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Abstract
The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater's sedimentary delta, finding the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich rock, which accumulated at the base of a magma body. Fe-Mg carbonates along grain boundaries indicate reactions with CO2-rich water, under water-poor conditions. Overlying Séítah is a unit informally named Máaz, which we interpret as lava flows or the chemical complement to Séítah in a layered igneous body. Voids in these rocks contain sulfates and perchlorates, likely introduced by later near-surface brine evaporation. Core samples of these rocks were stored aboard Perseverance for potential return to Earth.
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Abstract
The geological units on the floor of Jezero crater, Mars, are part of a wider regional stratigraphy of olivine-rich rocks, which extends well beyond the crater. We investigate the petrology of olivine and carbonate-bearing rocks of the Séítah formation in the floor of Jezero. Using multispectral images and x-ray fluorescence data, acquired by the Perseverance rover, we performed a petrographic analysis of the Bastide and Brac outcrops within this unit. We find that these outcrops are composed of igneous rock, moderately altered by aqueous fluid. The igneous rocks are mainly made of coarse-grained olivine, similar to some Martian meteorites. We interpret them as an olivine cumulate, formed by settling and enrichment of olivine through multi-stage cooling of a thick magma body.
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Effects and moderators of exercise on sleep in adults with cancer: Individual patient data and aggregated meta-analyses. J Psychosom Res 2019; 124:109746. [PMID: 31443811 DOI: 10.1016/j.jpsychores.2019.109746] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 06/14/2019] [Accepted: 06/16/2019] [Indexed: 12/15/2022]
Abstract
OBJECTIVES To evaluate the effects of exercise interventions on sleep disturbances and sleep quality in patients with mixed cancer diagnoses, and identify demographic, clinical, and intervention-related moderators of these effects. METHODS Individual patient data (IPD) and aggregated meta-analyses of randomized controlled trials (RCTs). Using data from the Predicting OptimaL cAncer RehabIlitation and Supportive care project, IPD of 2173 adults (mean age = 54.8) with cancer from 17 RCTs were analyzed. A complementary systematic search was conducted (until November 2018) to study the overall effects and test the representativeness of analyzed IPD. Effect sizes of exercise effects on self-reported sleep outcomes were calculated for all included RCTs. Linear mixed-effect models were used to evaluate the effects of exercise on post-intervention outcome values, adjusting for baseline values. Moderator effects were studied by testing interactions for demographic, clinical and intervention-related characteristics. RESULTS For all 27 eligible RCTs from the updated search, exercise interventions significantly decreased sleep disturbances in adults with cancer (g = -0.09, 95% CI [-0.16; -0.02]). No significant effect was obtained for sleep quality. RCTs included in IPD analyses constituted a representative sample of the published literature. The intervention effects on sleep disturbances were not significantly moderated by any demographic, clinical, or intervention-related factor, nor by sleep disturbances. CONCLUSIONS This meta-analysis provides some evidence that, compared to control conditions, exercise interventions may improve sleep disturbances, but not sleep quality, in cancer patients, although this effect is of a small magnitude. Among the investigated variables, none was found to significantly moderate the effect of exercise interventions on sleep disturbances.
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Validation of inflammatory genetic variants associated with long-term cancer related fatigue in a large breast cancer cohort. Brain Behav Immun 2018; 73:252-260. [PMID: 29763737 DOI: 10.1016/j.bbi.2018.05.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 05/02/2018] [Accepted: 05/09/2018] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Studies to date have reported several associations between single nucleotide polymorphisms (SNPs) and cancer related fatigue (CRF), but have been limited by small sample sizes, missing adjustment for relevant covariates or multiple testing, as well as varying CRF definitions, i.e. time and method of assessment. This study aimed to validate previously reported associations using the largest independent breast cancer sample to date and to evaluate further functional cytokine variants in relation to total CRF and all relevant CRF subdomains (physical, cognitive, and affective CRF). METHOD 45 candidate SNPs in inflammatory pathway genes were selected based on previous reports (16 SNPs) or regulatory function (29 SNPs). Breast cancer patients recruited between 2002 and 2005 provided information on CRF at first follow-up (FU1) (N = 1389) and second follow-up (FU2) (N = 950), a median of 6.2 years and 11.7 years respectively after diagnosis. SNP associations were assessed using linear regression models on CRF scores separately for FU1 and FU2. Additionally, patients with persistent fatigue (fatigued at both time-points) were compared to those never fatigued using logistic regression models (N = 684). All analyses were adjusted for relevant covariates. Secondary analyses were conducted for CRF subdomains. RESULTS For total CRF none of the previously reported associations were confirmed after correction for multiple testing. The p-value distribution of all SNPs was not different than the one expected by chance. Analyses of CRF subdomains yielded a significant association between TNF-α rs3093662 and persistent physical CRF (Odds Ratio (OR) = 3.23, 95% Confidence Interval (CI) = 1.71-6.10, p = 0.0003). CONCLUSION We were unable to confirm previously reported findings, suggesting that individual SNPs are unlikely to be of clinical utility. Further investigations in well powered studies are warranted, which consider genetic heterogeneity according to subdomains of CRF.
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Abstract
Summary
Objectives:
Questionnaires used in epidemiological studies should be validated. However, unclarity exists about the appropriate statistical methods and interpretation of validation studies. Thus, we investigated the theory and practice of statistical evaluation approaches.
