Appeals in Workmen\u27s Compensation

There is a solution to the problem of appeals in the Ohio Workmen\u27s Compensation Act. Permit the administrative officers who are well trained and have many years of experience to determine the facts and law with court appeals on questions of law only. Since Ohio is a State Fund operation, hearing officers probably should not be responsibleto the Bureau of Workmen\u27s Compensation. This alliance could affect their judgment since they must defend the insurance fund against any claim which is, in their opinion, unlawful

Cationic amphiphilic drugs cause a marked expansion of apparent lysosomal volume: Implications for an intracellular distribution-based drug interaction

How a drug distributes within highly compartmentalized mammalian cells can affect both the activity and pharmacokinetic behavior. Many commercially available drugs are considered to be lysosomotropic, meaning they are extensively sequestered in lysosomes by an ion trapping-type mechanism. Lysosomotropic drugs typically have a very large apparent volume of distribution and a prolonged half-life in vivo, despite minimal association with adipose tissue. In this report we tested the prediction that the accumulation of one drug (perpetrator) in lysosomes could influence the accumulation of a secondarily administered one (victim), resulting in an intracellular distribution-based drug interaction. To test this hypothesis cells were exposed to nine different hydrophobic amine-containing drugs, which included imipramine, chlorpromazine and amiodarone, at a 10 µM concentration for 24 to 48 hours. After exposure to the perpetrators the cellular accumulation of LysoTracker Red (LTR), a model lysosomotropic probe, was evaluated both quantitatively and microscopically. We found that all of the tested perpetrators caused a significant increase in the cellular accumulation of LTR. Exposure of cells to imipramine caused an increase in the cellular accumulation of other lysosomotropic probes and drugs including LyosTracker Green, daunorubicin, propranolol and methylamine; however, imipramine did not alter the cellular accumulation of non-lysosomotropic amine-containing molecules including MitoTracker Red and sulforhodamine 101. In studies using ionophores to abolish intracellular pH gradients we were able to resolve ion trapping-based cellular accumulation from residual pH-gradient independent accumulation. Results from these evaluations in conjunction with lysosomal pH measurements enabled us to estimate the relative aqueous volume of lysosomes of cells before and after imipramine treatment. Our results suggest that imipramine exposure caused a 4-fold expansion in the lysosomal volume, which provides the basis for the observed drug interaction. The imipramine-induced lysosomal volume expansion was shown to be both time- and temperature-dependent and reversed by exposing cells to hydroxypropyl-β-cyclodextrin, which reduced lysosomal cholesterol burden. This suggests that the expansion of lysosomal volume occurs secondary to perpetrator-induced elevations in lysosomal cholesterol content. In support of this claim, the cellular accumulation of LTR was shown to be higher in cells isolated from patients with Niemann-Pick Type C disease, which are known to hyper-accumulate cholesterol in lysosomes

Preparing and organizing results from an ENU mutagenesis screen for congenital heart disease for public view

Congenital heart disease (CHD) is one of the most common birth defects in humans. In addition, CHD is the leading cause of infant death. Ethylnitrosourea (ENU) is used to induce random single nucleotide polymorphisms in mice. Once the mice are have a mutation they are sent to the University of Pittsburgh for analysis to determine if the SNP is associated with cardiovascular defects. Each mutated mouse is used to breed its own mouse line. The ENU screen uses echocardiography, EFIC imaging, necropsy and exome sequencing to determine the phenotypes and genotypes of the mouse lines. The screen has identified novel genes in mice that may be potential causes of CHD in infants. The Bench to Bassinet program is a nationwide program that translates basic science to clinical trials. As part of this program, data gathered by the ENU screen in mice is organized and available to the public through Jackson Labs Mouse Genome Informatics Database. As of March 2013, 123 mouse lines covering many different types of cardiovascular and craniofacial defects have been made available to the public. Public health significance: Approximately 40,000 infants die from CHD each year. This research and this database enables collaboration among many researchers to identify the causal genes of CHD in infants, and hopefully an eventual means of prophylaxis

cIBR effectively targets nanoparticles to LFA-1 on acute lymphoblastic T cells

Leukocyte function associated antigen-1 (LFA-1) is a primary cell adhesion molecule of leukocytes required for mediating cellular transmigration into sites of inflammation via the vascular endothelium. A cyclic peptide, cIBR, possesses high affinity for LFA-1 and conjugation to the surface of poly(dl-lactic-co-glycolic acid) nanoparticles can specifically target and deliver the encapsulated agents to T cells expressing LFA-1. The kinetics of targeted nanoparticle uptake by acute lymphoblastic leukemia T cells was investigated by flow cytometry and microscopy and compared to untargeted nanoparticles. The specificity of targeted nanoparticles binding to the LFA-1 integrin was demonstrated by competitive inhibition using free cIBR peptide or using the I domain of LFA-1 to inhibit the binding of targeted nanoparticles. The uptake of targeted nanoparticles was concentration and energy dependent. The cIBR-conjugated nanoparticles did not appear to localize with lysosomes whereas untargeted nanoparticles were detected in lysosomes in 6 hrs and steadily accumulated in lysosomes for 24 hrs. Finally, T-cell adhesion to epithelial cells was inhibited by cIBR-nanoparticles. Thus, nanoparticles displaying the cIBR ligand may offer a useful targeted drug delivery system as an alternative treatment of inflammatory diseases involving transmigration of leukocytes

