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Environmental Health Perspectives Feb 1997
Topics: Animals; Birth Weight; Body Weight; Cathartics; Dose-Response Relationship, Drug; Epididymis; Female; Fertility; Litter Size; Male; Mice; Organ Size; Phenolphthalein; Phenolphthaleins; Pregnancy; Reproduction; Seminiferous Tubules; Sperm Count; Spermatozoa; Testis
PubMed: 9114350
DOI: No ID Found -
Indian Journal of Ophthalmology Sep 2023This case series highlights the challenges in eye banking and the importance of a quality assurance program. Three cases triggered corrective and preventive actions...
This case series highlights the challenges in eye banking and the importance of a quality assurance program. Three cases triggered corrective and preventive actions (CAPAs) to improve the processes. Case 1 emphasized training to prevent retrieval failures. Case 2 stressed the need for blood samples and comprehensive documentation. In Case 3, mishandling led to policy revisions and staff training. CAPA involved identifying concerns, root cause analysis, action plans, implementation, checks, and closure. Errors can occur in man, machinery, process, and policies. Continuous CAPA ensures continuous quality improvement and safe corneal tissue transplantation, benefiting patients in need.
Topics: Humans; Eye Banks; Corneal Transplantation; Cornea; Dioctyl Sulfosuccinic Acid; Phenolphthalein
PubMed: 37602597
DOI: 10.4103/IJO.IJO_1994_23 -
Biotechnology For Biofuels Feb 2021Lytic polysaccharide monooxygenases (LPMOs) are important industrial enzymes known for their catalytic degradation of recalcitrant polymers such as cellulose or chitin....
BACKGROUND
Lytic polysaccharide monooxygenases (LPMOs) are important industrial enzymes known for their catalytic degradation of recalcitrant polymers such as cellulose or chitin. Their activity can be measured by lengthy HPLC methods, while high-throughput methods are less specific. A fast and specific LPMO assay would simplify screening for new or engineered LPMOs and accelerate biochemical characterization.
RESULTS
A novel LPMO activity assay was developed based on the production of the dye phenolphthalein (PHP) from its reduced counterpart (rPHP). The colour response of rPHP oxidisation catalysed by the cellulose-specific LPMO from Thermoascus aurantiacus (TaAA9A), was found to increase tenfold by adding dehydroascorbate (DHA) as a co-substrate. The assay using a combination of rPHP and DHA was tested on 12 different metallo-enzymes, but only the LPMOs catalysed this reaction. The assay was optimized for characterization of TaAA9A and showed a sensitivity of 15 nM after 30 min incubation. It followed apparent Michaelis-Menten kinetics with k = 0.09 s and K = 244 µM, and the assay was used to confirm stoichiometric copper-enzyme binding and enzyme unfolding at a temperature of approximately 60 °C. DHA, glutathione and fructose were found to enhance LPMO oxidation of rPHP and in the optimized assay conditions these co-substrates also enabled cellulose degradation.
CONCLUSIONS
This novel and specific LPMO assay can be carried out in a convenient microtiter plate format ready for high-throughput screening and enzyme characterization. DHA was the best co-substrate tested for oxidation of rPHP and this preference appears to be LPMO-specific. The identified co-substrates DHA and fructose are not normally considered as LPMO co-substrates but here they are shown to facilitate both oxidation of rPHP and degradation of cellulose. This is a rare example of a finding from a high-throughput assay that directly translate into enzyme activity on an insoluble substrate. The rPHP-based assay thus expands our understanding of LPMO catalysed reactions and has the potential to characterize LPMO activity in industrial settings, where usual co-substrates such as ascorbate and oxygen are depleted.
