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Grech AM, Kizirian N, Lal R, Zankl A, Birkner K, Nasir R, Muirhead R, Sau-Harvey R, Haghighi MM, Collins C, Holmes A, Skilton M, Simpson S, Gordon A. Cohort profile: the BABY1000 pilot prospective longitudinal birth cohort study based in Sydney, Australia. BMJ Open 2023; 13:e068275. [PMID: 37290940 PMCID: PMC10255277 DOI: 10.1136/bmjopen-2022-068275] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 05/23/2023] [Indexed: 06/10/2023] Open
Abstract
PURPOSE The health of parents prior to conception, a woman's health during pregnancy and the infant's environment across their first months and years collectively have profound effects on the child's health across the lifespan. Since there are very few cohort studies in early pregnancy, gaps remain in our understanding of the mechanisms underpinning these relationships, and how health may be optimised. 'BABY1000', a pilot prospective longitudinal birth cohort study, aims to (1) identify factors before and during pregnancy and early life that impact longer-term health and (2) assess the feasibility and acceptability of study design to inform future research. PARTICIPANTS Participants were based in Sydney, Australia. Women were recruited at preconception or 12 weeks' gestation, and data were collected from them throughout pregnancy and postpartum, their children until the age of 2 years, and dietary information from a partner (if able) at the last study visit. The pilot aimed to recruit 250 women. However, recruitment ceased earlier than planned secondary to limitations from the COVID-19 pandemic and the final number of subjects was 225. FINDINGS TO DATE Biosamples, clinical measurements and sociodemographic/psychosocial measures were collected using validated tools and questionnaires. Data analysis and 24-month follow-up assessments for children are ongoing. Key early findings presented include participant demographics and dietary adequacy during pregnancy. The COVID-19 pandemic and associated public health and research restrictions affected recruitment of participants, follow-up assessments and data completeness. FUTURE PLANS The BABY1000 study will provide further insight into the developmental origins of health and disease and inform design and implementation of future cohort and intervention studies in the field. Since the BABY1000 pilot was conducted across the COVID-19 pandemic, it also provides unique insight into the early impacts of the pandemic on families, which may have effects on health across the lifespan.
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Affiliation(s)
- Allison Marie Grech
- Faculty of Medicine and Health, Central Clinical School, The University of Sydney, Sydney, New South Wales, Australia
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
| | - Nathalie Kizirian
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
| | - Ravin Lal
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
| | - Angelika Zankl
- Faculty of Medicine and Health, Central Clinical School, The University of Sydney, Sydney, New South Wales, Australia
| | - Karin Birkner
- Faculty of Medicine and Health, Central Clinical School, The University of Sydney, Sydney, New South Wales, Australia
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
| | - Reeja Nasir
- Faculty of Medicine and Health, Central Clinical School, The University of Sydney, Sydney, New South Wales, Australia
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
| | - Roslyn Muirhead
- Faculty of Medicine and Health, Central Clinical School, The University of Sydney, Sydney, New South Wales, Australia
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
| | - Rachelle Sau-Harvey
- Faculty of Medicine and Health, Central Clinical School, The University of Sydney, Sydney, New South Wales, Australia
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
| | - Marjan Mosalman Haghighi
- Faculty of Medicine and Health, Central Clinical School, The University of Sydney, Sydney, New South Wales, Australia
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
| | - Clare Collins
- The University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, The University of Newcastle, New Lambton, New South Wales, Australia
| | - Andrew Holmes
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
- Faculty of Science, School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Michael Skilton
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
| | - Stephen Simpson
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
| | - Adrienne Gordon
- Faculty of Medicine and Health, Central Clinical School, The University of Sydney, Sydney, New South Wales, Australia
