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Liu H, Wang P, Xu F, Nie Q, Yan S, Zhang Z, Zhang Y, Jiang C, Qin X, Pang Y. The Hydrophilic Metabolite UMP Alleviates Obesity Traits through a HIF2α-ACER2-Ceramide Signaling Axis. Adv Sci (Weinh) 2024:e2309525. [PMID: 38460165 DOI: 10.1002/advs.202309525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 02/09/2024] [Indexed: 03/11/2024]
Abstract
Metabolic abnormalities contribute to the pathogenesis of obesity and its complications. Yet, the understanding of the interactions between critical metabolic pathways that underlie obesity remains to be improved, in part owing to the lack of comprehensive metabolomics studies that reconcile data from both hydrophilic and lipophilic metabolome analyses that can lead to the identification and characterization of key signaling networks. Here, the study conducts a comprehensive metabolomics analysis, surveying lipids and hydrophilic metabolites of the plasma and omental adipose tissue of obese individuals and the plasma and epididymal adipose tissue of mice. Through these approaches, it is found that a significant accumulation of ceramide due to inhibited sphingolipid catabolism, while a significant reduction in the levels of uridine monophosphate (UMP), is critical to pyrimidine biosynthesis. Further, it is found that UMP administration restores sphingolipid homeostasis and can reduce obesity in mice by reversing obesity-induced inhibition of adipocyte hypoxia inducible factor 2a (Hif2α) and its target gene alkaline ceramidase 2 (Acer2), so as to promote ceramide catabolism and alleviate its accumulation within cells. Using adipose tissue Hif2α-specific knockout mice, the study further demonstrates that the presence of UMP can alleviate obesity through a HIF2α-ACER2-ceramide pathway, which can be a new signaling axis for obesity improvement.
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Affiliation(s)
- Huiying Liu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing, 100191, China
- Center for Obesity and Metabolic Disease Research, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Pengcheng Wang
- Center of Basic Medical Research, Institute of Medical Innovation and Research, Third Hospital, Peking University, Beijing, 100191, China
| | - Feng Xu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing, 100191, China
- Center for Obesity and Metabolic Disease Research, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
- Clinical Pharmacology and Pharmacometrics, Janssen China Research & Development, Beijing, 100191, China
| | - Qixing Nie
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing, 100191, China
- Center for Obesity and Metabolic Disease Research, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
- State Key Laboratory of Food Science and Resources, China-Canada Joint Lab of Food Science and Technology, Key Laboratory of Bioactive Polysaccharides of Jiangxi Province, Nanchang University, Nanchang, 330013, China
| | - Sen Yan
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, State Key Laboratory of Female Fertility Preservation and Promotion, Peking University Third Hospital, Beijing, 100191, China
| | - Zhipeng Zhang
- General Surgery Department, Third Hospital, Peking University, Beijing, 100191, China
| | - Yi Zhang
- General Surgery Department, Third Hospital, Peking University, Beijing, 100191, China
| | - Changtao Jiang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing, 100191, China
- Center for Obesity and Metabolic Disease Research, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
- Center of Basic Medical Research, Institute of Medical Innovation and Research, Third Hospital, Peking University, Beijing, 100191, China
- Department of Immunology, School of Basic Medical Sciences, NHC Key Laboratory of Medical Immunology, Peking University, Beijing, 100191, China
| | - Xiaomei Qin
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing, 100191, China
| | - Yanli Pang
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, State Key Laboratory of Female Fertility Preservation and Promotion, Peking University Third Hospital, Beijing, 100191, China
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Wong KS, Barletta JA. Challenges in Encapsulated Follicular-Patterned Tumors: How Much Is Enough? Evaluation of Nuclear Atypia, Architecture, and Invasion. Surg Pathol Clin 2023; 16:27-44. [PMID: 36739165 DOI: 10.1016/j.path.2022.09.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Thyroid pathology is notoriously fraught with high interobserver variability, and follicular-patterned tumors are among some of the most challenging to assess accurately and reproducibly. Given that encapsulated or well-circumscribed follicular-patterned tumors often have similar molecular profiles, that is, frequent RAS or RAS-like alterations, the diagnosis usually relies on histopathologic examination alone. Unfortunately, many of the features that are used for diagnosis and prognosis of these tumors have long been controversial and frequently debated topics, both due to their subjectivity and their evolving (or not yet resolved) definitions. In more recent years, the introduction of noninvasive follicular thyroid neoplasm with papillary-like nuclear features has added further complexity to this discussion. In particular, the criteria and significance of nuclear features of papillary thyroid carcinoma, architectural patterns, and invasive growth still pose significant diagnostic challenges and confusion. This review explores some of the challenges in evaluating encapsulated follicular-patterned tumors, focusing on those histologic elements.
