1
|
Tang PC, Chan MK, Chung JY, Chan AS, Zhang D, Li C, Leung K, Ng CS, Wu Y, To K, Lan H, Tang PM. Hematopoietic Transcription Factor RUNX1 is Essential for Promoting Macrophage-Myofibroblast Transition in Non-Small-Cell Lung Carcinoma. Adv Sci (Weinh) 2024; 11:e2302203. [PMID: 37967345 PMCID: PMC10767400 DOI: 10.1002/advs.202302203] [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] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 10/06/2023] [Indexed: 11/17/2023]
Abstract
Macrophage-myofibroblast transition (MMT) is a newly discovered pathway for mass production of pro-tumoral cancer-associated fibroblasts (CAFs) in non-small cell lung carcinoma (NSCLC) in a TGF-β1/Smad3 dependent manner. Better understanding its regulatory signaling in tumor microenvironment (TME) may identify druggable target for the development of precision medicine. Here, by dissecting the transcriptome dynamics of tumor-associated macrophage at single-cell resolution, a crucial role of a hematopoietic transcription factor Runx1 in MMT formation is revealed. Surprisingly, integrative bioinformatic analysis uncovers Runx1 as a key regulator in the downstream of MMT-specific TGF-β1/Smad3 signaling. Stromal Runx1 level positively correlates with the MMT-derived CAF abundance and mortality in NSCLC patients. Mechanistically, macrophage-specific Runx1 promotes the transcription of genes related to CAF signatures in MMT cells at genomic level. Importantly, macrophage-specific genetic deletion and systemic pharmacological inhibition of TGF-β1/Smad3/Runx1 signaling effectively prevent MMT-driven CAF and tumor formation in vitro and in vivo, representing a potential therapeutic target for clinical NSCLC.
Collapse
Affiliation(s)
- Philip Chiu‐Tsun Tang
- Department of Anatomical and Cellular PathologyState Key Laboratory of Translational OncologyThe Chinese University of Hong KongShatin999077Hong Kong
| | - Max Kam‐Kwan Chan
- Department of Anatomical and Cellular PathologyState Key Laboratory of Translational OncologyThe Chinese University of Hong KongShatin999077Hong Kong
| | - Jeff Yat‐Fai Chung
- Department of Anatomical and Cellular PathologyState Key Laboratory of Translational OncologyThe Chinese University of Hong KongShatin999077Hong Kong
| | - Alex Siu‐Wing Chan
- Department of Applied Social SciencesThe Hong Kong Polytechnic UniversityHunghom999077Hong Kong
| | - Dongmei Zhang
- College of PharmacyJinan UniversityGuangzhou510632China
| | - Chunjie Li
- Department of Head and Neck OncologyWest China Hospital of StomatologySichuan UniversityChengduSichuan610041China
| | - Kam‐Tong Leung
- Department of PaediatricsThe Chinese University of Hong KongShatin999077Hong Kong
| | - Calvin Sze‐Hang Ng
- Department of SurgeryThe Chinese University of Hong KongShatin999077Hong Kong
| | - Yi Wu
- MOE Key Laboratory of Environment and Genes Related to DiseasesSchool of Basic Medical SciencesXi'an Jiaotong UniversityXi'an710061China
| | - Ka‐Fai To
- Department of Anatomical and Cellular PathologyState Key Laboratory of Translational OncologyThe Chinese University of Hong KongShatin999077Hong Kong
| | - Hui‐Yao Lan
- Department of Medicine and TherapeuticsLi Ka Shing Institute of Health SciencesThe Chinese University of Hong KongShatin999077Hong Kong
| | - Patrick Ming‐Kuen Tang
- Department of Anatomical and Cellular PathologyState Key Laboratory of Translational OncologyThe Chinese University of Hong KongShatin999077Hong Kong
| |
Collapse
|
2
|
Harrison N, Chan MK. Harrison and Chan Reply. Phys Rev Lett 2023; 130:199702. [PMID: 37243646 DOI: 10.1103/physrevlett.130.199702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 04/06/2023] [Indexed: 05/29/2023]
Affiliation(s)
- N Harrison
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - M K Chan
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| |
Collapse
|
3
|
Harrison N, Chan MK. Magic Gap Ratio for Optimally Robust Fermionic Condensation and Its Implications for High-T_{c} Superconductivity. Phys Rev Lett 2022; 129:017001. [PMID: 35841553 DOI: 10.1103/physrevlett.129.017001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 03/22/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
Bardeen-Schrieffer-Cooper (BCS) and Bose-Einstein condensation (BEC) occur at opposite limits of a continuum of pairing interaction strength between fermions. A crossover between these limits is readily observed in a cold atomic Fermi gas. Whether it occurs in other systems such as the high temperature superconducting cuprates has remained an open question. We uncover here unambiguous evidence for a BCS-BEC crossover in the cuprates by identifying a universal magic gap ratio 2Δ/k_{B}T_{c}≈6.5 (where Δ is the pairing gap and T_{c} is the transition temperature) at which paired fermion condensates become optimally robust. At this gap ratio, corresponding to the unitary point in a cold atomic Fermi gas, the measured condensate fraction N_{0} and the height of the jump δγ(T_{c}) in the coefficient γ of the fermionic specific heat at T_{c} are strongly peaked. In the cuprates, δγ(T_{c}) is peaked at this gap ratio when Δ corresponds to the antinodal spectroscopic gap, thus reinforcing its interpretation as the pairing gap. We find the peak in δγ(T_{c}) also to coincide with a normal state maximum in γ, which is indicative of a pairing fluctuation pseudogap above T_{c}.
Collapse
Affiliation(s)
- N Harrison
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - M K Chan
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| |
Collapse
|
4
|
Chan MK, Jull P. Accuracy of selected neurological clinical tests in diagnosing MRI-detectable forebrain lesion in dogs. Aust Vet J 2020; 98:499-503. [PMID: 32671818 DOI: 10.1111/avj.12997] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 06/05/2020] [Accepted: 06/22/2020] [Indexed: 01/23/2023]
Abstract
This retrospective case study aims to evaluate the accuracy of menace response, response to nasal stimulation and proprioceptive placing in diagnosing forebrain lesion in dogs. A total of 145 client-owned dogs investigated by magnetic resonance imaging study of the brain between December 2017 and June 2019 were evaluated. Seventy-one dogs with no magnetic resonance imaging-detectable intracranial and significant cerebrospinal fluid abnormality or recent history of seizure (<48 h) served as controls. Binary regression analysis was performed to determine the sensitivity, specificity and likelihood ratios of each selected test. Older age at presentation was a significant risk factor for the presence of a forebrain lesion. Menace (62.5%) and proprioceptive deficits (40.5%) were common findings in all dogs. They were also significantly associated with the presence of forebrain abnormality. Moreover, they were more sensitive (77.3% and 82.2%, respectively) and specific (50.0% and 62.5%, respectively) when applied to dogs aged 6 years or older. Nonetheless, all of these tests' likelihood ratios, and thus reliability are poor. These neurological tests are commonly employed for diagnosing forebrain disease in dogs, yet are not highly accurate in diagnosing forebrain abnormality. Clinicians should interpret these clinical test results along with the patient history when designing a diagnostic plan.
Collapse
Affiliation(s)
- M K Chan
- The VSCAN, Ottawa, Ontario, Canada
| | - P Jull
- The VSCAN, Ottawa, Ontario, Canada
| |
Collapse
|
5
|
Chan MK, Toribio JA, Podadera JM, Child G. Incidence, cause, outcome and possible risk factors associated with facial nerve paralysis in dogs in a Sydney population (2001-2016): a retrospective study. Aust Vet J 2019; 98:140-147. [PMID: 31867719 DOI: 10.1111/avj.12906] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [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: 11/13/2018] [Revised: 11/10/2019] [Accepted: 11/15/2019] [Indexed: 12/01/2022]
Abstract
OBJECTIVE This study aims to assess the incidence and causes of facial nerve paralysis (FNP) in dogs in the Sydney region. Its outcome and possible risk factors are investigated to prognosticate and aid design of diagnostic and treatment plans. DESIGN Retrospective case study. METHODS Client-owned dogs presented to the University Veterinary Teaching Hospital, Sydney (UVTHS), between 2001 and 2016 with FNP were included (n = 122). The incidence of each cause of FNP was investigated. A reference population of noncases seen at the UVTHS during the same time period was used to study the association between idiopathic facial nerve paralysis (IFNP) and gender, age and breed. RESULTS IFNP (29.5%) was the most common diagnosis. Male dogs (odds ratio [OR], 2.3) had increased odds of IFNP compared with female dogs. Age was a significant risk factor for both the occurrence of FNP and IFNP. There was higher occurrence of IFNP among middle-aged dogs (5-13 years) and reduced risk in juvenile dogs (less than 2 years). Cavalier King Charles Spaniels were over-represented for FNP (OR, 6.9) and IFNP (OR, 17.5). For IFNP, 6 of 16 dogs with known follow-up showed definitive resolution within 3 years of diagnosis. Concurrent vestibular signs were common in dogs with middle/inner ear abnormality and intracranial disease; and were also seen in 50% of dogs with IFNP. CONCLUSION The results of this study demonstrate statistical predilections in age, gender and breed for IFNP. Guarded prognosis for recovery should be given to dogs diagnosed with IFNP and supportive management instigated.