Methods:
Using three platforms, a literature review, own simulations, and a validation study performed by ourselves, we worked out relevant limitations, advantages, and new important aspects of evaluation methods.
Results:
Our systematic literature review, based on physical activity questionnaires, revealed that correlation coefficients are still the common approach in validation studies, found in 41 of 46 reviewed publications (89.1%). This practice has been criticized in the theoretically oriented literature for more than 20 years. Appropriate evaluation methods as recommended by Bland and Altman were found in only ten publications (21.7 %).We showed that serious bias in questionnaires can be revealed by Bland-Altman plots but may remain undetected by correlation coefficients. With our simulations we refuted the argument that correlation coefficients properly investigate whether a questionnaire ranks the subjects sufficiently well. Further, with Bland-Altman analyses we could evaluate differential errors with respect to case-control status in our validation study. Yet, this was not possible with correlation coefficients, because they generally do not identify systematic bias. In addition, we show a potential pitfall in the interpretation of Bland-Altman plots that might occur in specific rare instances.
Conclusions:
The commonly used correlation approach can yield misleading conclusions in validation studies. A more frequent and proper use of the Bland-Altman methods would be desirable to improve epidemiological data quality.
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Abstract
Summary
Objectives: Epidemiological evidence suggests an inverse association between physical activity (PA) and postmenopausal breast cancer risk. Breast cancer is a heterogeneous disease, influenced by reproductive factors, lifestyle pattern, and predispositions. We investigated whether these risk factors modify the effect of PA on breast cancer risk.
Methods: We analyzed data from 2004 hormone-receptor-positive postmenopausal breast cancer cases and 6569 controls from the population-based MARIE study conducted 2002–2005 in Germany. Interaction was statistically tested using adjusted unconditional logistic regression models.
Results: The inverse association between leisure-time PA and risk of postmenopausal hormone-receptor-positive breast cancer was not heterogeneous by family history of breast cancer or by hormone therapy. PA showed a significant interaction with benign breast diseases (p = 0.023) and with breastfeeding (p = 0.045) but not with parity (p = 0.94), with clear risk reductions only for women who ever had breastfed or who ever had a benign breast disease (among ever breastfed: odds ratio = 0.63; 95% confidence interval = (0.52, 0.77), highest vs. lowest PA quartile). Interaction with BMI was weak (p = 0.053).
Conclusions: Breastfeeding and benign breast diseases modified the effect of PA on postmenopausal breast cancer risk. If other studies find similar modifications, increasing knowledge about these risk factors may contribute to a better understanding of the mode of action of PA on breast cancer risk. For women who are at higher risk for breast cancer due to family history or due to hormone therapy use, it is encouraging that they might lower their risk by being physically active.
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Schlafprobleme von Brustkrebspatientinnen unter adjuvanter Therapie: Determinanten und Effekte von körperlichem Training. DAS GESUNDHEITSWESEN 2017. [DOI: 10.1055/s-0037-1605841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Redox stratification of an ancient lake in Gale crater, Mars. Science 2017; 356:356/6341/eaah6849. [PMID: 28572336 DOI: 10.1126/science.aah6849] [Citation(s) in RCA: 171] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Accepted: 04/19/2017] [Indexed: 11/02/2022]
Abstract
In 2012, NASA's Curiosity rover landed on Mars to assess its potential as a habitat for past life and investigate the paleoclimate record preserved by sedimentary rocks inside the ~150-kilometer-diameter Gale impact crater. Geological reconstructions from Curiosity rover data have revealed an ancient, habitable lake environment fed by rivers draining into the crater. We synthesize geochemical and mineralogical data from lake-bed mudstones collected during the first 1300 martian solar days of rover operations in Gale. We present evidence for lake redox stratification, established by depth-dependent variations in atmospheric oxidant and dissolved-solute concentrations. Paleoclimate proxy data indicate that a transition from colder to warmer climate conditions is preserved in the stratigraphy. Finally, a late phase of geochemical modification by saline fluids is recognized.
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Effects of 12-week resistance training during radiotherapy in breast cancer patients. Scand J Med Sci Sports 2016; 27:1500-1510. [DOI: 10.1111/sms.12777] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/23/2016] [Indexed: 01/21/2023]
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Physiologic and Molecular Mechanisms Linking Endurance and Resistance Training with Effects for Cancer Patients. DEUTSCHE ZEITSCHRIFT FÜR SPORTMEDIZIN 2014. [DOI: 10.5960/dzsm.2014.136] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Abstract
Sedimentary rocks examined by the Curiosity rover at Yellowknife Bay, Mars, were derived from sources that evolved from an approximately average martian crustal composition to one influenced by alkaline basalts. No evidence of chemical weathering is preserved, indicating arid, possibly cold, paleoclimates and rapid erosion and deposition. The absence of predicted geochemical variations indicates that magnetite and phyllosilicates formed by diagenesis under low-temperature, circumneutral pH, rock-dominated aqueous conditions. Analyses of diagenetic features (including concretions, raised ridges, and fractures) at high spatial resolution indicate that they are composed of iron- and halogen-rich components, magnesium-iron-chlorine-rich components, and hydrated calcium sulfates, respectively. Composition of a cross-cutting dike-like feature is consistent with sedimentary intrusion. The geochemistry of these sedimentary rocks provides further evidence for diverse depositional and diagenetic sedimentary environments during the early history of Mars.
