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Obstetrics and Gynecology Jun 2017Intra-amniotic dye instillation is a useful tool for evaluation of equivocal cases of preterm prelabor rupture of membranes and for genetic amniocentesis in multifetal...
Intra-amniotic dye instillation is a useful tool for evaluation of equivocal cases of preterm prelabor rupture of membranes and for genetic amniocentesis in multifetal gestation. Indigo carmine, the most used and studied dye, is no longer available. We sought to provide a resource of potential dyes for clinical use that summarizes dosing along with maternal, fetal, and neonatal outcomes. We reviewed the literature evaluating the use of alternative agents. Sodium fluorescein has proven clinical usefulness but has side effects when used intravenously. Phenol-sulfonphthalein has reported clinical utility with no cases of maternal, fetal, or neonatal side effects; however, it is not currently available in the United States. Indocyanine green has been used in pregnancy for other indications. Oral phenazopyridine hydrochloride may lead to a false-positive diagnosis of preterm prelabor rupture of membranes. Evans blue and methylene blue have adverse fetal and neonatal effects. Of the dye options available, fluorescein is a readily available commercial option that has the best evidence supporting use and safety for these indications.
Topics: Amniotic Fluid; Coloring Agents; Female; Fetal Membranes, Premature Rupture; Humans; Injections; Pregnancy; Prenatal Diagnosis; Sensitivity and Specificity
PubMed: 28486367
DOI: 10.1097/AOG.0000000000002056 -
Clinical Case Reports Mar 2023Hemorrhagic cystitis is a common complication following the use of cyclophosphamide. Associated dysuria can be painful and there are few good options to relieve pain....
Hemorrhagic cystitis is a common complication following the use of cyclophosphamide. Associated dysuria can be painful and there are few good options to relieve pain. Phenazopyridine has historically been utilized for dysuria and is available over the counter. However, it is associated with hematologic side effects with prolonged use. Here we present a case of a patient who developed Heinz body hemolysis following prolonged administration of phenazopyridine to treat cyclophosphamide-induced hemorrhagic cystitis following hematopoietic stem cell transplant.
PubMed: 36911643
DOI: 10.1002/ccr3.7012 -
Nature Communications Sep 2021Chiral bridged [2,2,1] bicyclic lactones are privileged structural units in pharmaceutics and bioactive nature products. However, the synthetic methods for these...
Chiral bridged [2,2,1] bicyclic lactones are privileged structural units in pharmaceutics and bioactive nature products. However, the synthetic methods for these compounds are rare. Here we report an efficient method for enantioselective construction of bridged [2,2,1] bicyclic lactones bearing a quaternary stereocenter via Rh-catalyzed asymmetric hydroformylation/intramolecular cyclization/pyridium chlorochromate (PCC) oxidation. By employing a hybrid phosphine-phosphite chiral ligand, a series of cyclopent-3-en-1-ols are transformed into corresponding γ-hydroxyl aldehydes with specific syn-selectivity. Then, hemiacetals form in situ and oxidation with PCC in one-pot affords bridged [2,2,1] bicyclic lactones in high yields and excellent enantiomeric excess. Replacing the hydroxyl group by an ester group, cyclopentanecarbaldehydes with a chiral all-carbon quaternary stereocenter in the γ-position can be generated efficiently.
Topics: Aldehydes; Bridged Bicyclo Compounds, Heterocyclic; Cyclization; Cyclopentanes; Formates; Humans; Lactones; Oxidation-Reduction; Phenazopyridine; Phosphines; Phosphites; Stereoisomerism; Water
PubMed: 34489434
DOI: 10.1038/s41467-021-25569-5 -
Molecular Pharmaceutics Apr 2023The purpose of the present study was to evaluate whether the population balance model (PBM) could be a suitable model for the precipitation of weak base and zwitterionic...
The purpose of the present study was to evaluate whether the population balance model (PBM) could be a suitable model for the precipitation of weak base and zwitterionic drugs in the gastrointestinal pH environment. Five poorly soluble drugs were used as model drugs (dipyridamole, haloperidol, papaverine, phenazopyridine, and tosufloxacin). PBM consists of the equations for primary nucleation, secondary nucleation, and particle growth. Each equation has two empirical parameters. The pH shift (pH-dumping) precipitation test (pH 3.0 to 6.5) was used to determine the model parameters for each drug. It was difficult to determine all six parameters by simultaneously fitting them to the precipitation profiles. Therefore, the number of model parameters was reduced from six to three by neglecting the secondary nucleation process and applying a common exponent number for the particle growth equation. Despite reducing the parameter number, PBM appropriately described the precipitation profiles in the pH shift tests. The constructed PBM model was then used to predict the precipitation profiles in an artificial stomach-intestine transfer (ASIT) test. PBM appropriately predicted the precipitation profiles in the ASIT test. These results suggested that PBM can be a suitable model to represent the precipitation of weak base and zwitterionic drugs in the gastrointestinal pH environment for biopharmaceutics modeling and simulation.
