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Chan VWS, Rahman L, Ng HHL, Tang KP, Mok A, Tang A, Liu JPH, Ho KSC, Chan SM, Wong S, Teoh AYB, Chan A, Wong MCS, Yuan Y, Teoh JYC. Mitigation of COVID-19 transmission in endoscopic and surgical aerosol-generating procedures: a narrative review of early-pandemic literature. Hong Kong Med J 2023. [PMID: 37217445 DOI: 10.12809/hkmj209089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023] Open
Affiliation(s)
- V W S Chan
- School of Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom
| | - L Rahman
- School of Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom
| | - H H L Ng
- School of Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom
| | - K P Tang
- Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - A Mok
- Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - A Tang
- School of Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom
| | - J P H Liu
- Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - K S C Ho
- Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - S M Chan
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - S Wong
- Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - A Y B Teoh
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - A Chan
- Department of Anaesthesia and Intensive Care, Prince of Wales Hospital, Hong Kong SAR, China
| | - M C S Wong
- The Jockey Club School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Y Yuan
- Department of Medicine, McMaster University, Hamilton, Canada
| | - J Y C Teoh
- SH Ho Urology Centre, Department of Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
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Mak J, Chan SM, Siu B, Lai J, Wong V. Hepatobiliary and Pancreatic: A tree in the liver. J Gastroenterol Hepatol 2021; 36:2337. [PMID: 34318507 DOI: 10.1111/jgh.15623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/02/2021] [Accepted: 07/05/2021] [Indexed: 12/09/2022]
Affiliation(s)
- Jwy Mak
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong
| | - S M Chan
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong
| | - Bmk Siu
- Department of Anaesthesia and Intensive Care, Princes of Wales Hospital, Hong Kong
| | - Jct Lai
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong
| | - Vws Wong
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong
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Yau KC, Chan SM. Psychometric Properties of the Traditional Chinese Version of the Child and Adolescent Needs and Strengths-Trauma Comprehensive. East Asian Arch Psychiatry 2021; 31:36-42. [PMID: 34987116 DOI: 10.12809/eaap1967] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
OBJECTIVE To determine the internal consistency, construct validity, and scaling properties of the traditional Chinese version of the Child and Adolescent Needs and Strengths-Trauma Comprehensive (TC-CANS-Trauma). METHODS 66 male and 62 female children, adolescents, and young adults aged 3 to 22 years who were referred to trauma treatment service were selected by convenience sampling. The original English version of the CANS-Trauma was translated to traditional Chinese by a medical professional, back-translated to English by a clinical psychologist, and then cross-checked by another psychologist to ensure consistency. Chinese wordings were adjusted to maintain the conceptual rather than literal meaning. Participants were assessed using the TC-CANS-Trauma as well as the traditional Chinese version of the Life Events Checklist (LEC), the Children's Impact of Event Scale-Revised (CHIES-R), the Strengths and Difficulties Questionnaire-Impact Component (SDQ-Impact), and the Parenting Sense of Competence (PSOC). Internal consistency of eight primary domains of the TC-CANS-Trauma was evaluated by Cronbach's alpha. Construct (convergent and divergent) validity of five of these domains with the LEC, the CHIES-R, the SDQ-Impact, and the PSOC was assessed. Rasch modelling was used to evaluate the scaling properties of the eight primary domains of the TC-CANS-Trauma. RESULTS Internal consistency of the eight primary domains of the TC-CANS-Trauma was satisfactory, with Cronbach's alpha ranging from 0.63 to 0.90. Construct (convergent and divergent) validity of five of these domains with the LEC, the CHIES-R, the SDQ-Impact, and the PSOC was good. In Rasch modelling, most TC-CANS-Trauma domains showed good item separation values. Infit and outfit statistics of most domain items were <2 indicating good item fitness in their respective domains. For person separation, all domains of the TC-CANS-Trauma did not have a sufficient discriminability to identify high and low performers. CONCLUSIONS The TC-CANS-Trauma is valid for comprehensive assessment of trauma-related domains among Hong Kong children and adolescents. Its ratings can be used to guide the levels of clinical intervention required. Clinicians are recommended to implement the TC-CANS-Trauma to facilitate trauma-informed practice in Hong Kong.