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Applications of Imaging Biomarkers in the Early Clinical Development of Central Nervous System Therapeutic Agents. Clin Pharmacol Ther 2012; 91:315-20. [DOI: 10.1038/clpt.2011.286] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Testing Mars-inspired operational strategies for semi-autonomous rovers on the Moon: The GeoHeuristic Operational Strategies Test in New Mexico. MARS (LOS ANGELES, CALIF.) 2011; 6:13-31. [PMID: 29309066 PMCID: PMC5754929 DOI: 10.1555/mars.2011.0002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background We tested the science operational strategy used for the Mars Exploration Rover (MER) mission on Mars to determine its suitability for conducting remote geology on the Moon by conducting a field test at Cerro de Santa Clara, New Mexico. This region contains volcanic and sedimentary products from a variety of provenances, mimicking the variety that might be found at a lunar site such as South Pole-Aitken Basin. Method At each site a Science Team broke down observational “days” into a sequence of observations of features and targets of interest. The number, timing, and sequence of observations was chosen to mimic those used by the MERs when traversing. Images simulating high-resolution stereo and hand lens-scale images were taken using a professional SLR digital camera; multispectral and XRD data were acquired from samples to mimic the availability of geochemical data. A separate Tiger Team followed the Science Team and examined each site using traditional terrestrial field methods, facilitating comparison between what was revealed by human versus rover-inspired methods. Lessons Learned We conclude from this field test that MER-inspired methodology is not conducive to utilizing all acquired data in a timely manner for the case of any lunar architecture that involves the acquisition of rover data in near real-time. We additionally conclude that a methodology similar to that used for MER can be adapted for use on the Moon if mission goals are focused on reconnaissance. If the goal is to locate and identify a specific feature or material, such as water ice, a different methodology will likely be needed.
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Iron mineralogy and aqueous alteration from Husband Hill through Home Plate at Gusev Crater, Mars: Results from the Mössbauer instrument on the Spirit Mars Exploration Rover. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008je003201] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Geochemical properties of rocks and soils in Gusev Crater, Mars: Results of the Alpha Particle X-Ray Spectrometer from Cumberland Ridge to Home Plate. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008je003195] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Structure, stratigraphy, and origin of Husband Hill, Columbia Hills, Gusev Crater, Mars. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007je003041] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Prostate cancer tissue is masked by bicalutamide: a case report. Eur J Med Res 2007; 12:212-5. [PMID: 17513193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
Prostate cancer is the most common malignant tumor in men. Recently, a slightly decreased frequency of margin positivity following neoadjuvant bicalutamide treatment due to tumor shrinkage was reported. Trials investigating other anti-androgens in the past also reported lower frequencies of surgical margin positivity, but patients outcome has not improved. In this case, local recurrence was confirmed by needle biopsy in a patient five years following radical prostatectomy for prostate adenocarcinoma. After therapy with 50 mg bicalutamide for a month, the tumour was resected. Despite of detailed histological work-up and immunohistochemistry cancer suspicious lesions were not found. We think that bicalutamide may be capable of masking prostate cancer cells.
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Mössbauer mineralogy of rock, soil, and dust at Meridiani Planum, Mars: Opportunity's journey across sulfate-rich outcrop, basaltic sand and dust, and hematite lag deposits. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2006je002791] [Citation(s) in RCA: 183] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Aggressive angiomyxoma of the prostate mimicking benign prostatic hyperplasia. Eur J Med Res 2006; 11:167-9. [PMID: 16720282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023] Open
Abstract
Aggressive angiomyxoma (AAM) is a locally invasive soft tissue tumor with a high risk of local recurrence but without metastatic spread. The mesenchymal tumor is relatively site-specific and has a peak incidence in females in their 2nd or 4th decade. Only few cases in males have been reported in the literature. We describe what we think is the first case of an aggressive angiomyxoma arising in the prostate presenting with classical symptoms of benign prostatic hyperplasia.
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Central nervous system drug development: an integrative biomarker approach toward individualized medicine. NeuroRx 2006; 2:683-95. [PMID: 16489375 PMCID: PMC1201325 DOI: 10.1602/neurorx.2.4.683] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Drug development for CNS disorders faces the same formidable hurdles as other therapeutic areas: escalating development costs; novel drug targets with unproven therapeutic potential; and health care systems and regulatory agencies demanding more compelling demonstrations of the value of new drug products. Extensive clinical testing remains the core of registration of new compounds; however, traditional clinical trial methods are falling short in overcoming these development hurdles. The most common CNS disorders targeted for drug treatment are chronic, slowly vitiating processes manifested by highly subjective and context dependent signs and symptoms. With the exception of a few rare familial degenerative disorders, they have ill-defined or undefined pathophysiology. Samples selected for treatment trials using clinical criteria are inevitably heterogeneous, and dependence on traditional endpoints results in early proof-of-concept trials being long and large, with very poor signal to noise. It is no wonder that pharmaceutical and biotechnology companies are looking to biomarkers as an integral part of decision-making process supported by new technologies such as genetics, genomics, proteomics, and imaging as a mean of rationalizing CNS drug development. The present review represent an effort to illustrate the integration of such technologies in drug development supporting the path of individualized medicine.