Collapse
Affiliation(s)
- M K Chan
- Sydney School of Veterinary Science, The University of Sydney, New South Wales, Australia
| | - J-Alml Toribio
- Sydney School of Veterinary Science, The University of Sydney, New South Wales, Australia
| | - J M Podadera
- Sydney School of Veterinary Science, The University of Sydney, New South Wales, Australia
| | - G Child
- Sydney School of Veterinary Science, The University of Sydney, New South Wales, Australia
| |
Collapse
|
6
|
Tsang KH, Chan WSW, Shiu CK, Lee JCY, Chan MK. Magnetic Resonance Imaging of Hypertrophic Cardiomyopathy. Hong Kong J Radiol 2018. [DOI: 10.12809/hkjr1815336] [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: 11/05/2022] Open
|
7
|
Lee JCY, Tsang KH, Cheuk W, Chan MK. Positron-emission Tomography–Computed Tomography for Detection of Primary Pericardial Lymphoma. Hong Kong J Radiol 2018. [DOI: 10.12809/hkjr1616405] [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: 11/05/2022] Open
|
8
|
Fung HS, Chiu JLF, Shu SJ, Chan MK, Lai AKH, Wong WK, Chan SCH. A Man with Head Injury. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490790801500208] [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] [Indexed: 11/16/2022] Open
Abstract
Head injury is common and can be associated with significant morbidity and mortality. We report a 71-year-old man with typical imaging findings of depressed skull fracture on plain film and computed tomography with images in multi-planar reformat and 3-dimensional volume rendering technique, followed by a brief review of the literature.
Collapse
|
9
|
Chan CYH, Tsang KWK, Lai KC, Chan MK. Dual-energy Computed Tomography for Diagnosis of Gouty Tophus of Tibia with Pathological Fracture Simulating Malignancy. Hong Kong J Radiol 2017. [DOI: 10.12809/hkjr1715374] [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: 11/05/2022] Open
|
10
|
Lee JCY, Shiu CK, Lai KC, Chan MK. Metal Artefact Reduction for Orthopaedic Devices Using Monoenergetic Extrapolation from Dual-energy Computed Tomography. Hong Kong J Radiol 2017. [DOI: 10.12809/hkjr1716423] [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: 11/05/2022] Open
|
11
|
Lee ACW, Tse KS, Lai KC, Chan MK, Tsang WK, Shiu CK, Cheng SS, Tang KW. Bone Surface Tumours and Tumour-like Conditions. Hong Kong J Radiol 2017. [DOI: 10.12809/hkjr1716433] [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: 11/05/2022] Open
|
12
|
Chan MK, Tang Y, Dorow CJ, Jeong J, Mangin-Thro L, Veit MJ, Ge Y, Abernathy DL, Sidis Y, Bourges P, Greven M. Hourglass Dispersion and Resonance of Magnetic Excitations in the Superconducting State of the Single-Layer Cuprate HgBa_{2}CuO_{4+δ} Near Optimal Doping. Phys Rev Lett 2016; 117:277002. [PMID: 28084762 DOI: 10.1103/physrevlett.117.277002] [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] [Received: 06/22/2016] [Indexed: 06/06/2023]
Abstract
We use neutron scattering to study magnetic excitations near the antiferromagnetic wave vector in the underdoped single-layer cuprate HgBa_{2}CuO_{4+δ} (superconducting transition temperature T_{c}≈88 K, pseudogap temperature T^{*}≈220 K). The response is distinctly enhanced below T^{*} and exhibits a Y-shaped dispersion in the pseudogap state, whereas the superconducting state features an X-shaped (hourglass) dispersion and a further resonancelike enhancement. A large spin gap of about 40 meV is observed in both states. This phenomenology is reminiscent of that exhibited by bilayer cuprates. The resonance spectral weight, irrespective of doping and compound, scales linearly with the putative binding energy of a spin exciton described by an itinerant-spin formalism.
Collapse
Affiliation(s)
- M K Chan
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
- Pulsed Field Facility, National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Y Tang
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - C J Dorow
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - J Jeong
- Laboratoire Léon Brillouin, CEA-CNRS, CEA-Saclay, 91191 Gif sur Yvette, France
| | - L Mangin-Thro
- Laboratoire Léon Brillouin, CEA-CNRS, CEA-Saclay, 91191 Gif sur Yvette, France
| | - M J Veit
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Y Ge
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - D L Abernathy
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Y Sidis
- Laboratoire Léon Brillouin, CEA-CNRS, CEA-Saclay, 91191 Gif sur Yvette, France
| | - P Bourges
- Laboratoire Léon Brillouin, CEA-CNRS, CEA-Saclay, 91191 Gif sur Yvette, France
| | - M Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| |
Collapse
|
13
|
Tsang KH, Chan WSW, Chan MK, Lai KC, Chan ACL. Synovial Sarcoma: Epidemiology, Prognosis, and Imaging in a Tertiary Referral Centre. Hong Kong J Radiol 2016. [DOI: 10.12809/hkjr1615298] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
|
14
|
Gottschalk MG, Cooper JD, Chan MK, Bot M, Penninx BWJH, Bahn S. Serum biomarkers predictive of depressive episodes in panic disorder. J Psychiatr Res 2016; 73:53-62. [PMID: 26687614 DOI: 10.1016/j.jpsychires.2015.11.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 11/13/2015] [Accepted: 11/20/2015] [Indexed: 01/30/2023]
Abstract
Panic disorder with or without comorbid agoraphobia (PD/PDA) has been linked to an increased risk to develop subsequent depressive episodes, yet the underlying pathophysiology of these disorders remains poorly understood. We aimed to identify a biomarker panel predictive for the development of a depressive disorder (major depressive disorder and/or dysthymia) within a 2-year-follow-up period. Blood serum concentrations of 165 analytes were evaluated in 120 PD/PDA patients without depressive disorder baseline diagnosis (6-month-recency) in the Netherlands Study of Depression and Anxiety (NESDA). We assessed the predictive performance of serum biomarkers, clinical, and self-report variables using receiver operating characteristics curves (ROC) and the area under the ROC curve (AUC). False-discovery-rate corrected logistic regression model selection of serum analytes and covariates identified an optimal predictive panel comprised of tetranectin and creatine kinase MB along with patient gender and scores from the Inventory of Depressive Symptomatology (IDS) rating scale. Combined, an AUC of 0.87 was reached for identifying the PD/PDA patients who developed a depressive disorder within 2 years (n = 44). The addition of biomarkers represented a significant (p = 0.010) improvement over using gender and IDS alone as predictors (AUC = 0.78). For the first time, we report on a combination of biological serum markers, clinical variables and self-report inventories that can detect PD/PDA patients at increased risk of developing subsequent depressive disorders with good predictive performance in a naturalistic cohort design. After an independent validation our proposed biomarkers could prove useful in the detection of at-risk PD/PDA patients, allowing for early therapeutic interventions and improving clinical outcome.
Collapse
Affiliation(s)
- M G Gottschalk
- Department of Chemical Engineering and Biotechnology, Cambridge Centre for Neuropsychiatric Research, University of Cambridge, Cambridge, UK
| | - J D Cooper
- Department of Chemical Engineering and Biotechnology, Cambridge Centre for Neuropsychiatric Research, University of Cambridge, Cambridge, UK
| | - M K Chan
- Department of Chemical Engineering and Biotechnology, Cambridge Centre for Neuropsychiatric Research, University of Cambridge, Cambridge, UK
| | - M Bot
- Department of Psychiatry, EMGO Institute for Health and Care Research and Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
| | - B W J H Penninx
- Department of Psychiatry, EMGO Institute for Health and Care Research and Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands.
| | - S Bahn
- Department of Chemical Engineering and Biotechnology, Cambridge Centre for Neuropsychiatric Research, University of Cambridge, Cambridge, UK.
| |
Collapse
|
15
|
|
16
|
Tsang KH, Cheung TY, Chan WSW, Chan MK. Primary Pericardial Osteosarcoma in an Elderly Patient. Hong Kong J Radiol 2015. [DOI: 10.12809/hkjr1515294] [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: 11/05/2022] Open
|
17
|
Tsang KH, Chan WSW, Shiu CK, Chan MK. The safety and tolerability of adenosine as a pharmacological stressor in stress perfusion cardiac magnetic resonance imaging in the Chinese population. Hong Kong Med J 2015; 21:524-7. [PMID: 26273015 DOI: 10.12809/hkmj144437] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [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: 11/05/2022] Open
Abstract
OBJECTIVE To investigate the safety profile and effectiveness of adenosine as a pharmacological stressor in patients with known or suspected coronary artery disease who underwent cardiac magnetic resonance imaging perfusion study. SETTING Regional hospital, Hong Kong. PATIENTS All patients who underwent adenosine stress cardiac magnetic resonance imaging from May 2013 to August 2013 were prospectively interviewed during the scan. MAIN OUTCOME MEASURES Common side-effects of adenosine as well as any other discomfort experienced during the scan were recorded. Haemodynamic changes including systolic and diastolic blood pressure and pulse rate before and during adenosine administration were also recorded. RESULTS There were 98 consecutive patients with a mean (± standard deviation) age of 64.0 ± 11.4 years (range, 10-83 years) and mean body weight of 67.5 ± 12.0 kg. Male-to-female ratio was 2.5:1. Of the 98 patients interviewed, 62 (63.3%) experienced one or more adenosine-associated adverse effects. Chest discomfort was most frequently experienced (48.0%), followed by dyspnoea (29.6%) and headache (20.4%). No life-threatening event occurred. Following adenosine administration, a significant rise in pulse rate (75.1 ± 14.3 vs 93.2 ± 14.7 beats/min; P<0.01) and a significant drop in diastolic blood pressure (75.1 ± 13.3 vs 68.0 ± 13.9 mm Hg; P<0.01) were noted. There was a general decrease in systolic blood pressure, although no statistically significant difference was observed (144.9 ± 17.6 vs 143.1 ± 21.4 mm Hg; P=0.18). CONCLUSION Adenosine stress cardiac magnetic resonance perfusion study is safe and well tolerated in clinical practice.