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Affiliation(s)
- Kristine S Wong
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Justine A Barletta
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
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Terao Y, Kumagai Y, Suzuki I, Tsuchiya T, Ukai M, Yokoya A, Fujii K, Fukuda Y, Saitoh Y. X-ray induced luminescence spectroscopy for DNA damaging intermediates aided by a monochromatic synchrotron radiation. Int J Radiat Biol 2023; 99:89-94. [PMID: 34402379 DOI: 10.1080/09553002.2021.1967506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE To identify the bonding sites of initial radiation interaction with DNA and to trace the following chemical reaction sequences on the pathway of damage induction, we carry out a spectroscopy XIL (X-ray induced luminescence) using soft X-ray synchrotron radiation. This is a nondestructive analysis of the excited intermediate species produced in a molecular mechanism on the damage induction pathway. MATERIALS AND METHODS We introduce aqueous samples of UMP (uridine-5'-monophosphate) in the vacuum by the use of a liquid micro-jet technique. The luminescence in the region of UV-VIS (from visible to ultraviolet) radiation induced after the absorption of monochromatic soft X-ray by aqueous UMP is measured with sweeping the soft X-ray energy in the region of 370-560 eV. RESULTS The enhanced XIL intensities for aqueous UMP in the region of soft X-ray of 410-530 eV (in "water window" region) are obtained. The enhancement of XIL intensities in the UV-VIS region, relative to the water control, is explained by the excitation and ionization of a K-shell electron of nitrogen atoms in the uracil moiety. The enhanced XIL intensities do not match the structure of XANES (X-ray absorption near-edge structure) of the aqueous UMP. This suggests that the XIL intensities reflect the quantum yields of luminescence, or the quantum yields for conversion by UMP of an absorbed X-ray into UV-VIS radiation. In this paper, spectra of luminescence are shown to be resolved by combining low pass filters. The filtered luminescence spectra are obtained at the center of gravity (λc) of the band pass wavelength regions at λc = 270nm, 295 nm, 340 nm, 385 nm, 450 nm, and 525 nm., which show a trend similar to the fluorescence of nucleobases induced by ultraviolet radiation. CONCLUSION It is concluded that the origin of the observed XIL is the hydrated uracil moiety in aqueous UMP, decomposition of which is suppressed by the migration of excess charge and internal energy after the double ionization due to Auger decay.