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Affiliation(s)
- K C Yau
- Jockey Club Trauma Treatment Service for Children, The Boys' & Girls' Clubs Association of Hong Kong
| | - S M Chan
- Jockey Club Trauma Treatment Service for Children, The Boys' & Girls' Clubs Association of Hong Kong
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Ji XW, Chan HY, Chan LW, Chan SM. 1100 DAYTIME FUNCTION IN MIND-BODY TREATMENT OF COCURRENT SLEEP AND MOOD DISTURBANCES. Sleep 2017. [DOI: 10.1093/sleepj/zsx050.1099] [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: 11/14/2022] Open
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Heath EM, Chan SM, Minden MD, Murphy T, Shlush LI, Schimmer AD. Biological and clinical consequences of NPM1 mutations in AML. Leukemia 2017; 31:798-807. [PMID: 28111462 DOI: 10.1038/leu.2017.30] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 01/09/2017] [Accepted: 01/13/2017] [Indexed: 12/16/2022]
Abstract
Acute myeloid leukemia (AML) is characterized by accumulation of myeloid cells in the bone marrow because of impaired differentiation and proliferation, resulting in hematopoietic insufficiency. NPM1 is one of the most commonly mutated genes in AML, present in 20-30% of cases. Mutations in NPM1 represent a distinct entity in the World Health Organization (WHO) classification and commonly indicate a better risk prognosis. In this review, we discuss the many functions of NPM1, the consequence of mutations in NPM1 and possible mechanisms through which mutations lead to leukemogenesis. We also discuss clinical consequences of mutations, associated gene expression patterns and the role of NPM1 mutations in informing prognosis and therapeutic decisions and predicting relapse in AML.
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Affiliation(s)
- E M Heath
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Ontario, Canada
| | - S M Chan
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - M D Minden
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Ontario, Canada
| | - T Murphy
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Ontario, Canada
| | - L I Shlush
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.,Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - A D Schimmer
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Ontario, Canada
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Ng TP, Nyunt MSZ, Feng L, Feng L, Niti M, Tan BY, Chan G, Khoo SA, Chan SM, Yap P, Yap KB. Multi-Domains Lifestyle Interventions Reduces Depressive Symptoms among Frail and Pre-Frail Older Persons: Randomized Controlled Trial. J Nutr Health Aging 2017; 21:918-926. [PMID: 28972245 DOI: 10.1007/s12603-016-0867-y] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND We investigated the effect of multi-domain lifestyle (physical, nutritional, cognitive) interventions among frail and pre-frail community-living older persons on reducing depressive symptoms. METHOD Participants aged 65 and above were randomly allocated to 24 weeks duration interventions with nutritional supplementation (N=49), physical training (N=48), cognitive training (N=50), combination intervention (N=49) and usual care control (N=50). Depressive symptoms were assessed by the Geriatric Depression Scale (GDS-15) at baseline (0M), 3 month (3M), 6 month (6M) and 12 month (12M). RESULTS Mean GDS scores in the control group increased from 0.52 (0M) and 0.54 (3M) to 0.74 (6M), and 0.83 (12M). Compared to the control group, interventions showed significant differences (∆=change) at 6M for cognitive versus control (∆=-0.39, p=0.021, group*time interaction p=0.14); physical versus control (∆ =-0.37, p=0.026, group*time interaction p=0.13), and at 12M for nutrition versus control (∆ =-0.46, p=0.016, group*time interaction p=0.15). The effect for combination versus control was significant at 6M (∆ =-0.43, p=0.020) and 12M (∆ =-0.51, p=0.005, group*time interaction p=0.026). Estimated 12-month cumulative incidence of depressive symptoms (GDS≥2) relative to control were OR=0.38, p=0.037 (nutrition); OR=0.71, p=0.40 (cognitive); OR=0.39, p=0.042 (physical training) and OR=0.38, p=0.037 (combination). Changes in gait speed and energy level were significantly associated with changes in GDS scores over time. CONCLUSION Multi-domain interventions that reverse frailty among community-living older persons also reduce depressive symptomatology. Public health education and programmatic measures combining nutritional, physical and cognitive interventions for at-risk frail older people may likely benefit psychological wellbeing.
