313 research outputs found
Toxicity Evaluation of a Novel Magnetic Resonance Imaging Marker CoCl2-N-Acetylcysteine in Rats
C4 (cobalt dichloride-N-acetylcysteine [1% CoCl 2 :2% NAC]) is a novel magnetic resonance imaging contrast marker that facilitates visualization of implanted radioactive seeds in cancer brachytherapy. We evaluated the toxicity of C4. Rats were assigned to control (0% CoCl 2 :NAC), low-dose (0.1% CoCl 2 :2% NAC), reference-dose (C4), and high-dose (10% CoCl 2 :2% NAC) groups. Agent was injected into the left quadriceps femoris muscle of the rats. Endpoints were organ and body weights, hematology, and serum chemistry and histopathologic changes of tissues at 48 hours and 28 and 63 days after dosing. Student\u27s t tests were used. No abnormalities in clinical signs, terminal body and organ weights, or hematologic and serum chemistry were noted, and no gross or histopathologic lesions of systemic tissue toxicity were found in any treatment group at any time point studied. At the site of injection, concentration-dependent acute responses were observed in all treatment groups at 48 hours after dosing and were recovered by 28 days. No myofiber degeneration or necrosis was observed at 28 or 63 days in any group. In conclusion, a single intramuscular dose of C4 produced no acute or chronic systemic toxicity or inflammation in rats, suggesting that C4 may be toxicologically safe for clinical use in cancer brachytherapy
Progress in Interferometry for LISA at JPL
Recent advances at JPL in experimentation and design for LISA interferometry
include the demonstration of Time Delay Interferometry using electronically
separated end stations, a new arm-locking design with improved gain and
stability, and progress in flight readiness of digital and analog electronics
for phase measurements.Comment: 11 pages, 9 figures, LISA 8 Symposium, Stanford University, 201
Exercise counselling and referral in cancer care: An international scoping survey of health care practitioners’ knowledge, practices, barriers, and facilitators
Purpose:
Evidence supports the role of prescribed exercise for cancer survivors, yet few are advised to exercise by a healthcare practitioner (HCP). We sought to investigate the gap between HCPs’ knowledge and practice from an international perspective.
Methods:
An online questionnaire was administered to HCPs working in cancer care between February 2020 and February 2021. The questionnaire assessed knowledge, beliefs, and practices regarding exercise counselling and referral of cancer survivors to exercise programs.
Results:
The questionnaire was completed by 375 participants classified as medical practitioners (42 %), nurses (28 %), exercise specialists (14 %), and non-exercise allied health practitioners (16 %). Between 35 and 50 % of participants self-reported poor knowledge of when, how, and which cancer survivors to refer to exercise programs or professionals, and how to counsel based on exercise guidelines. Commonly reported barriers to exercise counselling were safety concerns, time constraints, cancer survivors being told to rest by friends and family, and not knowing how to screen people for suitability to exercise (40 – 48 %). Multivariable logistic regression models including age, gender, practitioner group, leisure-time physical activity, and recall of guidelines found significant effects for providing specific exercise advice (χ2(7) = 117.31, p \u3c .001), discussing the role of exercise in symptom management (χ2(7) = 65.13, p \u3c .001) and cancer outcomes (χ2(7) = 58.69, p \u3c .001), and referring cancer survivors to an exercise program or specialist (χ2(7) = 72.76, p \u3c .001). Conclusion: Additional education and practical support are needed to equip HCPs to provide cancer survivors with exercise guidelines, resources, and referrals to exercise specialists
Telaprevir twice daily is noninferior to telaprevir every 8 hours for patients with chronic hepatitis C.