PubMed: 33640002
DOI: 10.1186/s13068-021-01902-4 -
Orthopadie (Heidelberg, Germany) Sep 2023More than almost any other implant, fully implantable intramedullary distraction nails have changed corrective and reconstructive bone surgery. Based on the fundamentals... (Review)
Review
More than almost any other implant, fully implantable intramedullary distraction nails have changed corrective and reconstructive bone surgery. Based on the fundamentals of callus distraction, these new apparatus developments with their novel planning strategies and minimally invasive surgical techniques have opened up a wide range of indications and made the treatment reproducible and safe. The prerequisite, however, is that standardized procedures are adhered to, which concern both the preparation for the surgery, the surgery itself and the subsequent distraction treatment. Treatment with fully implantable intramedullary distraction nails should be performed at specialized centers, so that the paradigm shift in corrective and reconstructive limb surgery, which is already recognizable, will open the door for further developments.
Topics: Nails; Internal Fixators; Fracture Fixation, Intramedullary; Prostheses and Implants; Bone Lengthening; Dioctyl Sulfosuccinic Acid; Phenolphthalein
PubMed: 37620678
DOI: 10.1007/s00132-023-04418-x -
Molecules (Basel, Switzerland) Nov 2021Weight loss supplements that have illegal additives of pharmaceutical drugs or analogues have additional health risks, and customers may not be aware of what they are...
Weight loss supplements that have illegal additives of pharmaceutical drugs or analogues have additional health risks, and customers may not be aware of what they are taking. This research is an essential investigation and quantification of illegally added pharmaceuticals or prescription medications, specifically fluoxetine, phenolphthalein, and sibutramine, in herbal weight loss supplements offered for sale in the United Arab Emirates (UAE). In this case, 137 weight loss supplements were collected and analyzed in this study. Reversed-phase high-performance liquid chromatography with UV absorption detection coupled to tandem mass spectrometry (RP-HPLC-MS/MS) analyses were used to determine the presence of the pharmaceutical chemicals. Among the weight loss supplements, 15.3% (95% CI: 9.2-21.4) contained undeclared sibutramine, 13.9% (95% CI: 8.01-19.7) contained undeclared phenolphthalein, and 5.1% (95% CI: 1.4-8.8) contained undeclared fluoxetine. Amongst all weight loss supplements, 17.5% (95% CI: 11.07-24) contained significant concentrations of either sibutramine, phenolphthalein, or fluoxetine. Whilst weight loss herbal supplements offered for sale in the UAE have relatively low percentages of undeclared pharmaceuticals, many people take several different supplements daily and may encounter quite high levels of combined exposure to toxic compounds.
Topics: Anti-Obesity Agents; Chromatography, High Pressure Liquid; Dietary Supplements; Drug Contamination; Humans; Tandem Mass Spectrometry; United Arab Emirates
PubMed: 34833995
DOI: 10.3390/molecules26226903 -
Polymers Feb 2024Aluminum butylmethylphosphinate AiBMP as a flame retardant and phenolphthalein as a synergistic agent were applied in a thermoplastic polyester elastomer (TPEE)) in the...
Aluminum butylmethylphosphinate AiBMP as a flame retardant and phenolphthalein as a synergistic agent were applied in a thermoplastic polyester elastomer (TPEE)) in the current study. The thermal properties, flame retardancy, crystallization and mechanical properties of TPEE/AiMBP with or without phenolphthalein were investigated using various characterizations, including the limiting oxygen index (LOI), vertical burning test (UL 94), thermogravimetric analysis TG, differential scanning calorimetry, microcombustion calorimeter (MCC), scanning electron microscopy (SEM), and mechanical tests. The results revealed that AiBMP alone is an efficient flame retardant of TPEE. Adding 15 wt.% AiBMP increases the LOI value of TPEE from 20% to 36%. The formula TPEE-15 AiBMP passed the UL 94 V-0 rating with no dripping occurring. The MCC test shows that AiBMP depresses the heat release of TPEE. In comparison with pure TPEE, the heat release rate at peak temperature and the heat release capacity of TPEE-15AiBMP are reduced by 46.1% and 55.5%, respectively. With the phenolphthalein added, the formula TPEE/13AiBMP/2Ph shows a higher char yield at high temperatures (>600 °C), and the char layer is stronger and more condensed than TPEE-15AiBMP.The tensile strength and elongation at break values of TPEE-13AiBMP-2Ph are increased by 29.63% and 4.8% in comparison with TPEE-15AiBMP. The SEM morphology of the fracture surface of the sample shows that phenolphthalein acts as a plasticizer to improve the dispersion of AiBMP within the matrix. The good char charming ability of phenolphthalein itself and improved dispersion of AiBMP make the TPEE composites achieve both satisfying flame retardancy and high mechanical properties.
