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High-risk neuroblastoma continues to carry a poor prognosis. Nearly 50% of these tumors relapse following extensive treatment regimens. Protein phosphatase 2A (PP2A), a tumor suppressor, has been shown to be downregulated in many human cancers via multiple mechanisms including upregulation of its endogenous inhibitors, I2PP2A or CIP2A. We hypothesized that inhibition of the endogenous PP2A inhibitors or activation of PP2A would decrease tumorigenicity in human neuroblastoma cells. Four human neuroblastoma cell lines were utilized. Expression of PP2A and its endogenous inhibitors I2PP2A and CIP2A was confirmed by immunoblotting. PP2A activation was measured via phosphatase activation assay. Multiple parallel methods including siRNA inhibition of the endogenous PP2A inhibitors and pharmacologic activation of PP2A were utilized. Cell viability, proliferation, migration, and invasion assays were performed. In vivo studies were utilized to determine the effects of PP2A activation on neuroblastoma tumor growth. Inhibition of the endogenous inhibitors of PP2A or pharmacologic activation of PP2A with the PP2A activator FTY720 led to decreased neuroblastoma cell viability, proliferation, migration, and invasion. Treatment of mice bearing SK-N-AS or SK-N-BE(2) neuroblastoma tumors with FTY720 resulted in a significant decrease in tumor growth compared to vehicle-treated animals. In conclusion, activation of PP2A may provide a novel therapeutic target for neuroblastoma.

Knee arthroscopy has allowed us to continue performing surgeries that are minimally invasive and allow patients to have a quick recovery. Multiligamentous knee reconstruction with regards to the anterior cruciate ligament and posterior cruciate ligament can be done in a minimally invasive matter. Visualization is an issue during this surgery, especially looking in the posterior compartment of the knee. The NanoScope (Arthrex, Naples, FL) continues to provide increased possibilities for orthopaedic surgeons. Our technique provides a less-invasive way to observe the posterior compartment to assist the drilling of the tibial tunnel during the posterior cruciate ligament reconstruction. This technique provides distinct advantages over other treatments., (© 2021 by the Arthroscopy Association of North America. Published by Elsevier.)

Recent advancements in computer-assisted surgery have led to a renewed interest in robotic-assisted hip arthroplasty. This technology assists with component position which is especially useful in prior trauma or dysplasia cases. We present a case of a surgical hip fusion conversion to total hip arthroplasty with the use of robotic-assisted technology. Enhanced preoperative planning with the ability to manipulate implant position before execution can be invaluable during complex procedures. Further research is warranted before revision cases using computerized navigation systems becomes more prevalent.