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Affiliation(s)
- T P Ng
- A/P Tze-Pin Ng, Gerontology Research Programme, National University of Singapore, Department of Psychological Medicine, NUHS Tower Block, 9th Floor, 1E Kent Ridge Road, Singapore 119228 Fax: 65-67772191, Tel: 65-67723478
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Medeiros BC, Fathi AT, DiNardo CD, Pollyea DA, Chan SM, Swords R. Isocitrate dehydrogenase mutations in myeloid malignancies. Leukemia 2016; 31:272-281. [PMID: 27721426 PMCID: PMC5292675 DOI: 10.1038/leu.2016.275] [Citation(s) in RCA: 246] [Impact Index Per Article: 30.8] [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: 06/28/2016] [Revised: 08/17/2016] [Accepted: 08/25/2016] [Indexed: 12/14/2022]
Abstract
Alterations to genes involved in cellular metabolism and epigenetic regulation are implicated in the pathogenesis of myeloid malignancies. Recurring mutations in isocitrate dehydrogenase (IDH) genes are detected in approximately 20% of adult patients with acute myeloid leukemia (AML) and 5% of adults with myelodysplastic syndromes (MDS). IDH proteins are homodimeric enzymes involved in diverse cellular processes, including adaptation to hypoxia, histone demethylation and DNA modification. The IDH2 protein is localized in the mitochondria and is a critical component of the tricarboxylic acid (also called the ‘citric acid' or Krebs) cycle. Both IDH2 and IDH1 (localized in the cytoplasm) proteins catalyze the oxidative decarboxylation of isocitrate to α-ketoglutarate (α-KG). Mutant IDH enzymes have neomorphic activity and catalyze reduction of α-KG to the (R) enantiomer of 2-hydroxyglutarate, which is associated with DNA and histone hypermethylation, altered gene expression and blocked differentiation of hematopoietic progenitor cells. The prognostic significance of mutant IDH (mIDH) is controversial but appears to be influenced by co-mutational status and the specific location of the mutation (IDH1-R132, IDH2-R140, IDH2-R172). Treatments specifically or indirectly targeted to mIDH are currently under clinical investigation; these therapies have been generally well tolerated and, when used as single agents, have shown promise for inducing responses in some mIDH patients when used as first-line treatment or in relapsed or refractory AML or MDS. Use of mIDH inhibitors in combination with drugs with non-overlapping mechanisms of action is especially promising, as such regimens may address the clonal heterogeneity and the multifactorial pathogenic processes involved in mIDH myeloid malignancies. Advances in mutational analysis have made testing more rapid and convenient, and less expensive; such testing should become part of routine diagnostic workup and repeated at relapse to identify patients who may benefit from treatments that target mIDH.
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Affiliation(s)
- B C Medeiros
- Division of Hematology, Department of Medicine, Stanford University School of Medicine, Stanford Cancer Center, Stanford, CA, USA
| | - A T Fathi
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
| | - C D DiNardo
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - D A Pollyea
- Division of Hematology, University of Colorado School of Medicine, Aurora, CO, USA
| | - S M Chan
- Princess Margaret Cancer Centre, Toronto, ON, Canada
| | - R Swords
- Sylvester Comprehensive Cancer Center, University of Miami, Miami, FL, USA
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Weber U, Zubler V, Zhao Z, Lambert RG, Chan SM, Pedersen SJ, Ostergaard M, Maksymowych WP. OP0273 Does Spinal MRI Add Incremental Diagnostic Value to MRI of the Sacroiliac Joints Alone in Non-Radiographic Axial Spondyloarthritis? Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2013-eular.478] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Weber U, Zubler V, Zhao Z, Lambert RG, Rufibach K, Chan SM, Pedersen SJ, Ostergaard M, Maksymowych WP. SAT0227 Low Diagnostic Utility Of Candidate Definitions for a Positive MRi of the Spine in Axial Spondyloarthritis. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2013-eular.1953] [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: 11/04/2022]
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Weber U, Zhao Z, Zubler V, Chan SM, Lambert RG, Ostergaard M, Pedersen SJ, Maksymowych WP. OP0217 Frequent Detection of Inflammation and Fat Infiltration Suggestive of Spondyloarthritis on MRI of the Entire Spine in Healthy Subjects and Patients with Mechanical Back Pain. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2013-eular.422] [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: 11/03/2022]
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Chan SM, Chiu PWY, Wu JCY, Kwan SM, Kwong PY, Lam KW, Lo KK, Tee MKM, Wong CP, Teoh AYB, Wong SKH, Ng EKW. Laparoscopic Heller's cardiomyotomy achieved lesser recurrent dysphagia with better quality of life when compared with endoscopic balloon dilatation for treatment of achalasia. Dis Esophagus 2013; 26:231-6. [PMID: 22624653 DOI: 10.1111/j.1442-2050.2012.01357.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Achalasia is a rare primary motility disorder of esophagus; treatments include endoscopic balloon dilatation (EBD) and laparoscopic Heller's cardiomyotomy (LC). This study compared EBD versus LC for treatment of achalasia with focus on quality of life (QoL) and prevalence of post-treatment gastroesophageal reflux disease. This was a retrospective cohort study of all patients diagnosed with achalasia older than 16 treated with either EBD or LC from January 1998 to April 2008. Patients' demographic data, comorbidities, postintervention GERD symptoms, QoL, recurrence of dysphagia, reintervention rate, hospital stay, and time to resumption of diet were collected. Sixty-eight patients were recruited into the study (EBD n= 50; LC n= 18). A significant improvement in QoL was found in patients undergoing LC (0.917 vs. 0.807, P= 0.006). A higher proportion of patients treated with EBD developed post-treatment gastroesophageal reflux symptoms (60.5% vs. 43.8%) when compared with LC, although statistically insignificant (P= 0.34). Patients treated with balloon dilatation had a greater percentage of recurrence of dysphagia (55.1% vs. 26.7%; P= 0.235) and need of reintervention (42.1% vs. 9.1%; P= 0.045). However, these patients had a shorter median hospital stay (1d [range 0-4]) and earlier resumption of diet (0d [range 0-3]). Although EBD is associated with a quicker perioperative recovery, LC accomplished a better QoL, lower incidence of recurrence of dysphagia, and need of reintervention after treatment for achalasia.