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Affiliation(s)
- Yusaku Terao
- Department of Applied Physics, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Yoshiaki Kumagai
- Department of Applied Physics, Tokyo University of Agriculture and Technology, Tokyo, Japan.,Institute of Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Issei Suzuki
- Department of Applied Physics, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Takahiro Tsuchiya
- Department of Applied Physics, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Masatoshi Ukai
- Department of Applied Physics, Tokyo University of Agriculture and Technology, Tokyo, Japan.,Institute of Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Akinari Yokoya
- Institute of Quantum Life Science, National Institute for Quantum and Radiological Science, Ibaraki, Japan
| | - Kentaro Fujii
- Institute of Quantum Life Science, National Institute for Quantum and Radiological Science, Ibaraki, Japan.,Quantum beam Science Research Directorate, National Institute for Quantum and Radiological Science, Hyogo, Japan
| | - Yoshihiro Fukuda
- Synchrotron Radiation Research Center, Japan Atomic Energy Agency, Hyogo, Japan
| | - Yuji Saitoh
- Synchrotron Radiation Research Center, Japan Atomic Energy Agency, Hyogo, Japan
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Brandt MJV, Nijboer CH, Nessel I, Mutshiya TR, Michael-Titus AT, Counotte DS, Schipper L, van der Aa NE, Benders MJNL, de Theije CGM. Nutritional Supplementation Reduces Lesion Size and Neuroinflammation in a Sex-Dependent Manner in a Mouse Model of Perinatal Hypoxic-Ischemic Brain Injury. Nutrients 2021; 14:176. [PMID: 35011052 PMCID: PMC8747710 DOI: 10.3390/nu14010176] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/21/2021] [Accepted: 12/24/2021] [Indexed: 12/22/2022] Open
Abstract
Perinatal hypoxia-ischemia (HI) is a major cause of neonatal brain injury, leading to long-term neurological impairments. Medical nutrition can be rapidly implemented in the clinic, making it a viable intervention to improve neurodevelopment after injury. The omega-3 (n-3) fatty acids docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3), uridine monophosphate (UMP) and choline have previously been shown in rodents to synergistically enhance brain phospholipids, synaptic components and cognitive performance. The objective of this study was to test the efficacy of an experimental diet containing DHA, EPA, UMP, choline, iodide, zinc, and vitamin B12 in a mouse model of perinatal HI. Male and female C57Bl/6 mice received the experimental diet or an isocaloric control diet from birth. Hypoxic ischemic encephalopathy was induced on postnatal day 9 by ligation of the right common carotid artery and systemic hypoxia. To assess the effects of the experimental diet on long-term motor and cognitive outcome, mice were subjected to a behavioral test battery. Lesion size, neuroinflammation, brain fatty acids and phospholipids were analyzed at 15 weeks after HI. The experimental diet reduced lesion size and neuroinflammation specifically in males. In both sexes, brain n-3 fatty acids were increased after receiving the experimental diet. The experimental diet also improved novel object recognition, but no significant effects on motor performance were observed. Current data indicates that early life nutritional supplementation with a combination of DHA, EPA, UMP, choline, iodide, zinc, and vitamin B12 may provide neuroprotection after perinatal HI.
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Affiliation(s)
- Myrna J. V. Brandt
- Department for Developmental Origins of Disease, University Medical Center Utrecht Brain Center and Wilhelmina Children’s Hospital, Utrecht University, 3508 AB Utrecht, The Netherlands; (M.J.V.B.); (C.H.N.)
| | - Cora H. Nijboer
- Department for Developmental Origins of Disease, University Medical Center Utrecht Brain Center and Wilhelmina Children’s Hospital, Utrecht University, 3508 AB Utrecht, The Netherlands; (M.J.V.B.); (C.H.N.)
| | - Isabell Nessel
- Centre for Neuroscience, Surgery and Trauma, Blizard Institute, Queen Mary University of London, London E1 2AD, UK; (I.N.); (T.R.M.); (A.T.M.-T.)
| | - Tatenda R. Mutshiya
- Centre for Neuroscience, Surgery and Trauma, Blizard Institute, Queen Mary University of London, London E1 2AD, UK; (I.N.); (T.R.M.); (A.T.M.-T.)
| | - Adina T. Michael-Titus
- Centre for Neuroscience, Surgery and Trauma, Blizard Institute, Queen Mary University of London, London E1 2AD, UK; (I.N.); (T.R.M.); (A.T.M.-T.)
| | | | - Lidewij Schipper
- Danone Nutricia Research, 3508 TC Utrecht, The Netherlands; (D.S.C.); (L.S.)