Background: African Americans (AA) and socioeconomic status (SES) disadvantaged older breast cancer survivors (BCS) are more likely to experience poor functional and health outcomes. However, few studies have evaluated the putative beneficial effects of exercise on these outcomes in older racial minority and SES-disadvantaged BCS., Methods: This is a mixed-methods study that includes a randomized-controlled trial, "IMPROVE", to evaluate a group-based exercise intervention compared to a support group program in older BCS, followed by post-intervention semi-structured interviews to evaluate the intervention. The trial aims to recruit 220 BCS with 55 in each of four strata defined by race (AA versus Non-Hispanic Whites) and SES (disadvantaged vs. non-disadvantaged). Participants are ≥65 years old and within five years of treatment completion for stage I-III breast cancer. Participants are randomized to a 52-week, three sessions/week, one-hour/session, moderate intensity aerobic and resistance group exercise intervention, (n = 110) or a 52-week, one hour/week, support group intervention [attention-control arm], (n = 110). The first 20 weeks of both programs are supervised and the last 32 weeks, unsupervised. The primary outcome is the change in Short Physical Performance Battery (SPPB) Scores at 20 weeks from baseline, between the two arms. Secondary outcomes include change in SPPB scores at 52 weeks, change in body composition and biomarkers, at 20 and 52 weeks from baseline, between arms., Discussion: Results of the trial may contribute to a better understanding of factors associated with recruitment, and acceptability, and will inform future exercise programs to optimally improve health outcomes for older BCS., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Racial/ethnic disparities in tobacco cessation are such that U.S. minorities have greater difficulty quitting compared to White non-Hispanics. Group differences in distress (i.e., perceived stress and depressive symptoms) may contribute to cessation disparities. The allostasis model of health suggests that the toll of chronic stress experienced by racial/ethnic minorities may lead to dysregulation of the physiological stress system and drug use. Previous research suggests that group cognitive behavioral therapy (CBT) for tobacco cessation addresses distress as a modifiable mechanism and has the potential to reduce/eliminate disparities. The present study is a dualsite randomized controlled trial aimed at evaluating the efficacy of group CBT in eliminating racial/ethnic differences in smoking cessation and distress. The study utilizes a [2 (intervention: group CBT or group general health education [GHE]) × 3 (race/ethnicity: African American/Black, Hispanic, White)] factorial design by randomizing 225 adult smokers from the community. Both interventions provide eight counseling sessions and eight weeks of nicotine patch therapy. Assessments occur at the end-of-therapy, and at 3-, 6-, and 12-months. Generalized longitudinal mixed modeling will be used to test our primary abstinence outcome, biochemically-confirmed 7-day point prevalence abstinence at 12-months. We hypothesize that group CBT will reduce or eliminate racial/ethnic differences in perceived stress, depressive symptoms, and smoking cessation compared to group GHE. We also hypothesize that reductions in physiological distress, assessed by salivary cortisol, will mediate racial/ethnic group differences in smoking cessation, particularly among racial/ethnic minorities. This study has implications for eliminating disparities in psychosocial factors related to tobacco use and cessation., Trial Registration: Clinicaltrials.govNCT02511236. Registered on July 27, 2015., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The Oil Pollution Act of 1990 establishes liability for injuries to natural resources because of the release or threat of release of oil. Assessment of injury to natural resources resulting from an oil spill and development and implementation of a plan for the restoration, rehabilitation, replacement or acquisition of natural resources to compensate for those injuries is accomplished through the Natural Resource Damage Assessment (NRDA) process. The NRDA process began within a week of the Deepwater Horizon oil spill, which occurred on April 20, 2010. During the spill, more than 8500 dead and impaired birds representing at least 93 avian species were collected. In addition, there were more than 3500 birds observed to be visibly oiled. While information in the literature at the time helped to identify some of the effects of oil on birds, it was not sufficient to fully characterize the nature and extent of the injuries to the thousands of live oiled birds, or to quantify those injuries in terms of effects on bird viability. As a result, the US Fish and Wildlife Service proposed various assessment activities to inform NRDA injury determination and quantification analyses associated with the Deepwater Horizon oil spill, including avian toxicity studies. The goal of these studies was to evaluate the effects of oral exposure to 1-20ml of artificially weathered Mississippi Canyon 252 oil kg bw -1 day -1 from one to 28 days or one to five applications of oil to 20% of the bird's surface area. It was thought that these exposure levels would not result in immediate or short-term mortality but might result in physiological effects that ultimately could affect avian survival, reproduction and health. These studies included oral dosing studies, an external dosing study, metabolic and flight performance studies and field-based flight studies. Results of these studies indicated changes in hematologic endpoints including formation of Heinz bodies and changes in cell counts. There were also effects on multiple organ systems, cardiac function and oxidative status. External oiling affected flight patterns and time spent during flight tasks indicating that migration may be affected by short-term repeated exposure to oil. Feather damage also resulted in increased heat loss and energetic demands. The papers in this special issue indicate that the combined effects of oil toxicity and feather effects in avian species, even in the case of relatively light oiling, can significantly affect the overall health of birds., (Copyright © 2017. Published by Elsevier Inc.)