PubMed: 38399930
DOI: 10.3390/polym16040552 -
Vaccine Jan 2023Amid the COVID-19 pandemic, the scientific community has been understandably eager to combat misinformation about issues such as vaccine safety. In highly polarized...
Amid the COVID-19 pandemic, the scientific community has been understandably eager to combat misinformation about issues such as vaccine safety. In highly polarized information environments, however, even well-intentioned messages have the potential to produce adverse effects. In this study, we connect different disciplinary strands of social science to derive and experimentally test the novel hypothesis that although particular efforts to debunk misinformation about mRNA vaccines will reduce relevant misperceptions about that technology, these correctives will harm attitudes toward other types of vaccines. We refer to this as the "collateral damage hypothesis." Our study specifically examines a corrective message stating that "mRNA vaccines do not contain live virus," and our results offer some support for our hypothesis, with the corrective triggering increased societal risk perceptions of live vaccines. We also find that the effect is, predictably, most evident among those whose vaccine acceptance is low. Building on the theoretical grounding we outline, we test a "damage control" adjustment to the corrective message and present evidence supporting that it mitigates the collateral damage.
Topics: Humans; Pandemics; COVID-19; Dioctyl Sulfosuccinic Acid; Drug-Related Side Effects and Adverse Reactions; Phenolphthalein; mRNA Vaccines; Communication
PubMed: 36682880
DOI: 10.1016/j.vaccine.2022.12.045 -
Sensors (Basel, Switzerland) Oct 2022In this work, a coulometer was developed from a digitally controlled galvanostat. A simple colorimeter based on a RGB LED was used as a light emitter coupled to light...
In this work, a coulometer was developed from a digitally controlled galvanostat. A simple colorimeter based on a RGB LED was used as a light emitter coupled to light detectors, while light dependent resistance (LDR) and photodiodes have been developed as endpoint detectors. Both hardware and software have been adapted from the original galvanostat design. Regarding the hardware, new electrical signal conditioners (filters and voltage dividers) were included to optimize the working system. The software was developed based on an open source Arduino UNO microcontroller. The different variables that control the titration process are managed by an add-in module for Excel data acquisition software that is freely available. A study of the possible variables that influence the titration process has been carried out. The system was tested with two classical coulometric titrations such as iodometry (thiosulfate, ascorbic acid) and acid/base (potassium acid phthalate as standard). The developed system is versatile as different endpoint color indicators can be employed (starch and phenolphthalein for the investigated reactions). Different experimental arrangements have been studied: the nature of the electrodes (Pt, Ag), type of cells (two separate compartments or a single compartment), and light detectors (LDR, photodiode). The influence of several experimental parameters (both electrical, light, and integration time) was studied and chosen to obtain the best performance of the complete system. Reproducibility results below 1% can be obtained under controlled conditions. In the case of acid/base titrations, the presence of atmospheric carbon dioxide was detected, whose interference was mainly affected by the stirring rate and the titration time.
Topics: Ascorbic Acid; Carbon Dioxide; Phenolphthaleins; Potassium; Reproducibility of Results; Starch; Thiosulfates
PubMed: 36236640
DOI: 10.3390/s22197541 -
Pharmaceutical Biology Dec 2023Linnaeus (Bombacaceae) is known as silk cotton tree, the flowers of which are used in many medicinal applications.