- The University of Sydney Charles Perkins Centre, Sydney, New South Wales, Australia
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Lloyd LK, Nasir R, Nicholson C, Strange G, Celermajer DS. Obstacles in establishing a national disease registry in Australia: lessons from the development of the CHAANZ Congenital Heart Disease Registry. AUST HEALTH REV 2023:AH23063. [PMID: 37188545 DOI: 10.1071/ah23063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 04/26/2023] [Indexed: 05/17/2023]
Abstract
ObjectivesTo provide insights into the obstacles which pose challenges to the set-up of any National Registry in Australia.MethodsAn analysis of our experience in executing a Multi-Institutional Agreement (MIA) and obtaining ethics and governance approvals, post-award of a large Medical Research Futures Fund grant in June 2020.ResultsFrom July 2020, our timeline to an executed MIA was 283 days, despite full-time staff working towards this goal. Subsequently, after lead site ethics approval, time to site governance approvals ranged from 9 to 291 days. A total of 214 emails were sent during the MIA development and signing. There were 11-71 emails sent to individual governance offices and the number of requested points of additional information ranged from 0 to 31 queries.ConclusionsThere were considerable time delays in executing the initial (pre-research) stages of a National Federal Government funded Registry project which required substantial time and resources. We report a wide variation in requirements between different states and institutions. We propose several strategies which could be implemented to facilitate a more streamlined approach to research ethics and governance. This centralised approach would allow for better use of funding and facilitate better progress in medical research.
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Ahmad Y, Asad N, Nasir R, Ahmed O. Abstract No. 523 Geospatial and Socioeconomic Disparities in Access to Interventional Radiology Care in the United States. J Vasc Interv Radiol 2023. [DOI: 10.1016/j.jvir.2022.12.381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023] Open
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Sabiha-Javied, Siddque N, Waheed S, uz Zaman Q, Aslam A, Tufail M, Nasir R. Uptake of heavy metal in wheat from application of different phosphorus fertilizers. J Food Compost Anal 2023. [DOI: 10.1016/j.jfca.2022.104958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Liang S, Nasir R, Skilton M, Toniutti C, Bell-Anderson K, O'Leary F. Biomarkers of Dietary Patterns: A Systematic Review of Randomised Controlled Trials. Curr Dev Nutr 2021. [DOI: 10.1093/cdn/nzab048_013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Objectives
We undertook a systematic review of clinical trials to identify a) dietary biomarkers being used to assess dietary pattern compliance, and b) novel biomarkers that are affected by intake of distinct dietary patterns.
Methods
The search strategy was developed in Medline and adapted for four additional databases: EMBASE, Cochrane CENTRAL, PreMedline, and CINAHL. Two independent reviewers extracted data and assessed risk of bias using the Cochrane tool.
Results
Literature search retrieved 3930 records; 450 full texts were assessed, and 30 articles reporting randomised controlled trials met the inclusion criteria. The most studied dietary patterns were the Mediterranean diet, healthy Nordic diet, Dietary Approaches to Stop Hypertension (DASH) diet, followed by low glycaemic-load diet, vegetarian diet, diets based on national and international guidelines (i.e., United Kingdom and World Health Organization Eating Guidelines), Korean diet and prudent diet. Of these, 13 articles incorporated prospectively identified dietary biomarkers, the most common being omega-3 index from erythrocytes or whole blood, 24-h urinary electrolytes, and serum or plasma carotenoids. Seventeen articles identified novel metabolomic biomarkers associated with dietary patterns, the most frequently identified being those associated with protein, lipid, and fish intakes.
Conclusions
Using dietary biomarkers of single nutrients, individual foods and food groups is commonly used to assess dietary compliance to dietary pattern interventions in controlled settings. However, identifying an individual's specific or broad dietary pattern, based on their biomarker profile, remains an area for future research. A framework that incorporates multiple biomarkers of individual dietary characteristics is likely necessary to accurately capture the complexity of dietary patterns.
Funding Sources
N/A.