The Oil Pollution Act of 1990 establishes liability for injuries to natural resources because of the release or threat of release of oil. Assessment of injury to natural resources resulting from an oil spill and development and implementation of a plan for the restoration, rehabilitation, replacement or acquisition of natural resources to compensate for those injuries is accomplished through the Natural Resource Damage Assessment (NRDA) process. The NRDA process began within a week of the Deepwater Horizon oil spill, which occurred on April 20, 2010. During the spill, more than 8500 dead and impaired birds representing at least 93 avian species were collected. In addition, there were more than 3500 birds observed to be visibly oiled. While information in the literature at the time helped to identify some of the effects of oil on birds, it was not sufficient to fully characterize the nature and extent of the injuries to the thousands of live oiled birds, or to quantify those injuries in terms of effects on bird viability. As a result, the US Fish and Wildlife Service proposed various assessment activities to inform NRDA injury determination and quantification analyses associated with the Deepwater Horizon oil spill, including avian toxicity studies. The goal of these studies was to evaluate the effects of oral exposure to 1-20ml of artificially weathered Mississippi Canyon 252 oil kg bw -1 day -1 from one to 28 days or one to five applications of oil to 20% of the bird's surface area. It was thought that these exposure levels would not result in immediate or short-term mortality but might result in physiological effects that ultimately could affect avian survival, reproduction and health. These studies included oral dosing studies, an external dosing study, metabolic and flight performance studies and field-based flight studies. Results of these studies indicated changes in hematologic endpoints including formation of Heinz bodies and changes in cell counts. There were also effects on multiple organ systems, cardiac function and oxidative status. External oiling affected flight patterns and time spent during flight tasks indicating that migration may be affected by short-term repeated exposure to oil. Feather damage also resulted in increased heat loss and energetic demands. The papers in this special issue indicate that the combined effects of oil toxicity and feather effects in avian species, even in the case of relatively light oiling, can significantly affect the overall health of birds., (Copyright © 2017 Elsevier Inc. All rights reserved.)

A lateral flow immunoassay (LFIA) has been developed and fully validated to detect the primary amnesic shellfish poisoning (ASP) toxin, domoic acid (DA). The performance characteristics of two versions of the test were investigated using spiked and naturally contaminated shellfish (mussels, scallops, oysters, clams, and cockles). The tests provide a qualitative result, to indicate the absence or presence of DA in extracts of shellfish tissues, at concentrations that are relevant to regulatory limits. The new rapid assay (LFIA version 2) was designed to overcome the performance limitations identified in the first version of the assay. The improved test uses an electronic reader to remove the subjective nature of the generated results, and the positive cut-off for screening of DA in shellfish was increased from 10 ppm (version 1) to 17.5 ppm (version 2). A simple extraction and test procedure was employed, which required minimal equipment and materials; results were available 15 min after sample preparation. Stability of the aqueous extracts at room temperature (22 °C) at four time points (up to 245 min after extraction) and across a range of DA concentrations was 100.3±1.3% and 98.8±2.4% for pre- and post-buffered extracts, respectively. The assay can be used both within laboratory settings and in remote locations. The accuracy of the new assay, to indicate negative results at or below 10 ppm DA, and positive results at or above 17.5 ppm, was 99.5% (n=216 tests). Validation data were obtained from a 2-day, randomised, blind study consisting of multiple LFIA lots (n=3), readers (n=3) and operators (n=3), carrying out multiple extractions of mussel tissue (n=3) at each concentration (0, 10, 17.5, and 20 ppm). No matrix effects were observed on the performance of the assay with different species (mussels, scallops, oysters, clams, and cockles). There was no impact on accuracy or interference from other phycotoxins, glutamic acid or glutamine with various strip incubations (8, 10, and 12 min). The accuracy of the assay, using naturally contaminated samples to indicate negative results at or below 12.5 ppm and positive results at or above 17.5 ppm, was 100%. Variability between three LFIA lots across a range of DA concentrations, expressed as coefficient of variation (% CV), was 1.1±0.4% (n=2 days) based on quantitative readings from the electronic reader. During an 8 week stability study, accuracy of the method with test strips stored at various temperatures (6, 22, 37 and 50 °C) was 100%. Validation for both versions included comparisons with results obtained using reference LC-UV methods., (© 2013 Elsevier B.V. All rights reserved.)