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Statistical methods for the validation of questionnaires--discrepancy between theory and practice. Methods Inf Med 2006; 45:409-13. [PMID: 16964357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
OBJECTIVES Questionnaires used in epidemiological studies should be validated. However, unclarity exists about the appropriate statistical methods and interpretation of validation studies. Thus, we investigated the theory and practice of statistical evaluation approaches. METHODS Using three platforms, a literature review, own simulations, and a validation study performed by ourselves, we worked out relevant limitations, advantages, and new important aspects of evaluation methods. RESULTS Our systematic literature review, based on physical activity questionnaires, revealed that correlation coefficients are still the common approach in validation studies, found in 41 of 46 reviewed publications (89.1%). This practice has been criticized in the theoretically oriented literature for more than 20 years. Appropriate evaluation methods as recommended by Bland and Altman were found in only ten publications (21.7%). We showed that serious bias in questionnaires can be revealed by Bland-Altman plots but may remain undetected by correlation coefficients. With our simulations we refuted the argument that correlation coefficients properly investigate whether a questionnaire ranks the subjects sufficiently well. Further, with Bland-Altman analyses we could evaluate differential errors with respect to case-control status in our validation study. Yet, this was not possible with correlation coefficients, because they generally do not identify systematic bias. In addition, we show a potential pitfall in the interpretation of Bland-Altman plots that might occur in specific rare instances. CONCLUSIONS The commonly used correlation approach can yield misleading conclusions in validation studies. A more frequent and proper use of the Bland-Altman methods would be desirable to improve epidemiological data quality.
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Seed quality QTL in a prominent soybean population. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2004; 109:552-61. [PMID: 15221142 DOI: 10.1007/s00122-004-1661-5] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2003] [Accepted: 03/08/2004] [Indexed: 05/24/2023]
Abstract
Soybean [Glycine max (L.) Merr.] is a versatile crop due to its multitude of uses as a high protein meal and vegetable oil. Soybean seed traits such as seed protein and oil concentration and seed size are important quantitative traits. The objective of this study was to identify representative protein, oil, and seed size quantitative trait loci (QTL) in soybean. A recombinant inbred line (RIL) population consisting of 131 F6-derived lines was created from two prominent ancestors of North American soybeans ('Essex' and 'Williams') and the RILs were grown in six environments. One hundred simple sequence repeat (SSR) markers spaced throughout the genome were mapped in this population. There were a total of four protein, six oil, and seven seed size QTL found in this population. The QTL found in this study may assist breeders in marker-assisted selection (MAS) to retain current positive QTL in modern soybeans while simultaneously pyramiding additional QTL from new germplasm.
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Soybean Cyst Nematode Reduces Soybean Yield Without Causing Obvious Aboveground Symptoms. PLANT DISEASE 2003; 87:623-628. [PMID: 30812850 DOI: 10.1094/pdis.2003.87.6.623] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Field experiments were conducted at locations in northern and southern Illinois, central Iowa, and central Missouri from 1997 to 1999 to investigate the effects of Heterodera glycines on soybean growth, development, and yield. A wide range of infestation levels was present at all locations. Two locally adapted cultivars, one resistant to H. glycines, were grown at each location. Cultivars were planted in alternating four-row strips with 76 cm between rows. For each cultivar, 20 1-m-long single-row plots were sampled every 2 weeks starting 4 weeks after planting. Infection by H. glycines reduced plant height and leaf and stem weight on the resistant cultivars in the first 12 weeks after planting, and delayed pod and seed development 12 to 14 weeks after planting. Biomass accumulation was not reduced on the susceptible cultivars until 10 weeks after planting; reduction in pod and seed development occurred throughout the reproductive stages. Susceptible cultivars produced significantly lower yields than resistant cultivars, but the yield reductions were not accompanied by visually detectable symptoms.
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Quantitative trait loci in Two Soybean Recombinant Inbred Line Populations Segregating for Yield and Disease Resistance. CROP SCIENCE 2002; 42:271-277. [PMID: 11756285 DOI: 10.2135/cropsci2002.2710] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Molecular makers linked to quantitative trait loci (QTL) can assist soybean [Glycine max (L.) Merr.] breeders to combine traits of low heritability, such as yield, with disease resistance. The objective of this study was to identify markers linked to yield QTL in two recombinant inbred line (RIL) populations ['Essex' x 'Forrest' (ExF; n = 100) and 'Flyer' x 'Hartwig' (FxH; n = 94)] that also segregate for soybean cyst nematode (SCN) resistance genes (rhg1 and Rhg4). Each population was yield tested in four environments between 1996 and 1999. The resistant parents produced lower yields. Heritability of yield across four environments was 47% for ExF and 57% for FxH. Yield was normally distributed in both populations. High yielding, SCN resistant transgressive segregants were not observed. In the ExF RIL population, 134 microsatellite markers were compared against yield by ANOVA and MAPMAKER QTL. Regions associated with yield were identified by SATT294 on linkage group (LG.) C1 (P = 0.006, R(2) = 10%), SATT440 on LG. I (P = 0.007, R(2) = 10%), and SATT337 on LG. K (P = 0.004, R(2) = 10%). Essex provided the beneficial allele at SATT337. Mean yields among FxH RILs were compared against 33 microsatellite markers from LG. K. In addition 136 markers from randomly selected LGs were compared with extreme phenotypes by bulk segregant analysis. Two regions on LG. K (20 cM apart) associated with yield were identified by SATT326 (P = 0.0004, R(2) = 15%) and SATT539 (P = 0.0008, R(2) = 14%). Flyer provided both beneficial alleles. Both populations revealed a yield QTL in the interval (5 cM) between SATT337 and SATT326. These populations may share a common allele for yield in this region, given that about 40% of Flyer genome derived from Essex.