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Affiliation(s)
- S M Chan
- Department of Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
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Abstract
BACKGROUND Shyness in late childhood is related to social and psychological problems. The present study examined the relations among shyness, attributional styles and self-esteem. It was hypothesized that self-esteem mediated the effects of attributional styles on shyness. METHODS Self-reported data on degree of shyness, attributional styles and self-esteem were obtained from 326 Chinese children with mean age of 10.85 years. RESULTS It was found that positive attributional styles predicted shyness in the negative direction and the effects were fully mediated by self-esteem, and negative attributional styles predicted shyness in the positive direction both directly and through self-esteem. CONCLUSION The results imply that how children attribute positive and negative outcomes affect both self-esteem and shyness. It is suggested that practitioners should conduct attribution-retraining workshops for shy children and help teachers and parents learn how to mitigate negative attributional style and foster positive attributional styles in children.
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Affiliation(s)
- S M Chan
- Department of Psychological Studies, Hong Kong Institute of Education, Hong Kong, China
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Chan SM. Social competence of elementary-school children: relationships to maternal authoritativeness, supportive maternal responses and children's coping strategies. Child Care Health Dev 2011; 37:524-32. [PMID: 21276033 DOI: 10.1111/j.1365-2214.2010.01196.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Although the influences of parenting on children's development of social competence have been well established, research on the underlying mechanisms of this link is relatively limited. The present study examined children's coping strategies as a mediator of the effects of maternal authoritativeness and maternal inductive responses on their social competence. METHOD The mothers of 183 Hong Kong Chinese children aged 6 to 8 years (89 girls and 94 boys) reported on their adoption of authoritative parenting and their responses to their children's expressions of emotion, and rated their children's adoption of constructive coping strategies. The children's teachers reported on the children's prosocial behaviour, and rated their level of peer acceptance at school. RESULTS A model of maternal authoritativeness and supportive maternal responses affecting children's social competence is presented. The study results show that the effects of authoritative parenting on children's adoption of constructive coping strategies were mediated by supportive maternal responses to children's expression of emotion, and that the effects of maternal authoritativeness and maternal responses on children's social competence were mediated by children's coping strategies. These results suggest that school personnel should organize training programmes on emotion-coping strategies for both parents and children. CONCLUSION The findings imply that positive parenting facilitates children's acquisition of constructive emotion-coping strategies. Programmes on emotion-coping strategies should be introduced for both parents and school children.
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Affiliation(s)
- S M Chan
- Department of Psychological Studies, Hong Kong Institute of Education, Hong Kong, China.