| | - Niek E. van der Aa
- Department of Neonatology, University Medical Center Utrecht Brain Center and Wilhelmina Children’s Hospital, Utrecht University, 3508 AB Utrecht, The Netherlands; (N.E.v.d.A.); (M.J.N.L.B.)
| | - Manon J. N. L. Benders
- Department of Neonatology, University Medical Center Utrecht Brain Center and Wilhelmina Children’s Hospital, Utrecht University, 3508 AB Utrecht, The Netherlands; (N.E.v.d.A.); (M.J.N.L.B.)
| | - Caroline G. M. de Theije
- Department for Developmental Origins of Disease, University Medical Center Utrecht Brain Center and Wilhelmina Children’s Hospital, Utrecht University, 3508 AB Utrecht, The Netherlands; (M.J.V.B.); (C.H.N.)
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Takemoto M, Kamata T, Kato D, Hara M. Controlling Surface Oxygen Concentration of a Nanocarbon Film Electrode for Improvement of Target Analytes. ANAL SCI 2020; 36:441-446. [PMID: 31787668 DOI: 10.2116/analsci.19p375] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A nanocarbon film consisting of nanocrystallites with mixed sp2 and sp3 bonds formed by unbalanced magnetron sputtering, was studied with respect to changes in the characteristics caused by the surface oxygen concentration. An electrochemical pretreatment (ECP) was conducted to change the surface oxygen concentration of the nanocarbon film. X-ray photoelectron spectroscopy (XPS) measurements revealed that nanocarbon films with different amounts of surface oxygen could be prepared. In addition, we observed no significant increase of surface roughness (Ra) at the angstrom level after ECP, owing to a stable structure containing 40% of sp3 bonds. The electrode characteristics, including the potential window, and electrochemical properties for some redox species, such as Ru(NH3)63+/2+, Fe(CN)63-/4- and some biomolecules, were investigated. The anodic potential limit became wider and ΔEp of Fe(CN)63-/4- became smaller at the treated nanocarbon film electrode than those of the as-deposited nanocarbon film electrode. Based on these results, we realized to measure uridylic acid (UMP) and inosine triphosphate (ITP) with a high oxidation potential by direct oxidation, which was difficult to measure at the as-deposited nanocarbon film electrode.
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Affiliation(s)
- Mitsunobu Takemoto
- Nitto Denko Corporation.,School of Materials and Chemical Technology, Tokyo Institute of Technology
| | - Tomoyuki Kamata
- National Institute of Advanced Industrial Science and Technology
| | - Dai Kato
- National Institute of Advanced Industrial Science and Technology
| | - Masahiko Hara
- School of Materials and Chemical Technology, Tokyo Institute of Technology
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Zhang H, Hong TY, Li G, Jiang N, Hu C, Cui X, Chu C, Zhao JL. Comparison of the Efficacy of Ultra-Mini PCNL, Flexible Ureteroscopy, and Shock Wave Lithotripsy on the Treatment of 1-2 cm Lower Pole Renal Calculi. Urol Int 2018; 102:153-159. [PMID: 30352443 DOI: 10.1159/000493508] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 09/04/2018] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To compare the efficacy of new percutaneous technique ("ultra-mini PCNL", UMP), shock wave lithotripsy (SWL) and flexible ureteroscopy (FURS) on the treatment of 1-2 cm lower pole kidney stones, and to determine the advantages and disadvantages of each method. MATERIALS AND METHODS This prospective study was based on data collected from the files of patients between March 2015 and March 2017. This study recruited a total of 180 patients with single radio-opaque lower caliceal calculi of 1-2 cm. All patients were randomly divided into 3 groups: group A was treated with UMP, group B was treated with FURS by using holmium laser and group C was treated with SWL by using the electromagnetic lithotripter. The average age, sex, size of the stone, the time of operation, the rate of no stone, the time of hospitalization, the rate of retreatment, the cost and the complications of the 3 groups were compared. The success of the operation was defined as no residual stone or < 0.3 cm on computed tomography at 3 months postoperatively. RESULTS The stone burdens of the groups