CONTEXT
Linnaeus (Bombacaceae) is known as silk cotton tree, the flowers of which are used in many medicinal applications.
OBJECTIVE
To investigate the therapeutic effect of flower aqueous extracts (BCE) against loperamide-induced constipation and characterize the chemical composition of BCE.
MATERIALS AND METHODS
Sixty male Kunming mice were divided into control (saline), model (10 mg/kg loperamide + saline), phenolphthalein (10 mg/kg loperamide + 10 mg/kg phenolphthalein) and different dosage of BCE (10 mg/kg loperamide + 40, 80 and 160 mg/kg BCE, respectively) groups, and received intragastric administrations for eight days. Faecal water content, number of faeces, first black-stool defecation time and gastrointestinal transit rates were evaluated. Various biochemical and molecular biomarkers were assessed in blood and colon. UPLC-ESI-QTOF-MS/MS was used to tentatively identify the composition of the BCE.
RESULTS
BCE treatment (160 mg/kg) could increase faecal water (15.75%), faeces number (11.65%), gastrointestinal transit rate (25.37%) and decrease first black-stool defecation time (24.04%). The BCE (80 mg/kg) increased the serum level of motilin (30.62%), gastrin (54.46%) and substance P (18.99%), and decreased somatostatin (19.47%). Additionally, the BCE (160 mg/kg) reduced the mucosal damage, restored colonic goblet cell function, down-regulated the protein expression of AQP (33.60%) and increased c-kit protein expression (11.63%). Twelve known compounds, including protocatechuic acid, chlorogenic acid and rutin, previously reported in were identified in the BCE.
DISCUSSION AND CONCLUSIONS
This study suggested that BCE is a promising agent for the treatment of constipation.
Topics: Mice; Animals; Loperamide; Bombax; Tandem Mass Spectrometry; Constipation; Flowers; Water; Phenolphthaleins
PubMed: 36582187
DOI: 10.1080/13880209.2022.2157841 -
Polymers Sep 2022As an alternative to traditional riveting and welding materials, high-temperature-resistant adhesives, with their unique advantages, have been widely used in aviation,...
As an alternative to traditional riveting and welding materials, high-temperature-resistant adhesives, with their unique advantages, have been widely used in aviation, aerospace, and other fields. Among them, polyimide (PI) adhesives have been one of the most studied species both from basic and practical application aspects. However, in the main applications of solvent-type PI adhesives, pinholes or bubbles often exist in the cured PI adhesive layers due to the solvent volatilization and dehydration reaction, which directly affect the adhesive performance. To address this issue, electrospun PI nanofibrous membranes (NFMs) were employed as solvent-free or solvent-less adhesives for stainless steel in the current work. To enhance the adhesion of PI adhesives to the metal substrates, phenolphthalein groups and flexible ether bonds were introduced into the main chain of PIs via the monomers of 4,4'-oxydiphthalic anhydride (ODPA) and 3,3-bis[4-(4-aminophenoxy)phenyl] phthalide (BAPPT). At the same time, the methylethynyl group was used as the end-capping component, and the crosslinking reaction of the alkynyl group at high temperature further increased the adhesive strength of the PI adhesives. Three kinds of methylethynyl-terminated PI (METI) NFMs with the set molecular weights of 5000, 10,000, and 20,000 g/mol were first prepared via the one-step high-temperature polycondensation procedure. Then, the PI NFMs were fabricated via the standard electrospinning procedure from the soluble METI solutions. The afforded METI NFMs showed excellent melt-flowing behaviors at high temperature. Incorporation of the methylethynyl end-capping achieved a crosslinking reaction at 280-310 °C for the NFMs, which was about 70 °C lower than those of the phenylacetylene end-capping counterparts. Using the METI NFMs as adhesive, stainless steel adherends were successfully bonded, and the single-lap shear strength (LSS) was higher than 20.0 MPa at both room temperature (25 °C) and high temperature (200 °C).
PubMed: 36236026
DOI: 10.3390/polym14194078