Collapse
Affiliation(s)
- K H Tsang
- Department of Radiology and Imaging, Queen Elizabeth Hospital, Jordan, Hong Kong
| | - Winnie S W Chan
- Department of Radiology and Imaging, Queen Elizabeth Hospital, Jordan, Hong Kong
| | - C K Shiu
- Department of Radiology and Imaging, Queen Elizabeth Hospital, Jordan, Hong Kong
| | - M K Chan
- Department of Radiology and Imaging, Queen Elizabeth Hospital, Jordan, Hong Kong
| |
Collapse
|
18
|
Gottschalk MG, Cooper JD, Chan MK, Bot M, Penninx BWJH, Bahn S. Discovery of serum biomarkers predicting development of a subsequent depressive episode in social anxiety disorder. Brain Behav Immun 2015; 48:123-31. [PMID: 25929723 DOI: 10.1016/j.bbi.2015.04.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 04/10/2015] [Accepted: 04/21/2015] [Indexed: 01/04/2023] Open
Abstract
Although social anxiety disorder (SAD) is strongly associated with the subsequent development of a depressive disorder (major depressive disorder or dysthymia), no underlying biological risk factors are known. We aimed to identify biomarkers which predict depressive episodes in SAD patients over a 2-year follow-up period. One hundred sixty-five multiplexed immunoassay analytes were investigated in blood serum of 143 SAD patients without co-morbid depressive disorders, recruited within the Netherlands Study of Depression and Anxiety (NESDA). Predictive performance of identified biomarkers, clinical variables and self-report inventories was assessed using receiver operating characteristics curves (ROC) and represented by the area under the ROC curve (AUC). Stepwise logistic regression resulted in the selection of four serum analytes (AXL receptor tyrosine kinase, vascular cell adhesion molecule 1, vitronectin, collagen IV) and four additional variables (Inventory of Depressive Symptomatology, Beck Anxiety Inventory somatic subscale, depressive disorder lifetime diagnosis, BMI) as optimal set of patient parameters. When combined, an AUC of 0.86 was achieved for the identification of SAD individuals who later developed a depressive disorder. Throughout our analyses, biomarkers yielded superior discriminative performance compared to clinical variables and self-report inventories alone. We report the discovery of a serum marker panel with good predictive performance to identify SAD individuals prone to develop subsequent depressive episodes in a naturalistic cohort design. Furthermore, we emphasise the importance to combine biological markers, clinical variables and self-report inventories for disease course predictions in psychiatry. Following replication in independent cohorts, validated biomarkers could help to identify SAD patients at risk of developing a depressive disorder, thus facilitating early intervention.
Collapse
Affiliation(s)
- M G Gottschalk
- Department of Chemical Engineering and Biotechnology, Cambridge Centre for Neuropsychiatric Research, University of Cambridge, Cambridge, UK
| | - J D Cooper
- Department of Chemical Engineering and Biotechnology, Cambridge Centre for Neuropsychiatric Research, University of Cambridge, Cambridge, UK
| | - M K Chan
- Department of Chemical Engineering and Biotechnology, Cambridge Centre for Neuropsychiatric Research, University of Cambridge, Cambridge, UK
| | - M Bot
- Department of Psychiatry, EMGO Institute for Health and Care Research and Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
| | - B W J H Penninx
- Department of Psychiatry, EMGO Institute for Health and Care Research and Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands.
| | - S Bahn
- Department of Chemical Engineering and Biotechnology, Cambridge Centre for Neuropsychiatric Research, University of Cambridge, Cambridge, UK; Department of Neuroscience, Erasmus Medical Center, Rotterdam, The Netherlands.
| |
Collapse
|
19
|
Bot M, Chan MK, Jansen R, Lamers F, Vogelzangs N, Steiner J, Leweke FM, Rothermundt M, Cooper J, Bahn S, Penninx BWJH. Serum proteomic profiling of major depressive disorder. Transl Psychiatry 2015; 5:e599. [PMID: 26171980 PMCID: PMC5068719 DOI: 10.1038/tp.2015.88] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 03/11/2015] [Accepted: 05/21/2015] [Indexed: 12/17/2022] Open
Abstract
Much has still to be learned about the molecular mechanisms of depression. This study aims to gain insight into contributing mechanisms by identifying serum proteins related to major depressive disorder (MDD) in a large psychiatric cohort study. Our sample consisted of 1589 participants of the Netherlands Study of Depression and Anxiety, comprising 687 individuals with current MDD (cMDD), 482 individuals with remitted MDD (rMDD) and 420 controls. We studied the relationship between MDD status and the levels of 171 serum proteins detected on a multi-analyte profiling platform using adjusted linear regression models. Pooled analyses of two independent validation cohorts (totaling 78 MDD cases and 156 controls) was carried out to validate our top markers. Twenty-eight analytes differed significantly between cMDD cases and controls (P < 0.05), whereas 10 partly overlapping markers differed significantly between rMDD cases and controls. Antidepressant medication use and comorbid anxiety status did not substantially impact on these findings. Sixteen of the cMDD-related markers had been assayed in the pooled validation cohorts, of which seven were associated with MDD. The analytes prominently associated with cMDD related to diverse cell communication and signal transduction processes (pancreatic polypeptide, macrophage migration inhibitory factor, ENRAGE, interleukin-1 receptor antagonist and tenascin-C), immune response (growth-regulated alpha protein) and protein metabolism (von Willebrand factor). Several proteins were implicated in depression. Changes were more prominent in cMDD, suggesting that molecular alterations in serum are associated with acute depression symptomatology. These findings may help to establish serum-based biomarkers of depression and could improve our understanding of its pathophysiology.
Collapse
Affiliation(s)
- M Bot
- Department of Psychiatry, EMGO Institute for Health and Care Research and Neuroscience Campus Amsterdam, VU University Medical Centre, Amsterdam, The Netherlands
| | - M K Chan
- Department of Chemical Engineering and Biotechnology, Institute of Biotechnology, University of Cambridge, Cambridge, UK
| | - R Jansen
- Department of Psychiatry, EMGO Institute for Health and Care Research and Neuroscience Campus Amsterdam, VU University Medical Centre, Amsterdam, The Netherlands
| | - F Lamers
- Department of Psychiatry, EMGO Institute for Health and Care Research and Neuroscience Campus Amsterdam, VU University Medical Centre, Amsterdam, The Netherlands
| | - N Vogelzangs
- Department of Psychiatry, EMGO Institute for Health and Care Research and Neuroscience Campus Amsterdam, VU University Medical Centre, Amsterdam, The Netherlands
| | - J Steiner
- Department of Psychiatry, University of Magdeburg, Magdeburg, Germany
| | - F M Leweke
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - M Rothermundt
- Department of Psychiatry, University of Münster, Münster, Germany,Evangelisches Klinikum Niederrhein, Oberhausen, Germany
| | - J Cooper
- Department of Chemical Engineering and Biotechnology, Institute of Biotechnology, University of Cambridge, Cambridge, UK
| | - S Bahn
- Department of Chemical Engineering and Biotechnology, Institute of Biotechnology, University of Cambridge, Cambridge, UK,Department of Neuroscience, Erasmus Medical Center, Rotterdam, The Netherlands,Dr S Bahn, Department of Chemical Engineering and Biotechnology, Institute of Biotechnology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QT, UK
| | - B W J H Penninx
- Department of Psychiatry, EMGO Institute for Health and Care Research and Neuroscience Campus Amsterdam, VU University Medical Centre, Amsterdam, The Netherlands,Dr BWJH Penninx, Department of Psychiatry, EMGO Institute for Health and Care Research and Neuroscience Campus Amsterdam, VU University Medical Center, AJ Ernststraat 1187, 1081 HL Amsterdam, The Netherlands. E-mail: or
| |
Collapse
|
20
|
Affiliation(s)
- M K Chan
- Department of Medicine, University of Hong Kong, Queen Mary Hospital
| |
Collapse
|
21
|
Tabis W, Li Y, Le Tacon M, Braicovich L, Kreyssig A, Minola M, Dellea G, Weschke E, Veit MJ, Ramazanoglu M, Goldman AI, Schmitt T, Ghiringhelli G, Barišić N, Chan MK, Dorow CJ, Yu G, Zhao X, Keimer B, Greven M. Charge order and its connection with Fermi-liquid charge transport in a pristine high-T(c) cuprate. Nat Commun 2014; 5:5875. [PMID: 25522689 DOI: 10.1038/ncomms6875] [Citation(s) in RCA: 236] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 11/17/2014] [Indexed: 11/09/2022] Open
Abstract
Electronic inhomogeneity appears to be an inherent characteristic of the enigmatic cuprate superconductors. Here we report the observation of charge-density-wave correlations in the model cuprate superconductor HgBa2CuO(4+δ) (T(c)=72 K) via bulk Cu L3-edge-resonant X-ray scattering. At the measured hole-doping level, both the short-range charge modulations and Fermi-liquid transport appear below the same temperature of about 200 K. Our result points to a unifying picture in which these two phenomena are preceded at the higher pseudogap temperature by q=0 magnetic order and the build-up of significant dynamic antiferromagnetic correlations. The magnitude of the charge modulation wave vector is consistent with the size of the electron pocket implied by quantum oscillation and Hall effect measurements for HgBa2CuO(4+δ) and with corresponding results for YBa2Cu3O(6+δ), which indicates that charge-density-wave correlations are universally responsible for the low-temperature quantum oscillation phenomenon.