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Affiliation(s)
- Shuang Liang
- Boden Collaboration for Obesity, Nutrition, Exercise and Eating Disorders
| | - Reeja Nasir
- Boden Collaboration for Obesity, Nutrition, Exercise and Eating Disorders
| | - Michael Skilton
- Boden Collaboration for Obesity, Nutrition, Exercise and Eating Disorders
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Mckenzie KM, Nasir R, Kong Y, Dissanayake HU, McMullan R, Gordon A, Meroni A, Phang M, Skilton MR. Maternal Dietary Carbohydrate Intake and Newborn Aortic Wall Thickness. Nutrients 2021; 13:1382. [PMID: 33924014 PMCID: PMC8073292 DOI: 10.3390/nu13041382] [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] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 04/02/2021] [Accepted: 04/15/2021] [Indexed: 11/16/2022] Open
Abstract
Evidence from animal models indicates that maternal diet during pregnancy affects offspring cardiometabolic health. Improving carbohydrate quality during high-risk pregnancies reduces aortic intima-medial thickness; a marker for early atherosclerosis; in the infant offspring. We sought to determine whether maternal carbohydrate quantity and quality are associated with newborn aortic intima-medial thickness in healthy pregnancies. Maternal diet throughout pregnancy was evaluated in 139 mother-child dyads using a validated food frequency questionnaire. Carbohydrate intake was expressed as quantity (% total energy), quality (fibre, glycaemic index), and glycaemic burden (glycaemic load). Aortic intima-medial thickness was measured by high-frequency ultrasound of the neonatal abdominal aorta. Neither quantity nor quality of maternal carbohydrate intake during pregnancy was associated with meaningful differences in offspring maximum aortic intima-medial thickness with the exception of fibre intake in women with overweight or obesity which was inversely associated (-8 μm [95% CI -14, -1] per g fibre, p = 0.04). In healthy pregnancy, the quantity and quality of maternal carbohydrate intake is likely not a meaningful modifiable lifestyle factor for influencing offspring vascular health. The effect of carbohydrate quality may only be evident in high-risk pregnancies, consistent with previous findings. These findings may be confirmed in prospective dietary trials in pregnancy.
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Affiliation(s)
- Kirsty M. Mckenzie
- Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia; (K.M.M.); (R.N.); (Y.K.); (H.U.D.); (R.M.); (A.M.); (M.P.)
- Sydney Medical School, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia;
| | - Reeja Nasir
- Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia; (K.M.M.); (R.N.); (Y.K.); (H.U.D.); (R.M.); (A.M.); (M.P.)
- Sydney Medical School, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia;
| | - Yang Kong
- Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia; (K.M.M.); (R.N.); (Y.K.); (H.U.D.); (R.M.); (A.M.); (M.P.)
- Sydney Medical School, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia;
| | - Hasthi U. Dissanayake
- Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia; (K.M.M.); (R.N.); (Y.K.); (H.U.D.); (R.M.); (A.M.); (M.P.)
- Sydney Medical School, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia;
| | - Rowena McMullan
- Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia; (K.M.M.); (R.N.); (Y.K.); (H.U.D.); (R.M.); (A.M.); (M.P.)
- Sydney Medical School, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia;
- Royal Prince Alfred Hospital, Missenden Road, Camperdown, NSW 2050, Australia
| | - Adrienne Gordon
- Sydney Medical School, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia;
- Royal Prince Alfred Hospital, Missenden Road, Camperdown, NSW 2050, Australia
- Sydney Institute for Women, Children and their Families, Sydney Local Health District, Sydney, NSW 2000, Australia
| | - Alice Meroni
- Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia; (K.M.M.); (R.N.); (Y.K.); (H.U.D.); (R.M.); (A.M.); (M.P.)
| | - Melinda Phang
- Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia; (K.M.M.); (R.N.); (Y.K.); (H.U.D.); (R.M.); (A.M.); (M.P.)
| | - Michael R. Skilton
- Boden Collaboration for Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia; (K.M.M.); (R.N.); (Y.K.); (H.U.D.); (R.M.); (A.M.); (M.P.)