Lysosomotropic Properties of Weakly Basic Anticancer Agents Promote Cancer Cell Selectivity In Vitro

A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author’s publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Drug distribution in cells is a fundamentally important, yet often overlooked, variable in drug efficacy. Many weakly basic anticancer agents accumulate extensively in the acidic lysosomes of normal cells through ion trapping. Lysosomal trapping reduces the activity of anticancer drugs, since anticancer drug targets are often localized in the cell cytosol or nucleus. Some cancer cells have defective acidification of lysosomes, which causes a redistribution of trapped drugs from the lysosomes to the cytosol. We have previously established that such differences in drug localization between normal and cancer cells can contribute to the apparent selectivity of weakly basic drugs to cancer cells in vitro. In this work, we tested whether this intracellular distribution-based drug selectivity could be optimized based on the acid dissociation constant (pKa) of the drug, which is one of the determinants of lysosomal sequestration capacity. We synthesized seven weakly basic structural analogs of the Hsp90 inhibitor geldanamycin (GDA) with pKa values ranging from 5 to 12. The selectivity of each analog was expressed by taking ratios of anti-proliferative IC50 values of the inhibitors in normal fibroblasts to the IC50 values in human leukemic HL-60 cells. Similar selectivity assessments were performed in a pair of cancer cell lines that differed in lysosomal pH as a result of siRNA-mediated alteration of vacuolar proton ATPase subunit expression. Optimal selectivity was observed for analogs with pKa values near 8. Similar trends were observed with commercial anticancer agents with varying weakly basic pKa values. These evaluations advance our understanding of how weakly basic properties can be optimized to achieve maximum anticancer drug selectivity towards cancer cells with defective lysosomal acidification in vitro. Additional in vivo studies are needed to examine the utility of this approach for enhancing selectivity

Effect of modification of the physicochemical properties of ICAM-1-derived peptides on internalization and intracellular distribution in the human leukemic cell line HL-60

The objective of this work is to test the hypothesis that increasing the hydrophilicity of DOX−peptide conjugates may modify their entry mechanisms into HL-60 cells from passive diffusion to receptor-mediated uptake. To test this hypothesis, the entry mechanisms and the intracellular disposition of DOX−cIBR7, DOX−PEGcIBR7, FITC−cIBR, and FITC−cIBR7 were evaluated in HL-60 cells. To increase the hydrophilicity of the peptide, the cIBR peptide (cyclo(1,12)PenPRGGSVLVTGC) was modified to cIBR7 peptide (cyclo(1,8)CPRGGSVC) by removing the hydrophobic residues at the C-terminus. DOX−cIBR7 conjugate, which has higher hydrophilicity than DOX−cIBR, was synthesized. Second, a hydrophilic linker (11-amino-3,6,9-trioxaundecanate linker) was incorporated between DOX and cIBR7 to generate DOX−PEGcIBR7 with higher hydrophilicity than DOX−cIBR7. As controls, FITC−cIBR and FITC−cIBR7 were used to check for any endocytic uptake process of the peptide. As previously found with DOX−cIBR, DOX−cIBR7, and DOX−PEGcIBR7, conjugates enter the cells via passive diffusion and not via the energy-dependent endocytic process. This result suggests that an increase in hydrophilicity does not influence the entry mechanism of the DOX−peptide conjugates. In contrast to the DOX−cIBR7 conjugate, the FITC−cIBR7 conjugate showed energy-dependent cellular entry into the cells and followed an endocytic pathway similar to that for dextran. Finally, the entry of DOX−cIBR7 and DOX−PEGcIBR into the cell cytosol was shown to be due to the properties of DOX and not to those of the peptide

Uptake, Distribution and Diffusivity of Reactive Fluorophores in Cells: Implications Toward Target Identification

There is much recent interest in the application of copper-free click chemistry to study a wide range of biological events in vivo and in vitro. Specifically, azide-conjugated fluorescent probes can be used to identify targets which have been modified with bioorthogonal reactive groups. For intracellular applications of this chemistry, the structural and physicochemical properties of the fluorescent azide become increasingly important. Ideal fluorophores should extensively accumulate within cells, have even intracellular distribution, and be free (unbound), allowing them to efficiently participate in bimolecular reactions. We report here on the synthesis and evaluation a set of structurally diverse fluorescent probes to examine their potential usefulness in intracellular click reactions. Total cellular uptake and intracellular distribution profiles were comparatively assessed using both quantitative and qualitative approaches. The intracellular diffusion coefficients were measured using a fluorescence recovery after photobleaching (FRAP)-based method. Many reactive fluorophores exhibited suboptimal properties for intracellular reactions. BODIPY- and TAMRA-based azides had superior cellular accumulation, whereas TAMRA-based probes had the most uniform intracellular distribution and best cytosolic diffusivity. Collectively, these results provide an unbiased comparative evaluation regarding the suitability of azide-linked fluorophores for intracellular click reactions