Collapse
Affiliation(s)
- W Tabis
- 1] School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA [2] AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. Mickiewicza 30, 30-059 Krakow, Poland
| | - Y Li
- 1] International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China [2] Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - M Le Tacon
- Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany
| | - L Braicovich
- CNR-SPIN, CNISM and Dipartimento di Fisica, Politecnico di Milano, I-20133 Milano, Italy
| | - A Kreyssig
- Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
| | - M Minola
- Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany
| | - G Dellea
- CNR-SPIN, CNISM and Dipartimento di Fisica, Politecnico di Milano, I-20133 Milano, Italy
| | - E Weschke
- Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, D-12489 Berlin, Germany
| | - M J Veit
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M Ramazanoglu
- 1] Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA [2] Physics Engineering Department, ITU, Maslak 34469, Istanbul, Turkey
| | - A I Goldman
- Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
| | - T Schmitt
- Research Department Synchrotron Radiation and Nanotechnology, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - G Ghiringhelli
- CNR-SPIN, CNISM and Dipartimento di Fisica, Politecnico di Milano, I-20133 Milano, Italy
| | - N Barišić
- 1] School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA [2] Service de Physique de l'Etat Condensé, CEA-DSM-IRAMIS, F-91198 Gif-sur-Yvette, France [3] Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
| | - M K Chan
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - C J Dorow
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - G Yu
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - X Zhao
- 1] School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA [2] State Key Lab of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, China
| | - B Keimer
- Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany
| | - M Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| |
Collapse
|
22
|
Chan MK, Veit MJ, Dorow CJ, Ge Y, Li Y, Tabis W, Tang Y, Zhao X, Barišić N, Greven M. In-plane magnetoresistance obeys Kohler's rule in the pseudogap phase of cuprate superconductors. Phys Rev Lett 2014; 113:177005. [PMID: 25379934 DOI: 10.1103/physrevlett.113.177005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Indexed: 06/04/2023]
Abstract
We report in-plane resistivity (ρ) and transverse magnetoresistance (MR) measurements for underdoped HgBa(2)CuO(4+δ) (Hg1201). Contrary to the long-standing view that Kohler's rule is strongly violated in underdoped cuprates, we find that it is in fact satisfied in the pseudogap phase of Hg1201. The transverse MR shows a quadratic field dependence, δρ/ρ(0)=aH(2), with a(T)∝T(-4). In combination with the observed ρ∝T(2) dependence, this is consistent with a single Fermi-liquid quasiparticle scattering rate. We show that this behavior is typically masked in cuprates with lower structural symmetry or strong disorder effects.
Collapse
Affiliation(s)
- M K Chan
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M J Veit
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - C J Dorow
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Y Ge
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Y Li
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - W Tabis
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA and AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. A. Mickiewicza 30, 30-059 Krakow, Poland
| | - Y Tang
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - X Zhao
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA and State Key Lab of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, China
| | - N Barišić
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA and Service de Physique de l'Etat Condensé, CEA-DSM-IRAMIS, F 91198 Gif-sur-Yvette, France and Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria
| | - M Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| |
Collapse
|
23
|
Cilento F, Dal Conte S, Coslovich G, Peli S, Nembrini N, Mor S, Banfi F, Ferrini G, Eisaki H, Chan MK, Dorow CJ, Veit MJ, Greven M, van der Marel D, Comin R, Damascelli A, Rettig L, Bovensiepen U, Capone M, Giannetti C, Parmigiani F. Photo-enhanced antinodal conductivity in the pseudogap state of high-Tc cuprates. Nat Commun 2014; 5:4353. [PMID: 25014895 PMCID: PMC4104437 DOI: 10.1038/ncomms5353] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Accepted: 06/07/2014] [Indexed: 11/24/2022] Open
Abstract
A major challenge in understanding the cuprate superconductors is to clarify the nature of the fundamental electronic correlations that lead to the pseudogap phenomenon. Here we use ultrashort light pulses to prepare a non-thermal distribution of excitations and capture novel properties that are hidden at equilibrium. Using a broadband (0.5–2 eV) probe, we are able to track the dynamics of the dielectric function and unveil an anomalous decrease in the scattering rate of the charge carriers in a pseudogap-like region of the temperature (T) and hole-doping (p) phase diagram. In this region, delimited by a well-defined T*neq(p) line, the photoexcitation process triggers the evolution of antinodal excitations from gapped (localized) to delocalized quasiparticles characterized by a longer lifetime. The novel concept of photo-enhanced antinodal conductivity is naturally explained within the single-band Hubbard model, in which the short-range Coulomb repulsion leads to a k-space differentiation between nodal quasiparticles and antinodal excitations. The pseudogap phase exhibited by the cuprates is almost as enigmatic as superconductivity in these materials itself. A time-resolved study performed by Cilento et al. suggests that this state can be photoexcited into a transient non-equilibrium state that is more conductive than the equilibrium state.
Collapse
Affiliation(s)
- F Cilento
- Elettra-Sincrotrone Trieste S.C.p.A., I-34149 Basovizza, Italy
| | - S Dal Conte
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] i-LAMP (Interdisciplinary Laboratories for Advanced Materials Physics), Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [3]
| | - G Coslovich
- 1] Department of Physics, Università degli Studi di Trieste, I-34127 Trieste, Italy [2]
| | - S Peli
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] Department of Physics, Università degli Studi di Milano, I-20133 Milano, Italy
| | - N Nembrini
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] Department of Physics, Università degli Studi di Milano, I-20133 Milano, Italy
| | - S Mor
- Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
| | - F Banfi
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] i-LAMP (Interdisciplinary Laboratories for Advanced Materials Physics), Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
| | - G Ferrini
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] i-LAMP (Interdisciplinary Laboratories for Advanced Materials Physics), Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
| | - H Eisaki
- Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan
| | - M K Chan
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - C J Dorow
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M J Veit
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - D van der Marel
- Département de Physique de la Matière Condensée, Université de Genève, CH1211 Genève, Switzerland
| | - R Comin
- 1] Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1 [2] Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - A Damascelli
- 1] Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1 [2] Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - L Rettig
- 1] Fakultaet fuer Physik and Zentrum für Nanointegration (CENIDE), Universitaet Duisburg-Essen, 47048 Duisburg, Germany [2]
| | - U Bovensiepen
- Fakultaet fuer Physik and Zentrum für Nanointegration (CENIDE), Universitaet Duisburg-Essen, 47048 Duisburg, Germany
| | - M Capone
- CNR-IOM Democritos National Simulation Center and Scuola Internazionale Superiore di Studi Avanzati (SISSA), Via Bonomea 265, 34136 Trieste, Italy
| | - C Giannetti
- 1] Department of Physics, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy [2] i-LAMP (Interdisciplinary Laboratories for Advanced Materials Physics), Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy
| | - F Parmigiani
- 1] Elettra-Sincrotrone Trieste S.C.p.A., I-34149 Basovizza, Italy [2] Department of Physics, Università degli Studi di Trieste, I-34127 Trieste, Italy
| |
Collapse
|
24
|
Lau TK, Cheung SW, Lo PSS, Pursley AN, Chan MK, Jiang F, Zhang H, Wang W, Jong LFJ, Yuen OKC, Chan HYC, Chan WSK, Choy KW. Non-invasive prenatal testing for fetal chromosomal abnormalities by low-coverage whole-genome sequencing of maternal plasma DNA: review of 1982 consecutive cases in a single center. Ultrasound Obstet Gynecol 2014; 43:254-264. [PMID: 24339153 DOI: 10.1002/uog.13277] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [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: 11/10/2013] [Revised: 12/06/2013] [Accepted: 12/10/2013] [Indexed: 06/03/2023]
Abstract
OBJECTIVE To review the performance of non-invasive prenatal testing (NIPT) by low-coverage whole-genome sequencing of maternal plasma DNA at a single center. METHODS The NIPT result and pregnancy outcome of 1982 consecutive cases were reviewed. NIPT was based on low coverage (0.1×) whole-genome sequencing of maternal plasma DNA. All subjects were contacted for pregnancy and fetal outcome. RESULTS Of the 1982 NIPT tests, a repeat blood sample was required in 23 (1.16%). In one case, a conclusive report could not be issued, probably because of an abnormal vanished twin fetus. NIPT was positive for common trisomies in 29 cases (23 were trisomy 21, four were trisomy 18 and two were trisomy 13); all were confirmed by prenatal karyotyping (specificity=100%). In addition, 11 cases were positive for sex-chromosomal abnormalities (SCA), and nine cases were positive for other aneuploidies or deletion/duplication. Fourteen of these 20 subjects agreed to undergo further investigations, and the abnormality was found to be of fetal origin in seven, confined placental mosaicism (CPM) in four, of maternal origin in two and not confirmed in one. Overall, 85.7% of the NIPT-suspected SCA were of fetal origin, and 66.7% of the other abnormalities were caused by CPM. Two of the six cases suspected or confirmed to have CPM were complicated by early-onset growth restriction requiring delivery before 34 weeks. Fetal outcome of the NIPT-negative cases was ascertained in 1645 (85.15%). Three chromosomal abnormalities were not detected by NIPT, including one case each of a balanced translocation, unbalanced translocation and triploidy. There were no known false negatives involving the common trisomies (sensitivity=100%). CONCLUSIONS Low-coverage whole-genome sequencing of maternal plasma DNA was highly accurate in detecting common trisomies. It also enabled the detection of other aneuploidies and structural chromosomal abnormalities with high positive predictive value.