Background & Aims We performed an open-label, multicenter, phase 3 study of the safety and efficacy of twice-daily telaprevir in treatment-naive patients with chronic hepatitis C virus (HCV) genotype 1 infection, including those with cirrhosis. Methods Patients were randomly assigned to groups treated with telaprevir 1125 mg twice daily or 750 mg every 8 hours plus peginterferon alfa-2a and ribavirin for 12 weeks; patients were then treated with peginterferon alfa-2a and ribavirin alone for 12 weeks if their level of HCV RNA at week 4 was <25 IU/mL or for 36 weeks if their level was higher. The primary objective was to demonstrate noninferiority of telaprevir twice daily versus every 8 hours in producing a sustained virological response 12 weeks after the end of therapy (SVR12) (based on a -11% lower limit of the 95% lower confidence interval for the difference between groups). Results At baseline, of 740 patients, 85% had levels of HCV RNA ≥800,000 IU/mL, 28% had fibrosis (F3-F4), 14% had cirrhosis (F4), 57% were infected with HCV genotype 1a, and 71% had the non-CC IL28B genotype. Of patients who were treated with telaprevir twice daily, 74.3% achieved SVR12 compared with 72.8% of patients who were treated with telaprevir every 8 hours (difference in response, 1.5%; 95% confidence interval, -4.9% to 12.0%), so telaprevir twice daily is noninferior to telaprevir every 8 hours. All subgroups of patients who were treated with telaprevir twice daily versus those who were treated every 8 hours had similar rates of SVR12. The most frequent adverse events (AEs) in the telaprevir phase were fatigue (47%), pruritus (43%), anemia (42%), nausea (37%), rash (35%), and headache (26%); serious AEs were reported in 9% of patients. Rates of AEs and serious AEs were similar or slightly higher among patients treated with telaprevir every 8 hours. Conclusions Based on a phase 3 trial, telaprevir twice daily is noninferior to every 8 hours in producing SVR12, with similar levels of safety and tolerability. These results support use of telaprevir twice daily in patients with chronic HCV genotype 1 infection, including those with cirrhosis. ClinicalTrials.gov, Number: NCT0124176
Lymphatic Mapping and Sentinel Lymph Node Biopsy for Patients With Local Recurrence After Breast-Conservation Therapy
Local recurrence (LR) after breast-conservation therapy for breast cancer occurs in 10% to 15% of cases. A subset of these represents biologically aggressive disease, yet prognostic features for identifying this high-risk category are lacking. We hypothesized that lymphatic mapping and sentinel lymph node biopsy would provide useful information regarding dominant lymphatic drainage patterns of patients with LR.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41410/1/10434_2006_Article_9252.pd
The role of triplet states in the long wavelength absorption region of bromine nitrate
A theoretical study of the low-lying singlet and triplet electronic states of BrONO 2 is presented. Calculations of excitation energies and oscillator strengths are reported using excited-state coupled cluster response methods, as well as the complete active space self-consistent field method with the full Breit-Pauli spin-orbit operator. The calculations predict that there is only one singlet state for BrONO 2 , the à 1 AЉ state, that is accessible at wavelengths longer than 300 nm. At energies below the first singlet state, i.e., Ͼ330 nm, the calculations reveal two triplet states with significant oscillator strength. Therefore, we propose that the origin of absorption in the long wavelength region from 350 to 500 nm, responsible for the majority of atmospheric photolysis, is due to transitions to triplet states and not singlet states. A comparison of the reported benchmark coupled cluster calculations ͑CCSD͒ with the results of ͑1͒ configuration interaction with all single substitutions and a perturbative correction for the double substitutions ͓CIS͑D͔͒ and ͑2͒ time-dependent density-functional ͑TDDF͒ calculations is provided. For the lowest energy excitations, CIS͑D͒ calculations provide quantitative agreement with the CCSD results, while TDDF calculations yield qualitative agreement
2-Pyrrolidinone and Succinimide as Clinical Screening Biomarkers for GABA-Transaminase Deficiency: Anti-seizure Medications Impact Accurate Diagnosis
Broad-scale untargeted biochemical phenotyping is a technology that supplements widely accepted assays, such as organic acid, amino acid, and acylcarnitine analyses typically utilized for the diagnosis of inborn errors of metabolism. In this study, we investigate the analyte changes associated with 4-aminobutyrate aminotransferase (ABAT, GABA transaminase) deficiency and treatments that affect GABA metabolism. GABA-transaminase deficiency is a rare neurodevelopmental and neurometabolic disorder caused by mutations in ABAT and resulting in accumulation of GABA in the cerebrospinal fluid (CSF). For that reason, measurement of GABA in CSF is currently the primary approach to diagnosis. GABA-transaminase deficiency results in severe developmental delay with intellectual disability, seizures, and movement disorder, and is often associated with death in childhood. Using an untargeted