Autocuidado de enfermeras durante la pandemia COVID-19, de un Centro de Salud del MINSA. Chiclayo 2021

Las enfermeras tienen responsabilidad tanto personal como profesional en promover su autocuidado, ya que son agentes que fomentan conductas positivas de salud; motivo por el cual se realizó la investigación, con el objetivo de caracterizar el autocuidado de enfermeras durante la pandemia COVID-19. El estudio fue cualitativo, con abordaje estudio de caso. La población estuvo conformada por 15 enfermeras y la muestra por siete, la cual fue delimitada por saturación. Para la recolección de datos se utilizó la entrevista y como instrumento una guía de entrevista abierta a profundidad, validado por juicio de tres expertos y mediante la prueba piloto. La información obtenida fue procesada a través del análisis de contenido, surgiendo las siguientes categorías: “Adoptando medidas preventivas para evitar contagiarse de la COVID-19”, “Intentando satisfacer sus necesidades biofísicas para el cuidado de su salud” y “Afrontando sus sentimientos y emociones generadas por la COVID-19”. Como consideración final se revela que el autocuidado de las enfermeras estuvo dirigido a evitar contagiarse del virus SARS-CoV-2 haciendo uso de medidas básicas de bioseguridad; y a realizar actividades de cuidado para satisfacer sus necesidades de alimentación, hidratación y reposo; teniendo relevancia su autocuidado emocional, social y espiritual

A Novel Drug Modulator Diarylheptanoid (trans-1,7-Diphenyl-5-hydroxy-1-heptene) from Curcuma comosa Rhizomes for P-glycoprotein Function and Apoptosis Induction in K652/ADR Leukemic Cells

Curcuma comosa has been used in traditional Thai medicine to treat menstrual cycle-related symptoms in women. This study aims to evaluate the diarylheptanoid drug modulator, trans-1,7-diphenyl-5-hydroxy-1-heptene (DHH), in drug-resistant K562/ADR human leukemic cells. This compound was studied due to its effects on cell cytotoxicity, multidrug resistance (MDR) phenotype, P-glycoprotein (P-gp) expression, and P-gp function. We show that DHH itself is cytotoxic towards K562/ADR cells. However, DHH did not impact P-gp expression. The impact of DHH on the MDR phenotype in the K562/ADR cells was determined by co-treatment of cells with doxorubicin (Dox) and DHH using an MTT assay. The results showed that the DHH changed the MDR phenotype in the K562/ADR cells by decreasing the IC50 of Dox from 51.6 to 18.2 µM. Treating the cells with a nontoxic dose of DHH increased their sensitivity to Dox in P-gp expressing drug-resistant cells. The kinetics of P-gp mediated efflux of pirarubicin (THP) was used to monitor the P-gp function. DHH was shown to suppress THP efflux and resulted in enhanced apoptosis in the K562/ADR cells. These results demonstrate that DHH is a novel drug modulator of P-gp function and induces drug accumulation in the Dox-resistant K562 leukemic cell line

Separate Roles for the Golgi Apparatus and Lysosomes in the Sequestration of Drugs in the Multidrug-resistant Human Leukemic Cell Line HL-60

The sequestration of drugs away from cellular target sites into cytoplasmic organelles of multidrug-resistant (MDR) cancer cells has been recently shown to be a cause for ineffective drug therapy. This process is poorly understood despite the fact that it has been observed in a large number of MDR cancer cell lines. Analysis of drug sequestration in these cells has traditionally been done using fluorescent anthracycline antibiotics (i.e. daunorubicin, doxorubicin). This narrow selection of substrates has resulted in a limited understanding of sequestration mechanisms and the intracellular compartments that are involved. To better characterize this phenotype, we chose to examine the sequestration of molecules having different acid/base properties in the MDR HL-60 human leukemic cell line. Here we show that weakly basic drug daunorubicin is sequestered into lysosomes according to a pH partitioning type mechanism, whereas sulforhodamime 101, a zwitterionic molecule, is sequestered into the Golgi apparatus through a drug transporter-mediated process. Quantitative intracellular pH measurements reveal that the lysosome-tocytosol pH gradient is expanded in the MDR line. Moreover, the MDR cells overexpress the multidrug resistance-related protein (MRP1), which is localized to the Golgi apparatus. These results demonstrate, for the first time, that two distinct mechanisms for intracellular compartmentalization are operational in a single MDR cell line