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Chan SM, Garcia FJ, Chin JL, Moussa M, Gabril MY. The clinical significance of in-depth pathological assessment of extraprostatic extension and margin status in radical prostatectomies for prostate cancer. Prostate Cancer Prostatic Dis 2011; 14:307-12. [DOI: 10.1038/pcan.2011.15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Paniagua RT, Sharpe O, Ho PP, Chan SM, Chang A, Higgins JP, Tomooka BH, Thomas FM, Song JJ, Goodman SB, Lee DM, Genovese MC, Utz PJ, Steinman L, Robinson WH. Selective tyrosine kinase inhibition by imatinib mesylate for the treatment of autoimmune arthritis. J Clin Invest 2006. [DOI: 10.1172/jci28546.] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Tse K, Siu SLY, Yip KT, Chan SM, Que TL, Lui WYS, Chan PS. Immuno-prophylaxis of babies borne to hepatitis B carrier mothers. Hong Kong Med J 2006; 12:368-74. [PMID: 17028357] [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
OBJECTIVES To examine the efficacy of current hepatitis B immuno-prophylaxis and estimate the prevalence of S-mutant infections among local newborn babies. DESIGN Prospective study. SETTING Regional hospital, Hong Kong. PATIENTS A total of 137 newborn babies delivered between the period of November 2000 and 30 June 2001 inclusive, whose mothers were chronic hepatitis B surface antigen carriers. RESULTS Of the 121 infants who were followed up for 12 months, three were found to be chronic hepatitis B virus carriers, giving a vertical transmission rate of 2.5%. One (0.8%) was suspected to be infected by the S-mutant. All the three hepatitis B virus carrier babies were born to mothers with hepatitis B e antigen, but none to the eight mothers suspected to have S-mutants. Of 119 (98.3%) infants who developed hepatitis B surface antibody upon follow-up at 12 months, 35 were found to have hepatitis B e antigen at birth. All were born to hepatitis B e antigen-positive mothers. Only three of the 35 babies were found to be hepatitis B virus carriers. Most babies lost the hepatitis B e antigen by 6 months of age; only the infected babies had the antigen persisting at 1 year of age. The non-infected infants' hepatitis B e antigen is likely transplacental. CONCLUSIONS Our hepatitis B virus prophylaxis programme was effective at preventing perinatal infection and the non-infected infants' hepatitis B e antigen was likely transplacental.
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Affiliation(s)
- K Tse
- Department of Paediatrics and Adolescent Medicine, Tuen Mun Hospital, Tsing Chung Koon Road, Tuen Mun, Hong Kong
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Chan SM, Basmadjian GP, Marten DF, Sadek SA, Magarian RA, Grunder JR, Ice RD. Synthesis and biodistribution of radioiodinated-5-iodonicotine. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.2580200813] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [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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Ni IH, Chan SM, Wang WX. Influences of salinity on the biokinetics of Cd, Se, and Zn in the intertidal mudskipper Periophthalmus cantonensis. Chemosphere 2005; 61:1607-17. [PMID: 15979689 DOI: 10.1016/j.chemosphere.2005.04.090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Revised: 04/13/2005] [Accepted: 04/18/2005] [Indexed: 05/03/2023]
Abstract
The biokinetics (aqueous uptake, dietary assimilation, and elimination) of Cd, Se, and Zn in the intertidal mudskipper, Periophthalmus cantonensis, were examined at different acclimated salinities using the radiotracer technique. The dietary assimilation efficiency from ingested radiolabeled polychaetes was the highest for Se (32-40%), followed by Zn (5-7%) and Cd (2-3%), and was not influenced by salinity within a range of 10-30 psu. Uptake from the dissolved phase typically exhibited a linear pattern within the first 12 h of exposure, followed by a second slower uptake. The highest concentration factor (CF) was found for Zn, followed by Cd and Se. Differences in salinity did not significantly affect the CF of the three metals within the first 12 h, but the CFs were significantly higher at lower salinities (10-20 psu) than at the highest salinity (30 psu) by the end of 48 h exposure. Because the degrees to which the uptake of Se (a metalloid) and Cd/Zn were affected by salinity were comparable, we concluded that metal speciation as a result of salinity change was not important in leading to a change in metal CF. Physiological changes may be responsible for the increasing uptake at lowered salinity. The elimination rates of the three metals (0.01-0.06 d(-1)) were not significantly affected by salinity, but Se was eliminated at a faster rate following aqueous uptake than following dietary ingestion. There was no consistent influence of exposure routes on Cd and Zn elimination. The accumulated Cd was mainly associated with the gut, whereas the muscle was the dominant target site for Se and Zn accumulation.