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Abstract
Dynamic susceptibility contrast magnetic resonance imaging (DSC MRI) can be used to generate high resolution maps of cerebral blood volume (CBV). To determine the test-retest reliability, CBV was measured in eight volunteers on two occasions, separated by 4 weeks. The mean ratio (scan 2/scan 1) for 72 cortical regions of interest (ROIs) was 1.03, with a coefficient of variation of 14%. The correlation between the first and second scans was 0.73 (p < 0.0001; 95%). In five hand-drawn ROIs, the mean ratio was 1.08, with a coefficient of variation of 12%. The correlation between scans was 0.84 (p < 0.0001). The data presented here support the hypothesis that DSC MRI CBV mapping has acceptable test-retest reliability.
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Abstract
BACKGROUND Regional brain activity was measured before and after electroconvulsive therapy (ECT) using [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET). METHODS 6 patients (4 females) with major depression were free of psychotropic medications for at least 2 weeks prior to baseline FDG scans. Patients were treated with bifrontotemporal ECT, and posttreatment scans were obtained after the last treatment. RESULTS A region of interest (ROI) analysis of absolute metabolic rate showed a decrease in CMRglu after ECT in all 61 regions examined. In 17 of the 61 regions, the decrease was significant at the p < 0.05 level. In the right parietal lobe, and the right anterior and left posterior frontal lobes, the decrease in CMRglu significantly correlated with the decrease in Hamilton Depression Rating Scale (HDRS) scores (r = 0.83, 0.82, and 0.84, respectively). The analysis of CMRglu normalized to global metabolic rate showed significant increases in 8 of 61 regions, including basal ganglia, upper brainstem, and occipital lobe. DISCUSSION The decreases in global glucose metabolism and correlation of changes in frontal metabolism with decreases in HDRS are consistent with earlier brain imaging studies of ECT. The relative increases in CMRglu observed in regions with known dopaminergic innervation (caudate and upper brainstem) have not been previously reported.
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Temperature Effects on Race Determination in Heterodera glycines. J Nematol 2000; 32:349-355. [PMID: 19270988 PMCID: PMC2620468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
Currently there are 16 possible races for Heterodera glycines, and these are differentiated based on ability of a nematode population to develop on a set of four differential soybean genotypes. Because results are based on numbers of nematode females that develop to a specific stage rather than on the reproductive capability of these females, race determinations based on female indices may not represent results obtained after several reproductive cycles of H. glycines. Counting numbers of eggs and juveniles, and then developing corresponding indices, would allow reproduction to be considered in making race determinations. Our objectives were to compare the present race identification scheme for H. glycines based on female indices with those using egg and juvenile indices and to examine the effect of temperature on race designations using female, egg, and juvenile indices. Race designations for H. glycines populations from two locations in Illinois were determined at 20, 27, and 30 degrees C in a water bath. The numbers of females, eggs, and juveniles (at 19 days) were recorded, and an index based on each life stage was calculated. Race determinations based on female, egg, or juvenile indices were inconsistent when conducted at 20 degrees C, which demonstrates that this temperature is not suitable for identifying races of H. glycines. However race designations at 27 and 30 degrees C were consistent for all three indices. This indicates that counting females, eggs, or juveniles should be equally reliable when race determinations are conducted at these two temperatures, and choice of method would depend on investigator preference or research objective.
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Patient compliance to a new enteric-coated weekly formulation of fluoxetine during continuation treatment of major depressive disorder. J Clin Psychiatry 2000; 61:928-32. [PMID: 11206598 DOI: 10.4088/jcp.v61n1207] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND A new formulation of enteric-coated fluoxetine given once weekly could be a useful option for the long-term treatment of depression, but compliance to once-weekly fluoxetine treatment has not been assessed. METHOD Patients were adults from the United Kingdom who had responded to fluoxetine treatment for a current episode of depression (DSM-IV criteria). In the baseline assessment phase, all patients (N = 117) were continued on 20 mg of open-label fluoxetine once daily for 4 weeks. In the follow-up phase, patients (N = 109) were randomly assigned to once-weekly or once-daily fluoxetine for 3 months. Patient compliance was monitored by electronic devices during both phases of the study. RESULTS Compliance to once-weekly fluoxetine treatment was higher than compliance to once-daily fluoxetine (85.9% vs. 79.4%, respectively). CONCLUSION Once-weekly fluoxetine treatment allows for new flexibility for both the clinician and the patient, and this study alleviates the concern that patients will forget weekly doses.