- Sydney Medical School, Charles Perkins Centre, University of Sydney, Camperdown, NSW 2006, Australia;
- Sydney Institute for Women, Children and their Families, Sydney Local Health District, Sydney, NSW 2000, Australia
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Smith DS, Nasir R, Parker W, Peters A, Merrington G, van Egmond R, Lofts S. Developing understanding of the fate and behaviour of silver in fresh waters and waste waters. Sci Total Environ 2021; 757:143648. [PMID: 33316521 DOI: 10.1016/j.scitotenv.2020.143648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 11/03/2020] [Accepted: 11/03/2020] [Indexed: 06/12/2023]
Abstract
The Windermere Humic Aqueous Model (WHAM) is often used for risk assessment of metals; WHAM can be used to estimate the potential bioavailability of dissolved metals, where metals complexed to dissolved organic matter (DOM) are expected to be less toxic than ionic forms. Silver is a potential metal of concern but WHAM has not been rigorously tested against experimental measurements. This study compares WHAM predictions to measured ionic silver during fixed pH (4, 8 or 10) argentometric titrations of DOM from diverse origins. There were almost two orders of magnitude variation in free silver between sources but, within model uncertainty, WHAM captured this variability. This agreement, between measurements and models, suggests that WHAM is an appropriate tool for silver risk assessment in surface receiving waters when DOM is predominantly in the form of humic/fulvic acids. In sewage samples WHAM dramatically underestimated silver binding by approximately 3 orders of magnitude. Simulations with additional specific strong silver binding sulphide-like binding sites could explain Ag binding at low loadings, but not at higher loadings. This suggests the presence of additional intermediate strength binding sites. These additional ligands would represent components of the raw sewage largely absent in natural waters unimpacted by sewage effluents. A revised empirical model was proposed to account for these sewage-specific binding sites. Further, it is suspected that as sewage organic matter is degraded, either by natural attenuation or by engineered treatment, that sewage organic matter will degrade to a form more readily modelled by WHAM; i.e., humic-like substances. These ageing experiments were performed starting from raw sewage, and the material did in fact become more humic-like, but even after 30 days of aerobic incubation still showed greater Ag+ binding than WHAM predictions. In these incubation experiments it was found that silver (up to 1000 μg/L) had minimal impact on ammonia oxidation kinetics.
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Affiliation(s)
- D Scott Smith
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, Canada.
| | - R Nasir
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Wayne Parker
- Department of Civil and Environmental Engineering, University of Waterloo, Waterloo, ON, Canada
| | - A Peters
- WCA Environment Ltd., Brunel House, Faringdon, Oxfordshire, United Kingdom
| | - G Merrington
- WCA Environment Ltd., Brunel House, Faringdon, Oxfordshire, United Kingdom
| | - R van Egmond
- Safety and Environmental Assurance Centre, Unilever, Sharnbrook, Bedfordshire, United Kingdom
| | - S Lofts
- Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, United Kingdom
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Nasir R, Cai TY, Meroni A, Skilton M. P.32 Non-Invasive Measures of Arteriosclerosis Across Childhood and Adolescence: Insights Into the Natural History of Disease. Artery Res 2020. [DOI: 10.2991/artres.k.201209.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Rafique S, Khan S, Bashir S, Nasir R. Facile development of highly sensitive femtomolar electrochemical DNA biosensor using gold nanoneedle-modified electrode. Chem Pap 2019. [DOI: 10.1007/s11696-019-00874-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Ahmad NNR, Mukhtar H, Mohshim DF, Nasir R, Man Z. Corrigendum: Effect of different organic amino cations on SAPO-34 for PES/SAPO-34 mixed matrix membranes toward CO 2
/CH 4