Topics: Solubility; Administration, Oral; Gastrointestinal Tract; Stomach; Computer Simulation; Hydrogen-Ion Concentration; Models, Biological; Chemical Precipitation; Intestinal Absorption
PubMed: 36929729
DOI: 10.1021/acs.molpharmaceut.3c00088 -
Brain : a Journal of Neurology Mar 2017Diverse neurodegenerative disorders are characterized by deposition of tau fibrils composed of conformers (i.e. strains) unique to each illness. The development of tau...
Diverse neurodegenerative disorders are characterized by deposition of tau fibrils composed of conformers (i.e. strains) unique to each illness. The development of tau imaging agents has enabled visualization of tau lesions in tauopathy patients, but the modes of their binding to different tau strains remain elusive. Here we compared binding of tau positron emission tomography ligands, PBB3 and AV-1451, by fluorescence, autoradiography and homogenate binding assays with homologous and heterologous blockades using tauopathy brain samples. Fluorescence microscopy demonstrated intense labelling of non-ghost and ghost tangles with PBB3 and AV-1451, while dystrophic neurites were more clearly detected by PBB3 in brains of Alzheimer's disease and diffuse neurofibrillary tangles with calcification, characterized by accumulation of all six tau isoforms. Correspondingly, partially distinct distributions of autoradiographic labelling of Alzheimer's disease slices with 11C-PBB3 and 18F-AV-1451 were noted. Neuronal and glial tau lesions comprised of 4-repeat isoforms in brains of progressive supranuclear palsy, corticobasal degeneration and familial tauopathy due to N279K tau mutation and 3-repeat isoforms in brains of Pick's disease and familial tauopathy due to G272V tau mutation were sensitively detected by PBB3 fluorescence in contrast to very weak AV-1451 signals. This was in line with moderate 11C-PBB3 versus faint 18F-AV-1451 autoradiographic labelling of these tissues. Radioligand binding to brain homogenates revealed multiple binding components with differential affinities for 11C-PBB3 and 18F-AV-1451, and higher availability of binding sites on progressive supranuclear palsy tau deposits for 11C-PBB3 than 18F-AV-1451. Our data indicate distinct selectivity of PBB3 compared to AV-1451 for diverse tau fibril strains. This highlights the more robust ability of PBB3 to capture wide-range tau pathologies.
Topics: Autoradiography; Benzothiazoles; Brain; Butadienes; Carbolines; Diagnosis; Female; Fluorescence; Humans; Male; Neurofibrillary Tangles; Phenazopyridine; Positron-Emission Tomography; Radioligand Assay; Radiopharmaceuticals; Tauopathies; Thiadiazoles; tau Proteins
PubMed: 28087578
DOI: 10.1093/brain/aww339 -
Journal of Family Medicine and Primary... Jun 2019We present here a case of severe dyspnea after a percutaneous nephrostolithotomy, which resulted from an urinothorax, an uncommon complication of posturological...
We present here a case of severe dyspnea after a percutaneous nephrostolithotomy, which resulted from an urinothorax, an uncommon complication of posturological procedures. Chest X-ray indicated a significant left pleural effusion, and a diagnosis was confirmed by the pleural fluid analysis. Chest tube placement did not improve the patient's clinical status; retrograde pyelogram was performed, and a stent was placed in the left ureter orifice where a narrowing was discovered. Correcting the cause of the urinothorax is the key in such cases of severe pleural effusions as seen in our case.
PubMed: 31334200
DOI: 10.4103/jfmpc.jfmpc_28_17 -
WMJ : Official Publication of the State... Sep 2023Trimethoprim-sulfamethoxazole (TMP-SMX) and phenazopyridine are individually associated with methemoglobinemia through a series of altered reduction-oxidation reactions....
A Case That Will Take Your Breath Away: Acquired Methemoglobinemia Related to Trimethoprim-Sulfamethoxazole and Phenazopyridine Ingestion for Treatment of Urinary Tract Infection.
Trimethoprim-sulfamethoxazole (TMP-SMX) and phenazopyridine are individually associated with methemoglobinemia through a series of altered reduction-oxidation reactions. We report a case of methemoglobinemia associated with concurrent use of TMP/SMX and phenazopyridine in a 70-year-old woman with recurrent urinary tract infections. She presented to the emergency department for worsening back pain in the setting of recurrent urinary tract infections, concerning for pyelonephritis. During her workup, she became acutely hypoxic. The emergency department provider suspected the presence of abnormal hemoglobin. An arterial blood gas showing elevated levels of methemoglobinemia confirmed the suspicion. The combined use of TMP/SMX and phenazopyridine was thought to be the likely etiology of hypoxia. This case highlights the importance of medication management in the geriatric population, as well as the judicious use of antibiotics for urinary tract infections-a common chief complaint in the primary care setting.
Topics: Aged; Female; Humans; Trimethoprim, Sulfamethoxazole Drug Combination; Phenazopyridine; Methemoglobinemia; Urinary Tract Infections; Eating
PubMed: 37768772
DOI: No ID Found -
Journal of Chromatographic Science 2016In this study, two analytical approaches were exploited for the resolution of binary mixtures of ciprofloxacin HCl (CIP) or norfloxacin (NOR) and phenazopyridine HCl...
