/pathology , Porifera/chemistry
15.
Joint Bone Spine ; 80(6): 626-31, 2013 Dec.
Article En | MEDLINE | ID: mdl-23731641

OBJECTIVE: To investigate whether miRNA-499 (rs3746444) and miRNA-146a (rs2910164) genes polymorphisms are independent factors for rheumatoid arthritis (RA) in Egyptians, and whether they influence disease severity and activity. METHODS: Two hundred and seventeen RA patients and 245 healthy controls were enrolled in this study. Polymorphisms of miRNA-146a and miRNA-499 genes were detected using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). RESULTS: The miRNA-499 CT genotype was an independent factor of RA. The miRNA-499 CT, CC genotypes and C allele frequencies were significantly increased in erosive RA group. Moreover, the heterozygote CT had more severe and more active form of the disease compared with homozygote CC or TT. However, we did not find any significant association of miRNA-146a polymorphism with RA risk, severity, and activity. CONCLUSION: The miRNA-499 polymorphism is an independent factor of RA, and influences disease severity and activity.


Arthritis, Rheumatoid/genetics , MicroRNAs/genetics , Adult , Egypt , Female , Gene Frequency , Genetic Predisposition to Disease , Genotype , Humans , Middle Aged , Polymorphism, Genetic , Risk Factors
16.
Arch Pharm (Weinheim) ; 337(8): 427-33, 2004 Aug.
Article En | MEDLINE | ID: mdl-15293261

New sydnone derivatives bearing a substituted phenyl ring at the 3-position have been synthesized. Two separate series of 3-(carboxyphenyl)sydnone derivatives have been prepared by cyclization of the corresponding N-nitroso-N-(carboxyphenyl)-glycine 3. The obtained 3-(carboxyphenyl)sydnones 4 were subjected to a series of different chemical reactions on the carboxylic acid group. Compound 5, the potassium salt of 4a, was reacted with alpha-chloroacetanilide derivatives 6 to give the corresponding esters 7. On the other hand, the acid hydrazide 9 was condensed with different aromatic aldehydes to give the corresponding arylidene derivatives 10. The synthesized compounds were tested for their antibacterial activities against both gram-positive and gram-negative organisms. Some of the test compounds exhibited high activity; among them, 10d is considered to be a lead compound possessing high broad-spectrum antibacterial activity.


Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/pharmacology , Sydnones/chemical synthesis , Sydnones/pharmacology , Bacteria/drug effects , Chemical Phenomena , Chemistry, Physical , Indicators and Reagents , Microbial Sensitivity Tests
17.
Arch Pharm (Weinheim) ; 337(3): 164-70, 2004 Mar.
Article En | MEDLINE | ID: mdl-15038062

Several series of 3-phenylsydnone derivatives conjugated to well-known moieties with antibacterial activity were synthesized via several routes. These derivatives include 3-cyano-2-oxopyridine, 2-amino-3-cyanopyridine, 2-arylidene-1-ethylidenehydrazine and 2-aroyl-1-ethylidenehydrazine moieties. Thus, the key intermediate 3-(4-acetylphenyl)sydnone (3) was allowed to react with the appropriate aldehyde, ethyl cyanoacetate or malononitrile in presence of excess ammonium acetate in two steps (method 1) or through a one-pot reaction technique (methods 2 and 3) to give the corresponding sydnone derivatives 5 and 6, respectively. Moreover, condensation of compound 3 with hydrazine hydrate followed by the reaction with the appropriate aldehyde, mono- and dicarboxylic acid hydrazide yielded the corresponding sydnone derivatives 8, 9 and 10, respectively. Most of the synthesized compounds were screened for their in vitro antibacterial activity against various pathogenic organisms of both Gram-positive and Gram-negative bacteria. The minimum inhibitory concentrations (MICs) were determined using agar dilution method.


Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/pharmacology , Drug Evaluation, Preclinical/methods , Structure-Activity Relationship , Sydnones/chemical synthesis , Sydnones/pharmacology , Ciprofloxacin/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , In Vitro Techniques , Microbial Sensitivity Tests
18.
J Pharm Biomed Anal ; 34(1): 35-44, 2004 Jan 27.
Article En | MEDLINE | ID: mdl-14738917

Two sensitive, simple and specific methods based on spectrophotometry and reversed-phase HPLC with fluorimetric detection are described for the determination of lisinopril in dosage forms as well as in spiked human plasma using solid phase extraction (SPE) procedures. Both methods are based on the derivatization of lisinopril with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) in borate buffer of pH 9 to yield a yellow, fluorescent product. The spectrophotometric method depends on measuring the formed yellow color at 470 nm after optimization of the reaction conditions. The HPLC method is based on measurement of the derivatized product using fluorescence detection at 540 nm (excitation at 470 nm). The separation of the derivatized drug, the excess reagent and the internal standard (bumetanide) was performed on a reversed-phase ODS column using isocratic elution with methanol-0.02 M sodium dihydrogen phosphate, pH 3.0 (55:45, v/v) at a flow rate of 1.0 ml/min. The calibration graphs were linear over the concentration ranges 2-20 or 0.02-3.2 microg/ml of lisinopril with minimum detectability of 0.3 and 0.008 microg/ml (6.1 x 10(-7) and 1.7 x 10(-8)M) for the spectrophotometric and the HPLC methods, respectively. The proposed methods were applied without any interference from the tablet excipients for the determination of lisinopril in dosage forms, either alone or co-formulated with hydrochlorothiazide. Furthermore, the use of the HPLC method was extended to the in vitro determination of the drug in spiked human plasma. Interference from endogenous amino acids has been overcomed by using the solid phase extraction technique, the percentage recovery (n=6) was 101.6+/-3.35.


4-Chloro-7-nitrobenzofurazan/blood , Lisinopril/blood , 4-Chloro-7-nitrobenzofurazan/chemistry , Chromatography, High Pressure Liquid/methods , Dosage Forms , Humans , Lisinopril/chemistry , Spectrophotometry, Ultraviolet/methods
19.
Farmaco ; 58(11): 1179-86, 2003 Nov.
Article En | MEDLINE | ID: mdl-14572869

A simple spectrophotometric method has been developed for the determination of propranolol hydrochloride in pure as well as in dosage forms. The method is based on the oxidative coupling reaction with 3-methylbenzothiazoline-2-one hydrazone. A mixture of an acidic solution of the chromogenic agent and the drug upon treatment with ceric ammonium sulfate produces an orange color peaking at 496 nm. The absorbance-calibration plot was linear over the range 1-10 microg/ml with minimum detectability (S/N=2) of 0.1 microg/ml (3.38x10(-7) M). The molar absorbitivity was 3.195x10(3) l/M/cm with correlation coefficient (n=10) of 0.9999. The different experimental parameters affecting the development and stability of the color were carefully studied and optimized. The proposed method was applied successfully to the determination of propranolol in its dosage forms. A proposal of the reaction pathway was presented.


Hydrazones/analysis , Hydrazones/metabolism , Propranolol/analysis , Propranolol/metabolism , Thiazoles/analysis , Thiazoles/metabolism , Chemistry, Pharmaceutical , Hydrazones/chemistry , Oxidation-Reduction , Propranolol/chemistry , Spectrophotometry, Ultraviolet/methods , Thiazoles/chemistry
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