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The efficacy and safety of a new enteric-coated formulation of fluoxetine given once weekly during the continuation treatment of major depressive disorder. J Clin Psychiatry 2000; 61:851-7. [PMID: 11105738 DOI: 10.4088/jcp.v61n1107] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND A simple, once-weekly dosing regimen could be a convenient alternative for many patients during long-term treatment of depression. Such a strategy might also be effective for improving medication compliance and the outcome of continuation treatment. The safety and effectiveness of a new formulation of enteric-coated fluoxetine (90 mg) given once weekly was tested during the continuation treatment of major depressive disorder. METHOD Patients meeting DSM-IV criteria for major depressive disorder with modified 17-item Hamilton Rating Scale for Depression (HAM-D-17) scores > or = 18 and Clinical Global Impressions-Severity of Illness scale (CGI-S) scores > or = 4 were treated 13 weeks with open-label 20 mg/day of fluoxetine in a multicenter U.S. study. Responders (N = 501) were randomly assigned to receive 20 mg of fluoxetine daily, placebo, or 90 mg of enteric-coated fluoxetine weekly for 25 weeks of double-blind continuation treatment. The primary efficacy measure was the percentage of patients who relapsed. Time to relapse was tested over the 25-week continuation period using log-rank analyses of the Kaplan-Meier estimates of relapse rates. Additional analyses of efficacy included comparison of change from baseline to endpoint for the HAM-D-17, CGI-S, and HAM-D-28 subscales by last observation carried forward (LOCF). Safety measures included comparison of treatment-emergent adverse events, both spontaneous and solicited (using the Association for Methodology of Documentation in Psychiatry-Module 5), vital signs, and laboratory measures. RESULTS Relapse rates for patients assigned to fluoxetine, either 20 mg daily or 90 mg weekly, were significantly lower than for placebo by log-rank analysis and LOCF analyses of secondary efficacy measures. Efficacy did not significantly differ between the 2 active drug groups by these measures. Enteric-coated fluoxetine at a once-weekly dose of 90 mg was well tolerated, and its safety profile was similar to that of daily 20 mg of fluoxetine. CONCLUSION The formulation of enteric-coated fluoxetine taken once weekly is effective, safe, and well tolerated for continuation treatment of depression in patients who responded to acute treatment with 20 mg/day of fluoxetine. Monitoring during long-term treatment for evidence of sustained remission is important regardless of dosing regimen.
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Abstract
OBJECTIVE This study tested whether a relationship exists between concentration and response following discontinuation of selective serotonin reuptake inhibitors. METHOD Eight patients with remitted major depression who were taking 20 mg/day of either fluoxetine or paroxetine underwent placebo substitution for 3 days. Serum drug and brain fluorine levels were obtained before and after placebo substitution. RESULTS With placebo substitution, a mean of 88% (SD=13%) of brain fluorine signal from fluoxetine (plus fluorinated metabolites) remained, compared with a mean of 38% (SD=17%) of the brain fluorine signal from paroxetine (plus fluorinated metabolites). Among patients taking paroxetine, adverse events during placebo substitution correlated highly with steady-state brain drug levels. CONCLUSIONS The correlation of clinical effects with brain drug levels in the paroxetine group suggests that relationships between drug response and brain drug concentrations merit further investigation.
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Abstract
STUDY OBJECTIVE To determine the relationship between aspergillus recovery from the airways of lung transplant recipients and the development of endobronchial abnormalities. DESIGN Retrospective case series. SETTING Tertiary-care hospital. PATIENTS All patients who underwent lung transplantation between December 1991 and June 1999. MEASUREMENTS AND RESULTS The study cohort included 38 patients. The primary end point was the bronchoscopic identification of an endobronchial abnormality. Aspergillus was isolated from the lungs of nine patients (23.7%). Most of these isolates occurred early after transplantation (mean, 8 weeks). Endobronchial abnormalities arose in seven of the patients (18.4%) and manifested as either exuberant granulation tissue or stricture formation. Six of the 9 (66.6%) patients with aspergillus developed airway lesions, compared to 1 of the 29 patients (3.4%) without aspergillus (p = 0.0002). Endobronchial abnormalities were 19.3 times more likely to occur in patients in whom aspergillus had previously been isolated. As a screening test for the subsequent diagnosis of an airway complication, the recovery of aspergillus had a sensitivity and specificity of 85.7% and 90.3%, respectively. These aspergillus-related endobronchial abnormalities were clinically relevant as evidenced by a mean increase of 25.9% in the FEV(1) after bronchoscopic intervention. CONCLUSION The early isolation of aspergillus from the airways of lung transplant recipients identifies patients at increased risk for the development of clinically significant endobronchial abnormalities.
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Root Colonization of Soybean Cultivars in the Field by Fusarium solani f. sp. glycines. PLANT DISEASE 1999; 83:1155-1159. [PMID: 30841142 DOI: 10.1094/pdis.1999.83.12.1155] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Soybean sudden death syndrome (SDS), caused by Fusarium solani f. sp. glycines, is a problem in some soybean-growing areas in the United States. Resistance is an important control strategy. In this study, root colonization of six soybean cultivars by F. solani f. sp. glycines was determined. Cultivars included susceptible P3981, CM497, and Spencer and field resistant LS90-1920, Pharaoh, and Ripley. All cultivars were tested in field experiments at different locations in southern Illinois in 1997 and 1998. Roots were collected at six sampling times and were dried and ground to isolate and enumerate the pathogen on a selective medium. SDS foliar disease index (FDX), the area under the F. solani f. sp. glycines population curve (AUPC), the incidence of colonized roots at 45 days after planting (RCI45), and the root colonization rate (RCR) were used to compare cultivars. FDX on the three resistant cultivars was significantly lower than on the three susceptible cultivars. Means of AUPC on the three resistant cultivars were significantly lower than those on the susceptible CM497 and P3981. RCI45 of Pharaoh was significantly lower than those of P3981 and Spencer. RCRs of all three resistant cultivars were significantly lower than that of P3981, and RCR of Ripley was also significantly lower than that of CM497. Based on combination of all cultivars, AUPC was significantly correlated with RCI45 and RCR.