separation. J Appl Polym Sci 2017. [DOI: 10.1002/app.45130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Ahmad NNR, Mukhtar H, Mohshim DF, Nasir R, Man Z. Effect of different organic amino cations on SAPO-34 for PES/SAPO-34 mixed matrix membranes toward CO2/CH4separation. J Appl Polym Sci 2016. [DOI: 10.1002/app.43387] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- N. N. R. Ahmad
- Department of Chemical Engineering; Universiti Teknologi PETRONAS; Perak Darul Ridzuan Malaysia
| | - H. Mukhtar
- Department of Chemical Engineering; Universiti Teknologi PETRONAS; Perak Darul Ridzuan Malaysia
| | - D. F. Mohshim
- Department of Chemical Engineering; Universiti Teknologi PETRONAS; Perak Darul Ridzuan Malaysia
| | - R. Nasir
- Department of Chemical Engineering; Universiti Teknologi PETRONAS; Perak Darul Ridzuan Malaysia
| | - Z. Man
- Department of Chemical Engineering; Universiti Teknologi PETRONAS; Perak Darul Ridzuan Malaysia
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Nasir R, Mukhtar H, Man Z. Fabrication, Characterization and Performance Study of N-methyl-diethanolamine
(MDEA)-Polyethersulfone (PES) Amine Polymeric Membrane for CO2/CH4 Separation. ACTA ACUST UNITED AC 2014. [DOI: 10.3923/jas.2014.1186.1191] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Mannan HA, Mukhtar H, Murugesan T, Nasir R, Mohshim DF, Mushtaq A. Recent Applications of Polymer Blends in Gas Separation Membranes. Chem Eng Technol 2013. [DOI: 10.1002/ceat.201300342] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Nasir R, Sabeeh K. Magnetothermoelectric transport in modulated and unmodulated graphene. J Phys Condens Matter 2011; 23:375301. [PMID: 21881170 DOI: 10.1088/0953-8984/23/37/375301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We draw motivation from recent experimental studies and present a comprehensive study of magnetothermoelectric transport in a graphene monolayer within the linear response regime. We employ the modified Kubo formalism developed for thermal transport in a magnetic field. Thermopower as well as thermal conductivity as a function of the gate voltage of a graphene monolayer in the presence of a magnetic field perpendicular to the graphene plane is determined for low magnetic fields (∼1 T) as well as high fields (∼8 T). We include the effects of screened charged impurities on thermal transport. We find good qualitative and quantitative agreement with recent experimental work on the subject. In addition, in order to analyze the effects of modulation, which can be induced by various means, on the thermal transport in graphene, we evaluate the thermal transport coefficients for a graphene monolayer subjected to a periodic electric modulation in a magnetic field. The results are presented as a function of the magnetic field and the gate voltage.
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Affiliation(s)
- R Nasir
- Department of Physics, Quaid-i-Azam University, Islamabad, Pakistan
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Nasir R, Khan MA, Tahir M, Sabeeh K. Thermodynamic properties of a weakly modulated graphene monolayer in a magnetic field. J Phys Condens Matter 2010; 22:025503. [PMID: 21386257 DOI: 10.1088/0953-8984/22/2/025503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Theoretical investigation of thermodynamic properties of an electrically modulated graphene monolayer in the presence of a perpendicular magnetic field B is presented. This work is aimed at determining the modulation-induced effects on the thermodynamic properties of graphene. The results obtained are compared with those of conventional two-dimensional electron gas (2DEG) systems realized in semiconductor heterostructures. The one-dimensional periodic potential, due to electric modulation lifts the degeneracy of the Landau levels and converts them into bands whose width oscillates as a function of B. We find commensurability (Weiss) oscillations for small values of B and de Haas-van Alphen (dHvA)-type oscillations at larger values of B. We find that the modulation-induced effects on the thermodynamic properties are enhanced and less damped with temperature in graphene compared with conventional 2DEG systems. Furthermore, we have derived analytic asymptotic expressions which allow us to determine the critical temperature and critical magnetic field for the damping of magnetic oscillations in the thermodynamic quantities considered here.