Collapse
Affiliation(s)
- T K Lau
- Fetal Medicine Centre, Paramount Medical Centre, Hong Kong, China
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Mounce AM, Oh S, Lee JA, Halperin WP, Reyes AP, Kuhns PL, Chan MK, Dorow C, Ji L, Xia D, Zhao X, Greven M. Absence of static loop-current magnetism at the apical oxygen site in HgBa2CuO4+δ from NMR. Phys Rev Lett 2013; 111:187003. [PMID: 24237553 DOI: 10.1103/physrevlett.111.187003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Indexed: 06/02/2023]
Abstract
The simple structure of HgBa(2)CuO(4+δ) (Hg1201) is ideal among cuprates for study of the pseudogap phase as a broken symmetry state. We have performed (17)O nuclear magnetic resonance on an underdoped Hg1201 crystal with a transition temperature of 74 K to look for circulating loop currents proposed theoretically and inferred from neutron scattering. The narrow spectra preclude static local fields in the pseudogap phase at the apical site, suggesting that the moments observed with neutrons are fluctuating. The nuclear magnetic resonance frequency shifts are consistent with a dipolar field from the Cu(2+) site.
Collapse
Affiliation(s)
- A M Mounce
- Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Li Y, Le Tacon M, Matiks Y, Boris AV, Loew T, Lin CT, Chen L, Chan MK, Dorow C, Ji L, Barišić N, Zhao X, Greven M, Keimer B. Doping-dependent photon scattering resonance in the model high-temperature superconductor HgBa2CuO4+δ revealed by Raman scattering and optical ellipsometry. Phys Rev Lett 2013; 111:187001. [PMID: 24237551 DOI: 10.1103/physrevlett.111.187001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Indexed: 06/02/2023]
Abstract
We study the model high-temperature superconductor HgBa(2)CuO(4+δ) with electronic Raman scattering and optical ellipsometry over a wide doping range. The dependence of the resonant Raman cross section on the incident photon energy changes drastically as a function of doping, in a manner that corresponds to a rearrangement of the interband optical transitions seen with ellipsometry. This doping-dependent Raman resonance allows us to reconcile the apparent discrepancy between Raman and x-ray detection of magnetic fluctuations in superconducting cuprates. Intriguingly, the strongest variation occurs across the doping level where the antinodal superconducting gap appears to reach its maximum.
Collapse
Affiliation(s)
- Yuan Li
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China and Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Choi H, Lau TK, Jiang FM, Chan MK, Zhang HY, Lo PSS, Chen F, Zhang L, Wang W. Fetal aneuploidy screening by maternal plasma DNA sequencing: 'false positive' due to confined placental mosaicism. Prenat Diagn 2012. [PMID: 23192749 DOI: 10.1002/pd.4024] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
28
|
Pasic MD, Colantonio DA, Chan MK, Venner AA, Brinc D, Adeli K. Influence of fasting and sample collection time on 38 biochemical markers in healthy children: a CALIPER substudy. Clin Biochem 2012; 45:1125-30. [PMID: 22820439 DOI: 10.1016/j.clinbiochem.2012.07.089] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 07/05/2012] [Accepted: 07/08/2012] [Indexed: 10/28/2022]
Abstract
OBJECTIVES Fasting samples can be difficult to obtain in the pediatric setting, particularly in neonates. As part of the Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER), we aimed to determine if there are differences in serum concentrations of pediatric biochemical markers measured at fasting, postprandial, and random time points throughout the day. DESIGN AND METHODS Blood was drawn from 27 healthy children and adolescents (aged 4-18) with informed consent at 4 time points: after overnight fast, mid-morning after breakfast, within 2h after lunch, and late afternoon. The effect of fasting on 38 chemistries was evaluated by paired, two-tailed student'st-tests. Analysis of the effect of time of day was done using paired, repeated-measures ANOVA. RESULTS Fasting significantly affected 22 analytes, with HDL cholesterol being the most highly affected. Values tended to decrease postprandially, except for five analytes, including triglycerides, which increased. By ANOVA, 28 chemistries significantly differed across times of day tested. CONCLUSIONS Fasting is necessary for analysis of certain chemistries in pediatric subjects. Pediatricians should consider diurnal factors when ordering non-fasting tests and interpreting test results.
Collapse
Affiliation(s)
- M D Pasic
- Clinical Biochemistry Division, Department of Pediatric Laboratory Medicine, Hospital for Sick Children, Toronto, Ontario, Canada
| | | | | | | | | | | |
Collapse
|
29
|
Li Y, Le Tacon M, Bakr M, Terrade D, Manske D, Hackl R, Ji L, Chan MK, Barišić N, Zhao X, Greven M, Keimer B. Feedback effect on high-energy magnetic fluctuations in the model high-temperature superconductor HgBa2CuO(4+δ) observed by electronic Raman scattering. Phys Rev Lett 2012; 108:227003. [PMID: 23003643 DOI: 10.1103/physrevlett.108.227003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Indexed: 06/01/2023]
Abstract
We use electronic Raman scattering to study the model single-layer cuprate superconductor HgBa(2)CuO(4+δ). In an overdoped sample, we observe a pronounced amplitude enhancement of a high-energy peak related to two-magnon excitations in insulating cuprates upon cooling below the critical temperature T(c). This effect is accompanied by the appearance of the superconducting gap and a pairing peak above the gap in the Raman spectrum, and it can be understood as a hitherto-undetected feedback effect on the high-energy magnetic fluctuations due to the Cooper pairing interaction. This implies a direct involvement of the high-energy magnetic fluctuations in the pairing mechanism. All of these effects occur already above T(c) in two underdoped samples, demonstrating a related feedback mechanism associated with the pseudogap.
Collapse
Affiliation(s)
- Yuan Li
- Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Garlid ES, Hu QO, Chan MK, Palmstrøm CJ, Crowell PA. Electrical measurement of the direct spin hall effect in Fe/InxGa(1-x)As heterostructures. Phys Rev Lett 2010; 105:156602. [PMID: 21230922 DOI: 10.1103/physrevlett.105.156602] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Indexed: 05/30/2023]
Abstract
We report on an all-electrical measurement of the spin Hall effect in epitaxial Fe/InxGa(1-x)As heterostructures with n-type (Si) channel doping and highly doped Schottky tunnel barriers. A transverse spin current generated by an ordinary charge current flowing in the InxGa(1-x)As is detected by measuring the spin accumulation at the edges of the channel. The spin accumulation is identified through the observation of a Hanle effect in the voltage measured by pairs of ferromagnetic Hall contacts. We investigate the bias and temperature dependence of the resulting Hanle signal and determine the skew and side-jump contributions to the total spin Hall conductivity.