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Direct correlation between hyperoxaluria/oxalate stone disease and the absence of the gastrointestinal tract-dwelling bacterium Oxalobacter formigenes: possible prevention by gut recolonization or enzyme replacement therapy. J Am Soc Nephrol 1999; 10 Suppl 14:S334-40. [PMID: 10541258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
Oxalobacter formigenes is a specific oxalate-degrading, anaerobic bacterium inhabiting the gastrointestinal tracts of vertebrates, including humans. This bacterium maintains an important symbiotic relationship with its host by regulating oxalate homeostasis, primarily by preventing enteric absorption. Increased absorption of oxalate can lead to multiple complications associated with hyperoxaluria, especially recurrent calcium oxalate urolithiasis. Detection of O. formigenes in the gastrointestinal tract has attracted attention because the absence of this bacterium appears to be a risk factor for development of hyperoxaluria and/or recurrent calcium oxalate kidney stone disease. In the present study, epidemiologic studies with patients at high risk for calcium oxalate urolithiasis showed a direct correlation between the number of recurrent kidney stone episodes and the lack of O. formigenes colonization. As expected, the lack of O. formigenes revealed a clear association with prophylactic antibiotic therapy. To confirm the importance of O. formigenes in regulating hyperoxaluria, laboratory rats known to be noncolonized were colonized with live bacteria or treated with a preparation of oxalate-degrading enzymes derived from O. formigenes to determine any subsequent increased resistance to high oxalate challenge. Rats receiving either bacteria or enzyme replacement therapy excreted far lower levels of oxalate, did not develop the crystalluria observed with control rats, and resisted the formation of calcium oxalate crystals in their nephrons. These observations, taken together, support the concept that O. formigenes is important in maintaining oxalate homeostasis, that its absence from the gut increases the risk for hyperoxaluria and recurrent kidney stone disease, and that replacement therapy is an efficient procedure to prevent hyperoxaluria and its complications.
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Aspects of fetal thyroid dose following iodine-131 administration during early stages of pregnancy in patients suffering from benign thyroid disorders. EUROPEAN JOURNAL OF NUCLEAR MEDICINE 1999; 26:1453-7. [PMID: 10552087 DOI: 10.1007/s002590050478] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Detrimental effects on the thyroid of the developing fetus as a result of iodine-131 treatment for thyrotoxicosis of the mother in the first trimester of pregnancy are discussed. Dose estimations under typical clinical circumstances yield a fetal thyroid dose of 100- 450 Sv. This dose may increase considerably if the blood concentration of (131)I in the mother remains high. Under such circumstances there may be fetal thyroid dysfunction, which can lead to severe abnormalities.
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Cerebral glucose metabolic and plasma catecholamine responses to the alpha(2) adrenoceptor antagonist ethoxyidazoxan given to healthy volunteers. Psychopharmacology (Berl) 1999; 146:119-27. [PMID: 10525746 DOI: 10.1007/s002130051097] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
RATIONALE Methods that test for the central effects of alpha(2)-adrenoceptor antagonists can facilitate the clinical development of such compounds. Recently we evaluated the effects of idazoxan (IDX), an alpha(2)-adrenoceptor antagonist with high affinity for imidazoline sites, on a variety of measures potentially sensitive to blockade of alpha(2)-adrenoceptors including regional brain glucose metabolic rate. OBJECTIVE To test whether these effects on brain metabolic rate could have been mediated by imidazoline binding sites, single dose challenges of 9 or 12 mcg/kg ethoxyidazoxan (ETX; an alpha(2)-adrenoceptor antagonist which does not bind to imidazoline sites) were given to healthy male volunteers. METHODS The effects on brain glucose metabolism, blood pressure, catecholamines, and behavior were assessed. RESULTS Blood pressure increased 10-15% after both doses. Plasma catecholamines increased 2- to 2.5-fold and responses were dose dependent. There was no evidence of either dose being anxiogenic. Both doses of ETX produced diffuse increases in brain glucose metabolism. CONCLUSIONS Brain glucose metabolic responses were more widespread and monotonic than we had observed with IDX. ETX also produced robust increases in glucose metabolism in cerebellum. While we were unable to exclude the possibility that some of the brain metabolic responses we had observed with IDX were mediated by imidazoline sites, ETX may be sufficiently distinct from IDX in alpha(2)-adrenoceptor affinity that differences in acute metabolic responses occurred.