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Affiliation(s)
- R Nasir
- Department of Physics, Quaid-i-Azam University, Islamabad 45320, Pakistan
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Miller DT, Shen Y, Weiss LA, Korn J, Anselm I, Bridgemohan C, Cox GF, Dickinson H, Gentile J, Harris DJ, Hegde V, Hundley R, Khwaja O, Kothare S, Luedke C, Nasir R, Poduri A, Prasad K, Raffalli P, Reinhard A, Smith SE, Sobeih MM, Soul JS, Stoler J, Takeoka M, Tan WH, Thakuria J, Wolff R, Yusupov R, Gusella JF, Daly MJ, Wu BL. Microdeletion/duplication at 15q13.2q13.3 among individuals with features of autism and other neuropsychiatric disorders. J Med Genet 2008; 46:242-8. [PMID: 18805830 DOI: 10.1136/jmg.2008.059907] [Citation(s) in RCA: 249] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Segmental duplications at breakpoints (BP4-BP5) of chromosome 15q13.2q13.3 mediate a recurrent genomic imbalance syndrome associated with mental retardation, epilepsy, and/or electroencephalogram (EEG) abnormalities. PATIENTS DNA samples from 1445 unrelated patients submitted consecutively for clinical array comparative genomic hybridisation (CGH) testing at Children's Hospital Boston and DNA samples from 1441 individuals with autism from 751 families in the Autism Genetic Resource Exchange (AGRE) repository. RESULTS We report the clinical features of five patients with a BP4-BP5 deletion, three with a BP4-BP5 duplication, and two with an overlapping but smaller duplication identified by whole genome high resolution oligonucleotide array CGH. These BP4-BP5 deletion cases exhibit minor dysmorphic features, significant expressive language deficits, and a spectrum of neuropsychiatric impairments that include autism spectrum disorder, attention deficit hyperactivity disorder, anxiety disorder, and mood disorder. Cognitive impairment varied from moderate mental retardation to normal IQ with learning disability. BP4-BP5 covers approximately 1.5 Mb (chr15:28.719-30.298 Mb) and includes six reference genes and 1 miRNA gene, while the smaller duplications cover approximately 500 kb (chr15:28.902-29.404 Mb) and contain three reference genes and one miRNA gene. The BP4-BP5 deletion and duplication events span CHRNA7, a candidate gene for seizures. However, none of these individuals reported here have epilepsy, although two have an abnormal EEG. CONCLUSIONS The phenotype of chromosome 15q13.2q13.3 BP4-BP5 microdeletion/duplication syndrome may include features of autism spectrum disorder, a variety of neuropsychiatric disorders, and cognitive impairment. Recognition of this broader phenotype has implications for clinical diagnostic testing and efforts to understand the underlying aetiology of this syndrome.
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Affiliation(s)
- D T Miller
- Department of Laboratory Medicine, Children's Hospital Boston, 300 Longwood Ave, Boston, Massachusetts 02115, USA
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Nasir R, Mohd. Nor N, Yaacob N. Differential expression of PPARgamma1 and gamma2, and ERalpha in MCF-7 and MDA-MB-231 breast cancer cell lines. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)71747-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Ding J, Shen M, Nasir R, Dmowski W. Morphological criteria of frozen-thawed blastocysts are good predictors for successful frozen blastocyst transfer cycles. Fertil Steril 2004. [DOI: 10.1016/j.fertnstert.2004.07.377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Köchling J, Pistor G, Märzhäuser Brands S, Nasir R, Lanksch WR. The Currarino syndrome--hereditary transmitted syndrome of anorectal, sacral and presacral anomalies. Case report and review of the literature. Eur J Pediatr Surg 1996; 6:114-9. [PMID: 8740138 DOI: 10.1055/s-2008-1066487] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The Currarino triad is a hereditary transmitted syndrome, originally defined by Currarino as ASP-association, consisting of an anorectal malformation, a sacral bony defect and a presacral mass. In most cases autosomal dominant transmission is suggested. In family members one or two features of the syndrome may be missing, indicating an incomplete form of this complex. We describe two unrelated girls at the age of 8 and 9 months respectively with ASP-association. Family screening in both patients showed 8 additional cases with a complete or incomplete Currarino triad, four of them being asymptomatic. A review of the literature up to 1991 revealed 48 patients with ASP-association. In more than 80% of cases, this complex is diagnosed in the first decade, whereas incomplete Currarino syndrome is diagnosed predominantly in adults. Most frequently the presacral mass in ASP-association was reported to be an anterior meningocele (47%) and a benign teratoma (40%). The number of patients with Currarino syndrome has been underestimated so far. We recommend anorectal examination, pelvic ultrasound and pelvic x-rays in all patients with a history of chronic constipation since early childhood. Positive findings should lead to further investigations such as barium enema, MRI, myelography and family screening. Close cooperation between pediatric surgeons and neurosurgeons is required to ensure adequate surgical treatment, considering both the risk of malignant degeneration as well as the risk of intraoperative nerve damage. Thus, radical excisional surgery is not obligatory in every case of Currarino syndrome.