Persons at risk for autosomal dominant neurodegenerative diseases provide the opportunity to efficiently test preventive interventions. Only a minority of such persons, however, choose to undergo revealing genetic testing, presenting a challenge to enrollment. Thirty-four preclinical Latinos (n = 26) and non-Latinos at risk for familial Alzheimer's disease (FAD) unaware of their genetic status were administered a questionnaire exploring their interest in undergoing revealing genetic testing at baseline and in the context of eligibility for four prevention trials of increasing invasiveness. Forty-four percent of subjects expressed a baseline interest in undergoing revealing testing which increased to 85% in order to be eligible for a study of an oral drug "felt to be very safe." If there were a 50% chance of receiving placebo, this number dropped to 62% (p = 0.02). Among those not interested in a study involving a 50% chance of receiving placebo, a range of 5% to 40% chance of receiving placebo was given as acceptable. For more invasive studies, living in the United States (as opposed to Mexico) positively influenced the likelihood of participating. Our data suggest that clinical trial designs in which persons must confront their genetic status prior to enrollment are feasible. Study designs to minimize the likelihood of being placed on placebo or provide the eventual administration of the drug through open-label extensions should be considered., (© 2013. Published by Elsevier Inc. All rights reserved.)

Mercury and PCBs are used by non-governmental organizations and federal agencies to inform seafood safety recommendations. Pollution dynamics suggest recommendations on the national scale may be too large to be accurate. We tested softshell and hardshell blue crab, white and pink shrimp, oysters, clams, spot, and mullet from fishers in each of the three North Carolina fishery districts. We measured mercury using EPA method 7473 and PCBs using a commercially available ELISA kit. Over 97% of samples were below the Environmental Protection Agency levels of concern for both mercury and PCBs. Mercury and PCBs have different spatial dynamics, but both differ significantly by water body, suggesting that seafood safety recommendations should occur by water body instead of at the national scale. This finding supports previous research suggesting that differences in water chemistry, terrestrial influence, and flushing time in a particular water body control the contaminant load in locally resident species., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Mutations in the WT1 gene are found in a subset of Wilms' tumours and in certain other disorders such as Denys-Drash syndrome. The WT1 gene product is a zinc finger transcription factor for which many target genes have been suggested. Here we utilise gene targeting to generate cells containing only truncated forms of WT1, in which the DNA-binding region is disrupted. Examination of gene expression in these cells using cDNA macroarrays suggests two novel WT1 transcriptional targets, cyclin G1 (Ccng1), and insulin-like growth factor binding protein 4 (Igfbp4)., (Copyright 2001 Academic Press.)

The results from the measurement of the fluorescence spectra of fluoroquinolone antibiotics including ofloxacin (OF), norfloxacin (NOR) and ciprofloxacin (CIP) complexed with cobalt (II) and ATP give information concerning the antibiotics-nucleotide interactions. From the fluorescence spectral data, it appears that the fluoroquinolone antibiotic cannot directly complex with ATP but indirectly complex with cobalt (II), which is playing an intermediary role. The interaction of fluoroquinolone antibiotic with the nucleotide occurs mainly through the phosphate group. The conclusion offers a more complete mechanism, which is important for understanding the interaction of these drugs with DNA.

A simple method has been developed for the quantitative determination of ephedrine in ephedra callus. The dependence of effective mobility of ephedrine on pH was investigated, and a simulated equation was obtained. The separation was performed in an uncoated capillary and detected at 185 nm. A new Tris-NaOH-H(3)PO(4) run buffer was used and the pH was adjusted to 3.20. To increase the solubility of hydrophobic analytes and improve the separation efficiency, 15% acetonitrile was used in the buffer as a modifier. The content of ephedrine in an ephedra callus sample and an ephedra herba sample were determined with this method, and the result was satisfactory.