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Foveal outer retinal function in eyes with unexplained visual symptoms or acuity loss. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 1998; 116:1161-8. [PMID: 9747673 DOI: 10.1001/archopht.116.9.1161] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To determine whether foveal outer retinal dysfunction is common in eyes with unexplained visual symptoms or acuity loss. DESIGN Prospective study. PARTICIPANTS Seventy-three eyes of 44 consecutive patients with unexplained visual symptoms or acuity loss, 39 eyes of 39 control subjects, and 12 eyes of 7 patients with known maculopathy. INTERVENTION Foveal cone electroretinography (ERG) and letter recognition perimetry. MAIN OUTCOME MEASURES Foveal cone ERG data. RESULTS Abnormal foveal cone ERG data were recorded in 35 (48%) of 73 eyes (23 [52%] of 44 patients). Among these 35 eyes, amplitude was lower than in normal controls (P<.001) and was correlated with visual acuity and the number of letter recognition perimetry errors (P<.05 for both). The latter was higher in eyes with abnormal retinal responses than in symptomatic eyes with normal responses (P<.01). However, initial symptoms, visual acuity, and macular appearance did not differentiate between these 2 groups. Foveal cone ERG test vs retest data showed consistent results. CONCLUSION Foveal outer retinal dysfunction is a common underlying mechanism of previously unexplained visual symptoms or acuity loss. Foveal cone ERG testing should be considered early in the evaluation of eyes with this presentation.
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Treatment of major depression: selection of initial drug. MODERN PROBLEMS OF PHARMACOPSYCHIATRY 1997; 25:1-16. [PMID: 9344366 DOI: 10.1159/000061658] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Abstract
Seven male and five female volunteers underwent double-blind infusions of the alpha 2-adrenoceptor antagonist idazoxan (100 and 200 micrograms/mg) and placebo in random order. Blood pressure, plasma norepinephrine, growth hormone and subjective responses were measured. The higher dose of idazoxan produced increases in blood pressure, norepinephrine and growth hormone and slight increases in anxiety. Both subject age and sex appeared to influence the magnitude of responses.
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HIV update. VIRGINIA MEDICAL QUARTERLY : VMQ 1997; 124:105-7. [PMID: 9100473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Gender differences in brain metabolic and plasma catecholamine responses to alpha 2-adrenoceptor blockade. Neuropsychopharmacology 1997; 16:298-310. [PMID: 9094148 DOI: 10.1016/s0893-133x(96)00264-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
alpha 2-Adrenergic receptors modulate the release of several neurotransmitters implicated in the treatment and pathophysiology of mood and anxiety disorders. Significant sex differences occur in the prevalence of both disorders. To test whether gender affects alpha 2 function, the plasma catecholamine and brain metabolic responses to alpha 2 blockade were measured in male and female volunteers. Ten female and thirteen male volunteers underwent [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) scans before and after infusion of idazoxan (200 micrograms/kg). Measures of plasma catecholamines, blood pressure, and anxiety were obtained. Norepinephrine responses were larger in males. Women showed global increases in metabolism, whereas males had no global changes and some regional decreases in FDG uptake following idazoxan administration. The differences in norepinephrine increases are consistent with previously reported effects of gender on sympathetic activation. The PET data suggest gender differences in responses to alpha 2-receptor blockade in brain as well.
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Acute alpha 2 blockade by idazoxan increases insulin and lowers plasma glucose during positron emission tomography. PSYCHOPHARMACOLOGY BULLETIN 1997; 33:253-9. [PMID: 9230639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The sympathetic nervous system can modulate glucose levels through a variety of mechanisms, including inhibition of insulin release by alpha2-adrenergic receptors. Such effects could potentially confound measurements of brain glucose metabolism during studies of the central actions of sympathomimetic drugs. Plasma glucose, insulin, and sympathetic responses to alpha2 blockade were measured following infusion of idazoxan, a selective alpha2 antagonist, or placebo, in 33 healthy volunteers (idazoxan: n = 23, placebo: n = 10). These measures were compared with estimates of global brain metabolism obtained from positron emission tomography (PET) scans before and after the infusion. Glucose levels fell and fractional levels of insulin rose after idazoxan, compared with placebo. Relative increases in insulin correlated with increases in epinephrine after active drug. The increases in insulin are consistent with the hypothesized role of alpha2-adrenoceptors in regulating insulin release. Estimates of global brain glucose metabolism did not appear to be influenced by the modest changes in plasma glucose.
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Cerebral glucose metabolism during pharmacologic studies: test-retest under placebo conditions. J Nucl Med 1996; 37:1142-9. [PMID: 8965185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
UNLABELLED The reliability of serial [18F]fluorodeoxyglucose (FDG) PET scans for psychopharmacologic studies was tested by using placebo infusions. METHODS FDG scans were obtained before and after a 30 min placebo infusion (n = 10; Group 1) or after each of two bolus infusions with placebo (n = 8; Group 2). Subjects performed a continuous performance task (CPT) during each scan. Cardiovascular measures and ratings of anxiety were obtained in all subjects. Samples for determination of plasma norepinephrine (NE) were taken at multiple time points in Group 1. RESULTS A slight increase in apparent global metabolism occurred between scans in both Groups 1 and 2. A few regions significantly increased in both groups. While an apparent increase in sympathetic activity occurred during the placebo infusion, neither NE levels, anxiety ratings nor cardiovascular measures correlated with global or regional FD6 uptake. CONCLUSION Test-retest differences of global and regional glucose metabolism were highly consistent across two experimental designs. While increases in cerebral glucose metabolism appeared to occur during the second scan, differences between scans were small. This method may offer advantages for selected psychopharmacologic studies.
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Size-dependent two-photon excitation spectroscopy of CdSe nanocrystals. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:12629-12632. [PMID: 9982928 DOI: 10.1103/physrevb.53.12629] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Electrochemical tuning of the lifetime of the CO stretching vibration for CO/Pt(111). J Chem Phys 1996. [DOI: 10.1063/1.470938] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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