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Affiliation(s)
- J Köchling
- Department of Pediatric Surgery, University Hospital Rudolf Virchow Berlin, Freie Universität Berlin, Germany
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22
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Abstract
PURPOSE A retrospective study was carried out in order to determine the role of sonography in establishing the diagnosis in extremity osteomyelitis. MATERIALS AND METHODS The imaging documents of 24 infants and children aged from 2 weeks to 13 years with osteomyelitis (acute 21, chronic 3) were reviewed. Sonograms and conventional radiographs were available in all patients. Additional skeletal scintigraphy had been performed in 13 patients and MRI in only 3. Special emphasis was put on the different ultrasound findings and their onset in the course of disease. RESULTS Intra-articular fluid collections (in 15 cases) and/or subperiosteal abscess formation (in 12) were the most frequent early sonographic findings, and preceded any radiographic changes by several days in 11 of these cases. Together with positive clinical signs of inflammation, they were usually sufficient to establish the correct diagnosis. In selected cases, fluid or abscess puncture for immediate microscopic and later bacteriological studies was carried out under sonographic control. In addition, sonography was also able to detect superficial cortical erosion and even an intramedullary focus in a very young patient. CONCLUSION Ultrasonography is a very helpful tool for establishing the correct diagnosis in osteomyelitis and reducing the frequency of additional imaging studies.
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Affiliation(s)
- T W Riebel
- Department of Pediatric Radiology, Virchow Clinic, Humboldt University, Reinickendorfer Strasse 61, D-13347 Berlin, Germany
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23
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Abstract
With regard to injuries of the extremities caused by birth trauma, ultrasound allows simultaneous direct evaluation of the surface of osseous elements and of cartilaginous and soft-tissue structures as well. Thus, not only fractures, but also concomitant articular fluid collections, respectively haematomas and/or dislocation of an epiphysis are demonstrated in their initial extent and in their course of healing. Additionally, closed repositions, for instance of a displaced epiphysis, can be exactly monitored by ultrasound. A reduced number of roentgenograms as well as renunciation of other imaging modalities are the consequence. Own experiences in 4 patients with birth trauma to the humerus confirm the high validity of ultrasound in this area as well.
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Affiliation(s)
- T Riebel
- Universitätsklinikum Rudolf Virchow, Wedding
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24
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Bassir C, Riebet T, Nasir R, Kaufmann HJ. Long-term experience in using iotrolan for paediatric gastrointestinal studies. Eur Radiol 1994. [DOI: 10.1007/bf00599073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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25
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Abstract
Over a period of 3 3/4 years, hydrostatic reduction of ileocolic intussusception was performed under sonographic guidance in 47 cases (a total of 41 consecutive patients). The enema consisted of a mixture of isotonic electrolyte solution and water-soluble contrast medium (9:1 ratio) and was given at a hydrostatic pressure of 80-100 cm water. Reduction was successful in 83% of cases (n = 39). Even initially remaining ileo-ileal intussusception could finally be reduced in two cases. No complications were observed. Since, in comparison with other conservative methods of reduction, the success rate was not substantially worse (versus that of pneumatic reduction) or was even higher (versus that of barium enema reduction), the method described can be recommended for wider use because of the substantial reduction in radiation exposure.