were equivalent. The re-treatment rate in group C was significantly higher than that in group A and B (30 vs. 1.6%, 5%). The average operating time in group B (93.35 ± 21.64 min) was statistically significantly longer than that in group A and C (68.58 ± 15.82 min, 46.33 ± 5.81 min). Although the time of hospitalization of group A (5.32 ± 1.20 day) was longer than that of group B (3.22 ± 0.52 day) and C (1.08 ± 0.28 day; p < 0.05). The stone-free rate (SFR) in UMP, FURS, SWL were 98, 92, and 73% respectively; the highest SFR was in the UMP group (p < 0.05). The complication rates were evaluated by using the Clavien grading system, which were determined to be 16.67% in UMP, 6.67% in SWL and 8.33% in FURS. In particular, the complications of GI and GII were more common in group A (p < 0.05). CONCLUSIONS UMP, FURS, and SWL are all safe and effective in the treatment of 1-2 cm lower pole kidney stones. UMP and FURS had a better SFR than SWL, but the time of hospitalization in UMP group was longer and there were more complications in the UMP group. In addition, the operation time of FURS is longer as compared to UMP and SWL, and there is a higher rate of postoperative fever. The invasiveness and cost of SWL were lower than that of UMP and FURS, but the re-treatment rate was higher.
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Affiliation(s)
- He Zhang
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Tian Yu Hong
- Department of Urology, Shanghai Pudong New Area Gongli Hospital, Shangha, China
| | - Gang Li
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou,
| | - Ning Jiang
- Department of Urology, Shanghai Pudong New Area Gongli Hospital, Shangha, China
| | - Chuanyi Hu
- Department of Urology, Shanghai Pudong New Area Gongli Hospital, Shangha, China
| | - Xingang Cui
- Department of Urology, Shanghai Pudong New Area Gongli Hospital, Shangha, China
| | - Chuanmin Chu
- Department of Urology, Shanghai Pudong New Area Gongli Hospital, Shangha, China
| | - Jun Long Zhao
- Department of Urology, Shanghai Pudong New Area Gongli Hospital, Shangha, China
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Jones P, Elmussareh M, Aboumarzouk OM, Mucksavage P, Somani BK. Role of Minimally Invasive (Micro and Ultra-mini) PCNL for Adult Urinary Stone Disease in the Modern Era: Evidence from a Systematic Review. Curr Urol Rep 2018; 19:27. [PMID: 29516304 DOI: 10.1007/s11934-018-0764-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Purpose of Review The role of PCNL and the expertise surrounding it has expanded in recent decades. Miniaturisation of equipment and instrument size has formed a part of this innovation. Although an increasing number of studies have been performed on miniaturised PCNL (Mi-PCNL) recently, a critical appraisal on these is lacking. We therefore conducted a systematic review of the literature to evaluate the efficacy, safety and feasibility of Mi-PCNL techniques (< 15 Fr). Recent Findings A systematic review was conducted from 1990 to March 2017 on outcomes of Mi-PCNL [micro PCNL (m-PCNL) and ultra-mini PCNL (UMP)] in adult patients. Ten studies (three on m-PCNL and seven on UMP) were included in our study. Across the three studies, 118 patients (mean age 42.2 years, male to female ratio 1.3:1) underwent m-PCNL (4.8 Fr). For a mean stone size of 13.9 mm, a mean stone-free rate (SFR) was 89% and an overall complication rate was 15.2% [Clavien classification I (44%), II (28%), III (28%)], with no Clavien IV or V complications. Across the seven studies, 262 patients (mean age 49.4 years, male to female ratio 1.5:1) underwent UMP (13–14 Fr). For a mean stone size of 18.6 mm, a mean SFR was 88.3% and an overall complication rate was 6.2% [Clavien classification I (57%), II (36%), III (7%)], with no Clavien IV or V complications. While the transfusion rates for m-PCNL was 0.85%, only one case each in m-PCNL and UMP needed conversion to mini PCNL. Summary Our review shows that for small- to medium-sized renal stones, Mi-PCNL can yield good stone-free rates whilst maintaining a low morbidity associated with it. There were no Clavien > III complications and no mortality with only one transfusion reported from this minimally invasive technique.