metabolomics platform, we analyzed EDTA plasma, urine, and CSF specimens from four individuals with GABA-transaminase deficiency to identify biomarkers by comparing the biochemical profile of individual patient samples to a pediatric-centric population cohort. Metabolomic analyses of over 1,000 clinical plasma samples revealed a rich source of biochemical information. Three out of four patients showed significantly elevated levels of the molecule 2-pyrrolidinone (Z-score ≥ 2) in plasma, and whole exome sequencing revealed variants of uncertain significance in ABAT. Additionally, these same patients also had elevated levels of succinimide or its ring-opened form, succinamic acid, in plasma, urine, and CSF and/or homocarnosine in urine and CSF. In the analysis of clinical EDTA plasma samples, the levels of succinamic acid and 2-pyrrolidinone showed a high level of correlation (R = 0.72), indicating impairment in GABA metabolism and further supporting the association with GABA-transaminase deficiency and the pathogenicity of the ABAT variants. Further analysis of metabolomic data across our patient population revealed the association of elevated levels of 2-pyrrolidinone with administration of vigabatrin, a commonly used anti-seizure medication and a known inhibitor of GABA-transaminase. These data indicate that anti-seizure medications may alter the biochemical and metabolomic data, potentially impacting the interpretation and diagnosis for the patient. Further, these data demonstrate the power of combining broad scale genotyping and phenotyping technologies to diagnose inherited neurometabolic disorders and support the use of metabolic phenotyping of plasma to screen for GABA-transaminase deficiency
Statistical practices of educational researchers: An analysis of their ANOVA, MANOVA, and ANCOVA analyses
Articles published in several prominent educational journals were examined to investigate the use of data-analysis tools by researchers in four research paradigms: between-subjects univariate designs, between-subjects multivariate designs, repeated measures designs, and covariance designs. In addition to examining specific details pertaining to the research design (e.g., sample size, group size equality/inequality) and methods employed for data analysis, we also catalogued whether: (a) validity assumptions were examined, (b) effect size indices were reported, (c) sample sizes were selected based on power considerations, and (d) appropriate textbooks and/or articles were cited to communicate the nature of the analyses that were performed. Our analyses imply that researchers rarely verify that validity assumptions are satisfied and accordingly typically use analyses that are nonrobust to assumption violations. In addition, researchers rarely report effect size statistics, nor do they routinely perform power analyses to determine sample size requirements. We offer many recommendations to rectify these shortcomings.Social Sciences and Humanities Research Counci
Nipple aspiration and ductal lavage in women with a germline BRCA1 or BRCA2 mutation
INTRODUCTION: The aim of this study was to collect serial samples of nipple aspirate (NA) and ductal lavage (DL) fluid from women with germline BRCA1/2 mutations in order to create a biorepository for use in identifying biomarkers of breast cancer risk. METHODS: Between March 2003 and February 2005, 52 women with germline BRCA1 or BRCA2 mutations (median age 43 years, range 27 to 65 years) were scheduled for six-monthly NA, DL and venesection. DL was attempted for all NA fluid-yielding (FY) and any non-FY ducts that could be located at each visit. RESULTS: Twenty-seven (52%) women were postmenopausal, predominantly (19/27) from risk reducing bilateral salpingo-oophorectomy (BSO). FY ducts were identified in 60% of all women, 76% of premenopausal women versus 44% of postmenopausal (P = 0.026). Eighty-five percent of women had successful DL. Success was most likely in women with FY ducts (FY 94% versus non-FY 71% (P = 0.049). DL samples were more likely to be cellular if collected from FY ducts (FY 68% versus non-FY 43%; P = 0.037). Total cell counts were associated with FY status (FY median cell count 30,996, range 0 to >1,000,000 versus non-FY median cell count 0, range 0 to 173,577; P = 0.002). Four women (8%) had ducts with severe atypia with or without additional ducts with mild epithelial atypia; seven others had ducts with mild atypia alone (11/52 (21%) in total). Median total cell count was greater from ducts with atypia (105,870, range 1920 to >1,000,000) than those with no atypia (174, 0 to >1,000,000; P ≤ 0.001). CONCLUSION: It is feasible to collect serial NA and DL samples from women at high genetic risk of breast cancer, and we are creating a unique, prospective collection of ductal samples that have the potential to be used for discovery of biomarkers of breast cancer risk and evaluate the ongoing effects of risk reducing BSO. DL cellular atypia was not predictive of a current breast cancer and longer follow up is needed to determine whether atypia is an additional marker of future breast cancer risk in this population already at high genetic risk of breast cancer
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