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Affiliation(s)
- T W Riebel
- Department of Pediatric Radiology, University Clinic Rudolf Virchow-Wedding, Free University, Berlin, Germany
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26
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Abstract
Cerebral ultrasound (US) imaging was performed as a screening procedure in approximately 3,600 neonates and infants over a period of 18 months. Hyperechoic lesions in the basal ganglia and thalamic region were detected incidentally in 15 of these patients. Clinical diagnoses included cytomegalovirus infection, asphyxia, rotavirus infection, prematurity, amniotic infection, dysmorphic stigmata, hyperbilirubinemia, congenital heart disease, and diabetic fetopathia. Lesions showed a single punctate (n = 5), multiple punctate (n = 8), or stripe-like pattern (n = 2), with no disease-specific distribution. Computed tomography performed in two of the 15 patients was normal. Lesions resolved within four to seven months in four of eleven cases who had follow-up studies, whereas echogenicities persisted in the remaining seven patients over a period of observation ranging between one to 15 months. Our results indicate that hyperechoic lesions in the basal ganglia and thalamic region may be associated with congenital infections and asphyxia, but could indicate some other unknown pathology. No correlation was found between the morphology of foci and both clinical diagnosis and results of follow-up studies.
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Affiliation(s)
- K Weber
- Department of Pediatric Radiology, Klinikum Rudolf Virchow, Standort Wedding, Freie Universität Berlin, FRG
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27
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Abstract
Within a period of 2.5 years, cystic structures in the choroid plexus were encountered at cerebral sonography in 70 neonates and babies (45 male, 25 female; 18 premature babies). Their prevalence in patients examined during the first 4 weeks of life (n = 55) was 3%. The size of the cysts ranged from 1-4 and, rarely, up to 7 mm. They were mostly solitary and unilateral. Follow-up sonograms over periods up to 13 months showed that most of the cysts persisted unchanged. A few disappeared (n = 7), while distinct increase in size was observed in 1 case. Since no additional sonographic changes were observed and none of the patients displayed any neurological abnormalities and no association existed with any other, particularly chromosomal, disease, such plexus cysts are postulated to represent a normal sonographic finding and do not require follow-up.
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Affiliation(s)
- T Riebel
- Department of Paediatric Radiology, University Clinic Rudolf Virchow (Wedding), Free University, Berlin, FRG
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28
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Riebel T, Nasir R, Käding M, Eckart L. [Deterioration of clinical findings in hip joint follow-ups in neonatal screening]. Monatsschr Kinderheilkd 1990; 138:664-9. [PMID: 2079942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
6 per cent out of 4290 hips checked by neonatal ultrasound screening could be reexamined later on. 7 of 200 hips (i.e. 4 per cent), primarily categorized as type IIa, showed an unexpected severe deterioration to type D (n = 3) or even to type IIIa (n = 4) after a mean-time of 9 weeks. Additional 5 cases with similar unfavourable courses from IIa to IIc, D or IIIa, and even 3 initially normal hips, changing to type IIa, were seen in another screening material (not yet systematically analyzed). Reasons for possible initial misinterpretation (purely visual evaluation in most cases, uncertainties in measuring suboptimal sonographic cuts, deficiencies in technical equipment and documentation), equivocal classification of border-line sonograms as well as possible influence of additional risk factors are discussed. Routine sonographic re-examinations after 6 (to 12) weeks are recommended as obligatory for all hips.
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Affiliation(s)
- T Riebel
- Bereich Pädiatrische Radiologie, Universitätsklinikum Rudolf Virchow, Standort Wedding, Freie Universität Berlin
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