Derivative Quotient Spectrophotometry and an Eco-Friendly Micellar Chromatographic Approach with Time-Programmed UV-Detection for the Separation of Two Fluoroquinolones and Phenazopyridine.
In this study, two analytical approaches were exploited for the resolution of binary mixtures of ciprofloxacin HCl (CIP) or norfloxacin (NOR) and phenazopyridine HCl (PHZ). In the first approach, the amplitudes of the first derivative of the ratio spectra were measured at 267 or 287 nm for CIP and at 268 or 291 nm for NOR. PHZ could be directly determined in the presence of CIP or NOR at 405 nm. The calibration graphs were rectilinear over the ranges of 1.0-16.0 µg/mL for CIP or NOR and 1.0-10.0 µg/mL for PHZ. In the second approach, an accurate, reliable and environmentally nontoxic micellar liquid chromatographic (MLC) method was developed. A good chromatographic separation was achieved using a 150 mm × 4.6 mm i.d., 5 µm particle size Spherisorb ODS-2 column. Eco-friendly mobile phase containing 0.12 M sodium dodecyl sulphate, 0.3% triethylamine and 6%n-butanol in 0.02 M orthophosphoric acid of pH 3.0 was pumped at a flow rate of 1 mL/min. Time programmed UV-detection was applied to allow sensitive determination of the studied drugs. The analytes were eluted without interferences in <10 min. Methocarbamol was used as an internal standard. The MLC method was found to be rectilinear over the concentration range of 0.5-20.0 μg/mL for CIP, NOR or PHZ. These optimized and validated methods were successfully applied for the simultaneous analysis of the studied drugs in their synthetic mixtures and co-formulated tablets. Moreover, the second method was further extended to the determination of these drugs in human urine with direct injection and without any pretreatment.
Topics: Chromatography, High Pressure Liquid; Fluoroquinolones; Micelles; Phenazopyridine; Spectrophotometry, Ultraviolet
PubMed: 26867555
DOI: 10.1093/chromsci/bmw010 -
Journal of AOAC International Sep 2017HPLC method was developed for the selective determination of phenazopyridine hydrochloride (PAP) in the presence of its computationally selected metabolite. Density...
HPLC method was developed for the selective determination of phenazopyridine hydrochloride (PAP) in the presence of its computationally selected metabolite. Density functional theory was applied as a computational model to study the energy of PAP metabolites, and the results revealed that 2,3,6-triaminopyridine (TAP) is the most stable metabolite. Good resolution and separation of PAP from TAP was achieved using a reversed-phase BDS Hypersil C18 column with a mobile phase consisting of acetonitrile-water (75 + 25, v/v) at flow rate of 1 mL/min and with UV detection at 280 nm. The linear regression analysis data for the calibration plot of PAP showed a good linear relationship over the concentration range of 5-45 μg/mL, with an LOD of 0.773 μg/mL. Moreover, a theoretical investigation of the relationship between the stationary phase and the studied molecules was performed to confirm the experimental results. The proposed method was successfully applied for the selective determination of PAP in pharmaceutical formulation. In addition, the obtained results were statistically compared to a reported method, with no significant differences found between the investigated method and the reported one with respect to accuracy and precision.
Topics: Calibration; Chemistry, Pharmaceutical; Chromatography, High Pressure Liquid; Phenazopyridine
PubMed: 28421989
DOI: 10.5740/jaoacint.16-0301 -
Archives of Biochemistry and Biophysics Jul 2024Drug metabolism by human gut microbes is often exemplified by azo bond reduction in the anticolitic prodrug sulfasalazine. Azoreductase activity is often found in...
Drug metabolism by human gut microbes is often exemplified by azo bond reduction in the anticolitic prodrug sulfasalazine. Azoreductase activity is often found in incubations with cell cultures or ex vivo gut microbiome samples and contributes to the xenobiotic metabolism of drugs and food additives. Applying metagenomic studies to personalized medicine requires knowledge of the genes responsible for sulfasalazine and other drug metabolism, and candidate genes and proteins for drug modifications are understudied. A representative gut-abundant azoreductase from Anaerotignum lactatifermentan DSM 14214 efficiently reduces sulfasalazine and another drug, phenazopyridine, but could not reduce all azo-bonded drugs in this class. We used enzyme kinetics to characterize this enzyme for its NADH-dependent reduction of these drugs and food additives and performed computational docking to provide the groundwork for understanding substrate specificity in this family. We performed an analysis of the Flavodoxin-like fold InterPro family (IPR003680) by computing a sequence similarity network to classify distinct subgroups of the family and then performed chemically-guided functional profiling to identify proteins that are abundant in the NIH Human Microbiome Project dataset. This strategy aims to reduce the number of unique azoreductases needed to characterize one protein family in the diverse set of potential drug- and dye-modifying activities found in the human gut microbiome.
Topics: Humans; Nitroreductases; Gastrointestinal Microbiome; NADH, NADPH Oxidoreductases; Coloring Agents; Molecular Docking Simulation; Substrate Specificity; Sulfasalazine; Bacterial Proteins; Kinetics; Clostridiales; Azo Compounds
PubMed: 38740275
DOI: 10.1016/j.abb.2024.110025