A growing body of evidence indicates that young animals exhibit an increased susceptibility to the lethal effects of cholinesterase (ChE)-inhibiting insecticides. Our laboratory is engaged in defining factors which may explain this age-related sensitivity. This report includes results from experiments designed to compare the developmental profiles, kinetic parameters and intrinsic (i.e. in vitro) sensitivity of developing male rat brain acetylcholinesterase (AChE) activity to carbamate and organophosphorus anticholinesterases. Total ChE activity in whole brain for each age was composed of about 90% AChE and 10% butyrylcholinesterase (BuChE) activity for the six ages examined. Brain AChE activity showed an age-related increase in Vmax until postnatal day 17 with no change in Km (average of all six ages approximately equal to 72 microM). Optimal substrate (acetylthiocholine) concentration for each age was 1 mM, and there was substrate inhibition (approximately 10%) at 2.5 mM. IC50s (the concentration of compound that inhibits 50% of the AChE activity in 30 min at 26 degrees C) defined concomitantly for postnatal day 4 and adult brain AChE using either aldicarb, carbaryl, chlorpyrifos-oxon or malaoxon were virtually identical at both ages with average IC50 values being: aldicarb = 2.4 microM, carbaryl = 1.7 microM, chlorpyrifos-oxon = 4.9 nM and malaoxon = 140 nM. In summary, AChE in young and adult brain differs mostly in specific activity while the Km(s), substrate profiles, and in vitro sensitivity to selected anticholinesterase insecticides are not different. Therefore, these data support the hypothesis that the greater sensitivity of the young animals to anticholinesterase pesticides is not due to the greater sensitivity of the target molecule AChE to these inhibitors.

The mouse Pim-1 gene encodes two cytoplasmic serine-threonine-specific protein kinases. The gene has been found to be activated (overexpressed) by retroviral insertion in hematopoietic tumors in mice. Transgenic mice that overexpress Pim-1 (E mu-Pim-1) have a low incidence of spontaneous T-cell lymphomas and an increased susceptibility to Moloney murine leukemia virus and N-ethyl-N-nitrosourea-induced lymphomas. Apart from a slight enlargement of the spleen, no abnormalities were found in prelymphomatous transgenic mice. Inactivation of the Pim-1 gene in the germline of mice resulted in mice with a surprisingly subtle phenotype. Therefore, we investigated whether subtle effects of the absence of Pim-1 could be made visible during in vitro culturing of hematopoietic cells. We found that bone marrow-derived mast cells (BMMC) lacking Pim-1 had a distinct growth disadvantage when grown on interleukin (IL)-3, but not when stimulated by the factors IL-4, IL-9, or Steel factor (SF). This indicates a role for Pim-1 as a modulator of the IL-3 signal transduction pathway.

Two biochemical assays were developed which promote and measure the induced reactivation of carbamate-inhibited cholinesterases in avian and mammalian brain and plasma samples. The effects of inhibitor concentration, temperature, and the extent of dilution on the achievement of a steady state equilibrium and the subsequent level and rate of recovery of brain cholinesterase activity were investigated. A similar procedure for reactivation of carbamate-inhibited plasma cholinesterase activity involved the removal of excess carbamate from a small sample volume (< 400 microliters). Both methods begin by measuring cholinesterase activity immediately following dilution and involve an incubation period during which conditions for spontaneous reactivation of the inhibited enzymes are maximized. Both assays are suitable for large-scale, rapid use and appear able to restore inhibited cholinesterase activity to levels closely approximating that of control values for each species tested. These methods will not only maximize the usefulness of cholinesterases in monitoring carbamate pesticide exposure but should prove to be extremely useful tools in the forensic assessment of carbamate exposure in human and wildlife pesticide incidents.

To assess tolerance to cocaine in a self-administration paradigm, rats were trained to self-administer cocaine (0.25 mg/injection) on a fixed-ratio 2 (FR2) schedule of reinforcement. The development of tolerance was studied during chronic administration of cocaine (20 mg/kg per 8 h for 10 days), given either contingently (self-administered by the rats) or non-contingently (infused by the experimenter). Both contingent and non-contingent administration of cocaine produced comparable tolerance, as indicated by a faster rate of cocaine self-administration (the average inter-reinforcer time, ISRT, decreased significantly). Tolerance developed by day 2 of the chronic regimen and reached a floor value (60% of baseline) from day 4 through day 10. Termination of chronic cocaine then resulted in recovery from tolerance, with ISRTs returning to baseline within 6 days of termination. A second set of experiments determined whether tolerance could be studied using a multi-dose method to obtain dose-response data in a single session. A system of multiple pumps allowed testing of three doses of cocaine during a single experimental session. Cocaine dose-response curves obtained from the multi-dose method: (i) did not differ from that obtained from a single-dose method; (ii) were reproducible; and (iii) were shifted to the right by Schering 23390. Rats were then subjected to a 7-day chronic regimen of infused cocaine (20 mg/kg per 8 h) or infused saline. At the end of this chronic cocaine period, they were tested with the multi-dose method. Chronic cocaine, as compared to chronic saline, shifted the cocaine dose-response curve to the right, indicating that the multi-dose method can be successfully applied to demonstrate tolerance to the effects of cocaine in a self-administration paradigm.