Collapse
Affiliation(s)
- E S Garlid
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | | | | | | | |
Collapse
|
31
|
Rampakakis E, Di Paola D, Chan MK, Zannis-Hadjopoulos M. Dynamic changes in chromatin structure through post-translational modifications of histone H3 during replication origin activation. J Cell Biochem 2009; 108:400-7. [PMID: 19585526 DOI: 10.1002/jcb.22266] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Genome duplication relies on the timely activation of multiple replication origins throughout the genome during S phase. Each origin is marked by the assembly of a multiprotein pre-replication complex (pre-RC) and the recruitment of the replicative machinery, which can gain access to replication origins on the DNA through the barrier of specific chromatin structures. Inheritance of the genetic information is further accompanied by maintenance and inheritance of the epigenetic marks, which are accomplished by the activity of histone and DNA modifying enzymes traveling with the replisome. Here, we studied the changes in the chromatin structure at the loci of three replication origins, the early activated human lamin B2 (LB2) and monkey Ors8 (mOrs8) origins and the late-activated human homologue of the latter (hOrs8), during their activation, by measuring the abundance of post-translationally modified histone H3. The data show that dynamic changes in the levels of acetylated, methylated and phosphorylated histone H3 occur during the initiation of DNA replication at these three origin loci, which differ between early- and late-firing origins as well as between human- and monkey-derived cell lines. These results suggest that specific histone modifications are associated with origin firing, temporal activation and replication fork progression and underscore the importance of species specificity.
Collapse
Affiliation(s)
- E Rampakakis
- Rosalind and Morris Goodman Cancer Center, Department of Biochemistry, McGill University, Montreal, Quebec, Canada H3A 1A3
| | | | | | | |
Collapse
|
32
|
Fung HS, Lau S, Chan MK, Tang KW, Cheung YL, Chan SCH. Persistent sciatic artery complicated by aneurysm formation and thrombosis. Hong Kong Med J 2008; 14:492-494. [PMID: 19060351] [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: 05/27/2023] Open
Abstract
A persistent sciatic artery is a rare embryological anomaly. We report a case of a persistent sciatic artery with aneurysm formation and thrombosis in a patient with rheumatoid arthritis/systemic lupus erythematosus overlap syndrome and Raynaud's phenomenon. The diagnosis and complete, accurate evaluation of the arterial anatomy of the lower limb were achieved using computed tomographic angiography.
Collapse
Affiliation(s)
- H S Fung
- Department of Radiology and Imaging, Queen Elizabeth Hospital, Hong Kong.
| | | | | | | | | | | |
Collapse
|
33
|
Lee S, Chan JWM, Chan SCH, Chan YH, Kwan TL, Chan MK, Ng CK, Lee MP, Law WL, Mok TYW. Bronchial artery embolisation can be equally safe and effective in the management of chronic recurrent haemoptysis. Hong Kong Med J 2008; 14:14-20. [PMID: 18239238] [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: 05/25/2023] Open
Abstract
OBJECTIVE To examine the efficacy and safety of bronchial artery embolisation in patients with acute major haemoptysis and those with chronic recurrent haemoptysis. DESIGN Retrospective review of clinical records. SETTING Regional hospital, Hong Kong. PATIENTS Clinical records of 70 consecutive patients who had undergone bronchial artery embolisation in Queen Elizabeth Hospital from 1998 to 2003 were reviewed. Altogether 74 bronchial artery embolisation procedures were attempted, 46 (62%) for acute major haemoptysis, and 28 (38%) for chronic recurrent bleeding. Follow-up data were available for 32 patients. MAIN OUTCOME MEASURES After bronchial artery embolisation, the Kaplan-Meier method and log-rank tests were used to compare the probability of recurrence in the two patient categories. RESULTS Overall immediate control was attained following 99% of the procedures, with a complication rate of 13%; all complications were mild and self-limiting. For the 32 patients (19 having acute major haemoptysis and 13 having chronic recurrent bleeding) with follow-up data available, the overall recurrence rate was 36% (26% in the acute and 47% in chronic group). No statistically significant difference in recurrence probability between the two groups was observed (P=0.24). Presence of active pulmonary tuberculosis was associated with increased risk of recurrence (P=0.005). CONCLUSION Bronchial artery embolisation was noted to be effective and safe in both acute major and chronic recurrent haemoptysis.
Collapse
Affiliation(s)
- Samuel Lee
- Department of Medicine, Queen Elizabeth Hospital, 30 Gascoigne Road, Kowloon, Hong Kong.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Mak HLJ, Kwok PCH, Chau HHL, Chan MK, Chan SCH, Chan SCS. Uterine fibroid embolisation in Chinese women: medium-term results. Hong Kong Med J 2006; 12:361-7. [PMID: 17028356] [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: 05/12/2023] Open
Abstract
OBJECTIVE To evaluate the medium-term results of uterine fibroid embolisation in Chinese women with symptomatic uterine fibroids. DESIGN Prospective case series study. SETTING Gynaecology and Interventional Radiology units in a public hospital, Hong Kong. PATIENTS Patients with symptomatic fibroids who underwent uterine fibroid embolisation in Queen Elizabeth Hospital from October 1998 to June 2004. RESULTS Fifty women (mean age, 42.9 years; median follow-up period, 27.5 months) were recruited. Most (82%) had menorrhagia as the chief presenting symptom. Embolisation was successful in 49 (98%) women. Complications occurred in 12 (24%) patients, but were all self-limiting. Significant decrease in the median clinical uterine size (14 weeks vs 10 weeks) and median volume of the largest fibroid on magnetic resonance imaging (157.9 mL vs 45 mL) were observed during the first year. The reduction seemed to be maintained till the last follow-up. Menorrhagia improved in 34 (84%) patients, dysmenorrhoea in 28 (88%), pelvic pain in 18 (82%) and abdominal mass in 15 (83%). Poor response was found for urinary symptoms (29% improvement). Eight (16%) patients underwent hysterectomies after uterine fibroid embolisation. On logistic regression analysis, the only significant predictive factor for symptomatic improvement was fibroid volume reduction at 6 months (P=0.03). CONCLUSION Uterine fibroid embolisation is an effective uterine-preserving therapy in patients with symptomatic fibroids; overall symptomatic improvement was estimated as 80%. Uterine or fibroid size reduction correlated well with clinical outcome. The impact of uterine fibroid embolisation on young women wishing to conceive is yet to be determined.
Collapse
Affiliation(s)
- H L J Mak
- Department of Obstetrics and Gynaecology, Queen Elizabeth Hospital, 30 Gascoigne Road, Kowloon, Hong Kong.
| | | | | | | | | | | |
Collapse
|
35
|
Yip PSC, Lam YL, Chan MK, Shu JSJ, Lai KC, So YC. Computed tomography-guided percutaneous radiofrequency ablation of osteoid osteoma: local experience. Hong Kong Med J 2006; 12:305-9. [PMID: 16912358] [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: 05/11/2023] Open
Abstract
Osteoid osteoma is a slow-growing tumour with limited growth potential. In the past, treatment comprised open surgery with en-bloc resection or curettage of the tumour. In recent years, various minimally invasive percutaneous treatments have gained popularity. We report on six patients who underwent computed tomography-guided percutaneous radiofrequency ablations of osteoid osteomas between January 2000 and December 2003 in a regional hospital in Hong Kong. Technical success was achieved in all procedures, with a mean follow-up of 40 months (range, 18-65 months). Five of the six patients achieved complete pain relief after the procedure and remained pain-free on subsequent follow-up. One patient with persistent symptoms after the first ablation was successfully treated with a second ablation. The mean in-hospital stay was 2.4 days. Progress in radiological healing was observed in all patients. There was one complication of skin burn over the needle entry site. Our experience shows that percutaneous computed tomography-guided radiofrequency ablation is a minimally invasive and cost-effective treatment for osteoid osteoma.
Collapse
Affiliation(s)
- P S C Yip
- Department of Orthopaedics and Traumatology, Queen Elizabeth Hospital, Hong Kong.
| | | | | | | | | | | |
Collapse
|
36
|
Ng CM, Yuen HKL, Choi KL, Chan MK, Yuen KT, Ng YW, Tiu SC. Combined orbital irradiation and systemic steroids compared with systemic steroids alone in the management of moderate-to-severe Graves' ophthalmopathy: a preliminary study. Hong Kong Med J 2005; 11:322-30. [PMID: 16219950] [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: 05/04/2023] Open
Abstract
OBJECTIVE To assess the efficacy and safety of combined orbital irradiation and systemic steroids in the management of moderate-to-severe Graves' ophthalmopathy. DESIGN Single-blind randomised prospective study. SETTING Regional hospital, Hong Kong. PATIENTS Sixteen patients with active moderate-to-severe Graves' ophthalmopathy who were randomly assigned to steroid therapy (ST group) or combination therapy of orbital irradiation and systemic steroids (SRT group) between June 2000 and June 2003. MAIN OUTCOME MEASURES NOSPECS scoring system, total eye score, subjective eye score, and extra-ocular muscle thickness as determined by either computed tomographic or magnetic resonance imaging scans. RESULTS The study was completed by 15 of 16 patients. Both groups experienced improvement in total eye score, soft tissue swelling, ocular motility, visual acuity, and subjective eye score at 52-week follow-up. Total eye score improved earlier in the SRT group, achieving statistical significance (P<0.05) at as early as 4 weeks of follow-up. Improvement in ocular parameters was greater and led to a significantly greater reduction in total eye score than in the ST group at weeks 16, 24, and 52. Maximum extra-ocular muscle thickness was significantly reduced in the SRT group only. No change was observed in proptosis in either group. No serious adverse effect was observed with the addition of orbital irradiation to steroid therapy. CONCLUSION A combination of orbital irradiation and systemic steroids is well tolerated and more effective than steroids alone in the treatment of active moderate-to-severe Graves' ophthalmopathy. It achieves greater and more rapid improvement in soft tissue swelling, ocular motility, and visual acuity.