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Liu X, Han Z, Johnson MS. The UMP Exact Test and the Confidence Interval for Person Parameters in IRT Models. Psychometrika 2018; 83:182-202. [PMID: 28836133 DOI: 10.1007/s11336-017-9580-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 03/30/2017] [Indexed: 06/07/2023]
Abstract
In educational and psychological measurement when short test forms are used, the asymptotic normality of the maximum likelihood estimator of the person parameter of item response models does not hold. As a result, hypothesis tests or confidence intervals of the person parameter based on the normal distribution are likely to be problematic. Inferences based on the exact distribution, on the other hand, do not suffer from this limitation. However, the computation involved for the exact distribution approach is often prohibitively expensive. In this paper, we propose a general framework for constructing hypothesis tests and confidence intervals for IRT models within the exponential family based on exact distribution. In addition, an efficient branch and bound algorithm for calculating the exact p value is introduced. The type-I error rate and statistical power of the proposed exact test as well as the coverage rate and the lengths of the associated confidence interval are examined through a simulation. We also demonstrate its practical use by analyzing three real data sets.
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Affiliation(s)
- Xiang Liu
- Department of Human Development, Teachers College of Columbia University, 525 West 120th Street, New York, NY, 10027-6696, USA.
| | - Zhuangzhuang Han
- Department of Human Development, Teachers College of Columbia University, 525 West 120th Street, New York, NY, 10027-6696, USA
| | - Matthew S Johnson
- Department of Human Development, Teachers College of Columbia University, 525 West 120th Street, New York, NY, 10027-6696, USA
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Cuomo F, Mosca M, Murgia S, Avino P, Ceglie A, Lopez F. Evidence for the role of hydrophobic forces on the interactions of nucleotide-monophosphates with cationic liposomes. J Colloid Interface Sci 2013; 410:146-51. [PMID: 24011561 DOI: 10.1016/j.jcis.2013.08.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 08/01/2013] [Accepted: 08/02/2013] [Indexed: 11/19/2022]
Abstract
In this work, the interaction of nucleotide-monophosphates (NMPs) with unilamellar liposomes made of 1,2-Dioleoyl-3-Trimethylammonium-Propane (DOTAP) and 1,2-Dioleoyl-sn-Glycero-3-Phosphoethanolamine (DOPE) was investigated. Here, we demonstrate how adsorption is affected by the type of nucleotide-monophosphate. Dynamic light scattering (DLS) results revealed, for each NMP, that a distinguishable concentration exists at which a significant growth of the aggregates occurs. Adenosine 5'-monophosphate (AMP) and guanosine 5'-monophosphate (GMP) have shown a higher propensity to induce liposome aggregation process and in particular GMP appears to be the most effective. From ζ-potential experiments we found that liposomes loaded with purine based nucleotides (AMP and GMP) are able to decrease the ζ-potential values to a greater extent in comparison with the pyrimidine based nucleotides thimydine 5'-monophosphate (TMP) and uridine 5'-monophosphate (UMP). Moreover, a careful analysis of nucleotide-liposome interactions revealed that nucleotides have different capacity to induce the formation of nucleotide-liposome complexes, and purine based nucleotides have higher affinities with lipid membranes. On the whole, the data emphasize that the mechanisms driving the interactions between liposomes and NMPs are also influenced by the existence of hydrophobic forces.
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Affiliation(s)
- Francesca Cuomo
- Dipartimento di Agricoltura, Ambiente Alimenti (DIAAA) and Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase (CSGI), Università degli studi del Molise, I-86100 Campobasso, Italy
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