Ondansetron (GR38032F), a serotonin 5HT3 antagonist, is active in numerous behavioral paradigms and neurochemical systems. Since 5HT3 antagonists have been suggested as therapeutic agents for the treatment of drug abuse, the action of ondansetron on cocaine drug discrimination and self-administration paradigms in rats was investigated. Doses of ondansetron (0.001 - 1.0 mg/kg) had no effect on the discriminative stimulus properties of 10 mg/kg cocaine. In contrast SCH23390, a dopamine D1 antagonist known to block cocaine discrimination, acted as previously reported. Ondansetron did not augment the effects of SCH23390, but at higher doses, combinations of ondansetron and SCH23390 produced disruption of lever pressing in the presence of cocaine. Ondansetron (0.001-1.0 mg/kg) had no effect on the self-administration of various doses of cocaine, nor did it have any effect on reacquisition of cocaine self-administration in animals with a history of active administration followed by a period of abstinence. As before, SCH23390, known to block cocaine self-administration, acted as previously reported. Although other 5HT antagonists may prove to be efficacious in cocaine abuse, ondansetron appears unlikely to alter the subjective or rewarding stimulus properties of cocaine.

Inbred normal and genetically dystrophic chickens of New Hampshire and White Leghorn backgrounds, respectively, have been crossed to yield hybrids of normal and dystrophic genotypes in order to provide genetically homogeneous but heterozygous experimental animals. This study examined carcass and pectoral muscle weights, pectoral muscle fiber diameters, serum creatine kinase (CK) levels, muscle acetylcholinesterase (AChE), lactic dehydrogenase (LDH), and creatine kinase, and response to daily injections of corticosterone-21-acetate (C21A) of these hybrid chickens and their inbred parental lines. With the exception of pectoral muscle weight, dystrophic hybrids exhibited symptoms of dystrophy: high serum CK and high muscle AChE and low LDH levels. The results support the hypothesis that neither early muscle fiber hypertrophy nor atrophy is invariably associated with expression of the dystrophic gene; both are the result of secondary gene interactions. One experiment showed that muscle AChE levels decreased and LDH levels rose after C21A treatments.

Many pluripotent embryonal carcinoma (EC) cell lines and all embryonic stem (ES) cell lines have hitherto been maintained in the undifferentiated state only by culture on feeder layers of mitomycin C-treated embryonic fibroblasts. We now demonstrate that medium conditioned by incubation with Buffalo rat liver (BRL) cells prevents the spontaneous differentiation of such cells which occurs when they are plated in the absence of feeders. This effect is not mediated via cell selection but represents a fully reversible inhibitory action ascribed to a differentiation-inhibiting activity (DIA). BRL-conditioned medium can therefore replace feeders in the propagation of homogeneous stem cell populations. Such medium also restricts differentiation in embryoid bodies formed via aggregation of EC cells and partially inhibits retinoic acid-induced differentiation. The PSA4 EC line gives rise only to extraembryonic endoderm-like cells when aggregated or exposed to retinoic acid in BRL-conditioned medium. This suggests that DIA may be lineage-specific. DIA is a dialysable, acid-stable entity of apparent molecular weight 20,000-35,000. Its actions are reproduced neither by insulin-like growth factor-II nor by transforming growth factor-beta. DIA thus appears to be a novel factor exerting a negative control over embryonic stem cell differentiation.