Collapse
Affiliation(s)
- C M Ng
- Department of Medicine, Queen Elizabeth Hospital, 30 Gascoigne Road, Hong Kong.
| | | | | | | | | | | | | |
Collapse
|
37
|
Liu X, Chan MK, Hennessey B, Rübenach T, Alay G. Quantifying touch-feel perception on automotive interiors by a multi-function tribological probe microscope. ACTA ACUST UNITED AC 2005. [DOI: 10.1088/1742-6596/13/1/082] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
38
|
Chan MK, Othman R, Zubir D, Salmijah S. Induction of a putative metallothionein gene in the blood cockle, Anadara granosa, exposed to cadmium. Comp Biochem Physiol C Toxicol Pharmacol 2002; 131:123-32. [PMID: 11879780 DOI: 10.1016/s1532-0456(01)00293-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [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: 10/17/2022]
Abstract
The relationship between a putative metallothionein gene (MT) and exposure to cadmium (Cd) in blood cockles (Anadara granosa) is reported. In a 96-h dose-response experiment, mortality of cockles was found to proportionately increase in the range of 0.2-5.0 mg/l Cd with a calculated LC(50) of 2.94 mg/l. Exposure to 0.25 mg/l Cd for 16 days caused significant increases (P<0.05) in Cd concentrations in whole tissues, gills and hepatopancreas, and the accumulation of Cd in these tissues increased with the duration of exposure. Two cDNA libraries constructed using the hepatopancreas from control and Cd-treated cockles gave titres of 5.62 x 10(5) and 1.94 x 10(5) pfu/microg vector, respectively. A putative MT gene, AnaMT, of 510 nucleotides in length, was isolated from the treated cDNA library using a heterologous probe MT20 from the blue mussel, Mytilus edulis. Northern analyses using AnaMT as a probe indicated low expression of the MT mRNA in control animals. In cockles treated with 0.25 mg/l Cd for 4 days, MT mRNA level increased to approximately 168%, but declined to 108% at day 8. After 12 and 16 days of Cd treatment, expression of the MT gene was 138% and 187%, respectively, compared to the controls. These observations suggest that induction of the MT gene by a sublethal dose of Cd is rapid, occurring within 4 days of treatment.
Collapse
Affiliation(s)
- M K Chan
- School of Environmental Science and Natural Resources, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
| | | | | | | |
Collapse
|
39
|
Mak YK, Chan CH, So CC, Chan MK, Chu YC. Idiopathic myelofibrosis with extramedullary haemopoiesis involving the urinary bladder in a Chinese lady. Clin Lab Haematol 2002; 24:55-9. [PMID: 11843900 DOI: 10.1046/j.1365-2257.2002.00424.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Extramedullary haemopoiesis (EMH) associated with idiopathic myelofibrosis most commonly involves the reticuloendothelial organs, such as the spleen and liver, although ectopic haemopoietic tissue has also been described rarely in the lymph nodes, skin, gastrointestinal tract, pleura, peritoneum, central nervous system, and genital and urinary tracts. We report on a 54-year-old Chinese lady with a long history of idiopathic myelofibrosis who presented with gross haematuria and left hydronephrosis due to EMH in the bladder trigone. Cystoscopic examination revealed a sessile necrotic papillary growth at the trigone, obstructing the left ureteric orifice. Transurethral resection of the bladder tumour was performed, and microscopic examination of the tumour chips demonstrated atypical megakaryocytes, immature granulocytes and normoblasts, confirming the presence of EMH. The residual bladder tumour responded well to low dose radiotherapy, with subsequent disappearance of haematuria and normalization of ultrasonogram findings.
Collapse
Affiliation(s)
- Y K Mak
- Department of Medicine, Queen Elizabeth Hospital, Kowloon, China
| | | | | | | | | |
Collapse
|
40
|
Abstract
OBJECTIVE To describe the MRI features of nodular fasciitis and to review the clinical, MRI and histologic aspects of the tumor. DESIGN AND PATIENTS Three patients with biopsy-proven nodular fasciitis were selected for a retrospective study. A literature review was also carried out. RESULTS AND CONCLUSIONS All the lesions appeared slightly hyperintense to skeletal muscle on T1-weighted images, and hyperintense on T2-weighted images with fat saturation [either frequency saturation or Short TI Inversion Recovery (STIR) sequences]. Two enhanced homogeneously after intravenous gadolinium, whereas the third showed heterogeneous enhancement with a nonenhancing area. Despite the difference in enhancing patterns, the histologic appearances of these lesions were similar. Our study shows that the MRI appearance of nodular fasciitis may not be related to the location of lesion. It is thought that the age of nodular fasciitis may reflect its gross morphology, and it is possible that the MRI and histologic appearances could correlate with the age of the lesion, but it would require a larger series to evaluate this concept.
Collapse
Affiliation(s)
- L Y J Leung
- Department of Radiology and Imaging, Queen Elizabeth Hospital, 30 Gascoigne Road, Hong Kong.
| | | | | | | | | |
Collapse
|
41
|
Abstract
Chondroblastoma of the vertebra is a very rare condition. To our knowledge fewer than 20 cases have been reported in the world literature. We report a 54-year-old man with chondroblastoma of the fifth lumbar vertebra. The clinical and radiological aspects of the tumor are discussed, emphasizing the presence of an extraosseous mass suggestive of locally aggressive behavior.
Collapse
Affiliation(s)
- L Y Leung
- Department of Radiology and Imaging, Queen Elizabeth Hospital, 30 Gascoigne Road, Hong Kong.
| | | | | | | |
Collapse
|
42
|
Boorstein RJ, Cummings A, Marenstein DR, Chan MK, Ma Y, Neubert TA, Brown SM, Teebor GW. Definitive identification of mammalian 5-hydroxymethyluracil DNA N-glycosylase activity as SMUG1. J Biol Chem 2001; 276:41991-7. [PMID: 11526119 DOI: 10.1074/jbc.m106953200] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Purification from calf thymus of a DNA N-glycosylase activity (HMUDG) that released 5-hydroxymethyluracil (5hmUra) from the DNA of Bacillus subtilis phage SPO1 was undertaken. Analysis of the most purified fraction by SDS-polyacrylamide gel electrophoresis revealed a multiplicity of protein species making it impossible to identify HMUDG by inspection. Therefore, we renatured the enzyme after SDS-polyacrylamide gel electrophoresis and assayed slices of the gel for DNA N-glycosylase activity directed against 5hmUra. Maximum enzymatic activity was identified between molecular mass markers 30 and 34 kDa. Protein was extracted from gel slices and subjected to tryptic digestion and analysis by mass spectrometry. Analysis revealed the presence of 11 peptides that were homologous or identical to the sequence of the recently characterized human single-stranded monofunctional uracil DNA N-glycosylase (hSMUG1). The cDNA of hSMUG1 was isolated and expressed as a recombinant glutathione S-transferase fusion protein that was shown to release 5hmUra with 20x the specific activity of the most purified bovine fraction. We conclude that hSMUG1 and HMUDG are the same protein.
Collapse
Affiliation(s)
- R J Boorstein
- Department of Pathology and Kaplan Comprehensive Cancer Center, New York University School of Medicine, New York, New York 10016, USA
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Chang AR, Liang XM, Chan AT, Chan MK, Teo PM, Johnson PJ. The use of brush cytology and directed biopsies for the detection of nasopharyngeal carcinoma and precursor lesions. Head Neck 2001; 23:637-45. [PMID: 11443746 DOI: 10.1002/hed.1090] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND It has been proposed that nasopharyngeal carcinoma (NPC) has an early noninvasive stage, designated nasopharyngeal intraepithelial neoplasia (NPIN). Hence, the detection and treatment of NPIN will prevent NPC from developing, and this would be similar to the strategies used for cervical cancer prevention. We wanted to ascertain the feasibility of using a brush sampler to collect cells for the cytologic diagnosis of NPIN and NPC. If successful, the technique could be used as a screening test in endemic areas. METHODS A disposable sampler (Uterobrush) was used to collect nasopharyngeal mucosal brushings from 546 patients for cytologic examination. After this, most patients had biopsies, and this allowed histologic-cytologic correlation to be undertaken. RESULTS In 528 patients (96.7%) there were satisfactory cytologic and biopsy specimens for evaluation. There were 149 cases with positive histology and 103 had positive cytology (specificity was 100% and the sensitivity was 69.1%). One case of NPC with concurrent NPIN was seen among the biopsy specimens, but no case of NPIN was detected cytologically. CONCLUSIONS The cytologic pickup of NPC was substantially lower than that obtained on biopsy. More importantly, NPIN was uncommon. Therefore, a screening test that depends on the collection of cells for the microscopic diagnosis of NPIN and NPC is unlikely to have a major impact on the incidence of NPC. Furthermore, obtaining a good cytologic specimen from the nasopharynx is not simple, and this further limits this technique for mass screening purposes. The concept of a cytologic test for NPC, similar to the Pap test for the prevention of uterine cervix cancer, has still to be realized.
Collapse
Affiliation(s)
- A R Chang
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong, S.A.R., China
| | | | | | | | | | | |
Collapse
|
44
|
Payra P, Hung SC, Kwok WH, Johnston D, Gallucci J, Chan MK. Structural, magnetic and catalytic properties of a self-recognized mu-oxo-bridged diiron(III) bis(benzimidazole) complex. Inorg Chem 2001; 40:4036-9. [PMID: 11466065 DOI: 10.1021/ic0013781] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The inherent nonplanarity and C(2) symmetry of the dimethyl-substituted bis(benzimidazole) ligand (Me(2)BBZ) results in two distinct atropisomers that, when separated, have been suggested to have potential for chiral recognition and catalysis. Here is reported the synthesis and characterization of a diiron mu-oxo-bridged bis(benzimidazole) complex, 1, that provides indirect support for this hypothesis. Dimerization of a racemic solution of iron-Me(2)BBZ monomers via the mu-oxo bridge yields (+,+) and (-,-) diastereomers whose complementary association can be attributed to the inherent sidedness of the metal-Me(2)BBZ interaction surface, and to the differences in the torsional angles of the phenyl(benzimidazole) units (34 degrees) and the Schiff base linkages (54 degrees). These results highlight the steric differences between the phenyl(benzimidazole) and Schiff-base portions of the ligand, features that could be important in the chiral recognition of ligands and in differentiating substrate trajectories as required for asymmetric catalysis. For completeness, studies of 1 in the catalytic epoxidation of styrene are also reported.
Collapse
Affiliation(s)
- P Payra
- Department of Chemistry, The Ohio State University, Columbus, OH 43210, USA
| | | | | | | | | | | |
Collapse
|
45
|
Marenstein DR, Ocampo MT, Chan MK, Altamirano A, Basu AK, Boorstein RJ, Cunningham RP, Teebor GW. Stimulation of human endonuclease III by Y box-binding protein 1 (DNA-binding protein B). Interaction between a base excision repair enzyme and a transcription factor. J Biol Chem 2001; 276:21242-9. [PMID: 11287425 DOI: 10.1074/jbc.m101594200] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human endonuclease III (hNth1) is a DNA glycosylase/apurinic/apyrimidinic (AP) lyase that initiates base excision repair of pyrimidines modified by reactive oxygen species, ionizing, and ultraviolet radiation. Using duplex 2'-deoxyribose oligonucleotides containing an abasic (AP) site, a thymine glycol, or a 5-hydroxyuracil residue as substrates, we found the AP lyase activity of hNth1 was 7 times slower than its DNA glycosylase activity, similar to results reported for murine and human 8-oxoguanine-DNA glycosylase, which are also members of the endonuclease III family. This difference in rates contrasts with the equality of rates found in Escherichia coli and Saccharomyces cerevisiae endonuclease III homologs. A yeast two-hybrid screen for potential modulators of hNth1 activity revealed interaction with the damage-inducible transcription factor Y box-binding protein 1 (YB-1), also identified as DNA-binding protein B (DbpB). The in vitro addition of His(6)YB-1 to hNth1 increased the rate of DNA glycosylase and AP lyase activity. Analysis revealed that YB-1 affects the steady state equilibrium between the covalent hNth1-AP site Schiff base ES intermediate and the noncovalent ES intermediate containing the AP aldehydic sugar and the epsilon-amino group of the hNth1 active site lysine. This equilibrium may be a checkpoint in modulating hNth1 activity.
Collapse
Affiliation(s)
- D R Marenstein
- Department of Pathology and Kaplan Comprehensive Cancer Center, New York University School of Medicine, New York, New York 10016, USA
| | | | | | | | | | | | | | | |
Collapse
|
46
|
Kwok PC, Chung TK, Chong LC, Chan SC, Wong WK, Chan MK, Chu WS. Neurologic injury after endovascular stent-graft and bilateral internal iliac artery embolization for infrarenal abdominal aortic aneurysm. J Vasc Interv Radiol 2001; 12:761-3. [PMID: 11389230 DOI: 10.1016/s1051-0443(07)61450-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The authors report a rare neurologic complication after the implantation of a bifurcated stent-graft for abdominal aortic aneurysm. The stent-graft was extended to both external iliac arteries after embolization of both internal iliac arteries. The patient subsequently had weakness and numbness of both lower limbs with bowel and bladder incontinence. He probably had ischemic injury to the nerve roots or the lumbosacral plexus, which was related to extensive occlusion of their supplying arteries. The mechanism of spinal cord and neurologic ischemia after aortic stent-graft implantation is discussed.
Collapse
Affiliation(s)
- P C Kwok
- Department of Radiology and Imaging, Queen Elizabeth Hospital, 30 Gascoigne Road, Kowloon, Hong Kong.
| | | | | | | | | | | | | |
Collapse
|
47
|
Arndt JW, Gong W, Zhong X, Showalter AK, Liu J, Dunlap CA, Lin Z, Paxson C, Tsai MD, Chan MK. Insight into the catalytic mechanism of DNA polymerase beta: structures of intermediate complexes. Biochemistry 2001; 40:5368-75. [PMID: 11330999 DOI: 10.1021/bi002176j] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The catalytic reaction mediated by DNA polymerases is known to require two Mg(II) ions, one associated with dNTP binding and the other involved in metal ion catalysis of the chemical step. Here we report a functional intermediate structure of a DNA polymerase with only one metal ion bound, the DNA polymerase beta-DNA template-primer-chromium(III).2'-deoxythymidine 5'-beta,gamma-methylenetriphosphate [Cr(III).dTMPPCP] complex, at 2.6 A resolution. The complex is distinct from the structures of other polymerase-DNA-ddNTP complexes in that the 3'-terminus of the primer has a free hydroxyl group. Hence, this structure represents a fully functional intermediate state. Support for this contention is provided by the observation of turnover in biochemical assays of crystallized protein as well as from the determination that soaking Pol beta crystals with Mn(II) ions leads to formation of the product complex, Pol beta-DNA-Cr(III).PCP, whose structure is also reported. An important feature of both structures is that the fingers subdomain is closed, similar to structures of other ternary complexes in which both metal ion sites are occupied. These results suggest that closing of the fingers subdomain is induced specifically by binding of the metal-dNTP complex prior to binding of the catalytic Mg(2+) ion. This has led us to reevaluate our previous evidence regarding the existence of a rate-limiting conformational change in Pol beta's reaction pathway. The results of stopped-flow studies suggest that there is no detectable rate-limiting conformational change step.
Collapse
Affiliation(s)
- J W Arndt
- Departments of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Chiu CY, Wong WK, Mak HL, Chan CS, Kwok CH, Chan CH, Chan MK. Uterine artery embolisation for treatment of fibroids: experience in Chinese women. Singapore Med J 2001; 42:148-54. [PMID: 11465313] [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: 02/20/2023]
Abstract
Twelve women with symptomatic fibroids were treated with transcatheter uterine artery embolisation with the use of polyvinyl alcohol (PVA) particles. For the nine women who were due for follow-up, reduction in uterine volume and dominant fibroid size were observed on magnetic resonance imaging. All the nine women had normal luteinising hormone (LH) and follicle stimulating hormone (FSH) levels before the procedure and during the follow-up. Seven of the nine women reported noticeable symptomatic improvement during the follow-up. Pain experienced was of variable level, but well controlled. Adequate analgesia is essential for the procedure. Longer follow-up and prospective fertility studies are required to evaluate the long-term effects before this procedure could be safely extended to younger age groups.
Collapse
Affiliation(s)
- C Y Chiu
- Department of Radiology and Imaging, Queen Elizabeth Hospital, Kowloon, Hong Kong.
| | | | | | | | | | | | | |
Collapse
|
49
|
Abstract
In recent years, an increasing number of proteins have been discovered which utilize heme cofactors to sense oxygen, carbon monoxide and nitric oxide. The identification and characterization of these proteins are revising our understanding of heme-mediated allostery first established in the early 1960s. Biochemical and structural studies are revealing new mechanisms for heme-driven conformational changes distinct from the classical hemoglobin model.
Collapse
Affiliation(s)
- M K Chan
- Departments of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210-1173, USA.
| |
Collapse
|
50
|
Abstract
The association of cardiac malformation with the congenital nephrotic syndrome (CNS) has been previously reported in only one family. We report four patients with CNS: three with pulmonary valve stenosis (one requiring valvuloplasty) and one with discrete subaortic stenosis requiring surgical resection. We conclude that the cardiac status of all patients with CNS should be reviewed regularly by a paediatrician, with a low threshold for referral to a cardiologist, as flow murmurs due to chronic anaemia may obscure cardiac pathology. It is important to diagnose any associated cardiac lesions as these may require intervention, and may also predispose to the development of bacterial endocarditis if surgical or dental procedures are undertaken without appropriate antibiotic prophylaxis.
Collapse
Affiliation(s)
- V Grech
- Department of Paediatrics, St Luke's Hospital, Guardamangia, Malta.
| | | | | | | | | | | |
Collapse
|