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Affiliation(s)
- I-Hsun Ni
- Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Keelung 20224, Taiwan
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Chan SM, Nelson EAS, Leung SSF, Cheng JCY. Bone mineral density and calcium metabolism of Hong Kong Chinese postpartum women—a 1-y longitudinal study. Eur J Clin Nutr 2005; 59:868-76. [PMID: 15915158 DOI: 10.1038/sj.ejcn.1602148] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [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
OBJECTIVE This paper reports longitudinal changes in bone mineral density (BMD), calcium homeostasis and dietary calcium intake in a group of Hong Kong breastfeeding women during the first year postpartum. DESIGN AND SUBJECTS Nine mothers who breastfed exclusively or almost exclusively for at least 3 months and 14 formula feeding mothers aged 20-40 y were interviewed after delivery, 2 and 6 weeks, 3, 6 and 12 months postpartum. BMD at L2-L4 lumbar spine (LS), trochanter (Tro) and femoral neck (FN), serum intact parathyroid hormone (iPTH), serum bone-specific alkaline phosphatase (b-ALP), urinary deoxypyridinoline (Dpd), serum and urinary calcium (Ca) and phosphorus (P) and dietary intake of macronutrients were assessed. RESULTS Compared to the formula feeding group, BMD assessed at LS, Tro and FN decreased significantly in the breastfeeding group over the first 6 months, with rebound to approximate baseline values at 12 months for the latter two sites. Serum iPTH increased in both groups, whereas serum b-ALP was consistently higher in the breastfeeders. Urinary Ca and P excretion decreased early postpartum in both groups, but the breastfeeders had higher excretion at 3 and 6 months. Breastfeeding mothers consumed significantly more Ca than the formula feeding mothers in the early postpartum. CONCLUSIONS Increased calcium requirement during early lactation is affected through mobilisation of bone and renal calcium conservation. Bone mineral loss during lactation is temporary. Further studies are warranted to investigate the effects of diet and other hormonal factors on the calcium homeostasis during lactation.
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Affiliation(s)
- S M Chan
- Department of Paediatrics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
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20
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Kee F, Ng SSM, Vaudry H, Pang RTK, Lau EHY, Chan SM, Chow BKC. Aspartic acid scanning mutation analysis of a goldfish growth hormone-releasing hormone (GHRH) receptor specific to the GHRHsalmon-like peptide. Gen Comp Endocrinol 2005; 140:41-51. [PMID: 15596070 DOI: 10.1016/j.ygcen.2004.09.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [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] [Received: 05/06/2004] [Revised: 08/24/2004] [Accepted: 09/15/2004] [Indexed: 11/22/2022]
Abstract
Growth hormone-releasing hormone (GHRH) plays a pivotal role in the regulation of growth. The study of goldfish GHRH and its receptor is of particular interest as it is so far the only animal model in which two forms of GHRH-like (catfish-like and salmon-like) peptides coexist, and these peptides share only 30-40% of amino acid sequence identities with their mammalian counterparts. For these reasons, we have previously characterized a goldfish GHRH receptor, which is specific for a synthetic carp GHRH-like peptide. In this study, we investigated the structure-function relationships between the receptor and various ligands. Interestingly, among the two endogenous goldfish GHRH-like peptides, only the GHRHsalmon-like peptide was able to stimulate CHO cells transfected with the goldfish GHRH receptor. When the receptor was challenged by GHRHsalmon-like peptide either continuously for 45 min or periodically at 45-min intervals, mild homologous desensitization was observed. To determine whether the negatively charged residues of the receptor are responsible for discriminating GHRHsalmon-like from GHRHcatfish-like, 10 aspartic acid residues residing in the N-terminal ectodomain and the second exoloop were individually mutated to alanine by site-directed mutagenesis. Among these 10 mutants, four of them (D66A, D122A, D190A, and D196A) were defective as indicated by both cAMP assays and extracellular acidification rate measurements. Confocal microscopic studies showed that the D66A and D122A mutants, but not the D190A and D196A mutants, were expressed properly at the plasma membrane. Collectively, these results suggest that aspartic acid residues at positions 66 and 122 are critical for the interaction between the goldfish GHRH receptor and its endogenous ligands.
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Affiliation(s)
- Francis Kee
- Department of Zoology, University of Hong Kong, Hong Kong, PR China
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21
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Yu JC, Chan SM, Chen Z. Preconcentration using diethylenetriaminetetraacetic acid-functionalized polysiloxane (DETAP) for determination of molybdenum(VI) in seawater by ICP-OES. Anal Bioanal Chem 2003; 376:728-34. [PMID: 12802571 DOI: 10.1007/s00216-003-1956-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2003] [Revised: 03/29/2003] [Accepted: 03/31/2003] [Indexed: 10/26/2022]
Abstract
This paper reports a new method for preconcentration and separation of trace amounts of molybdenum in seawater samples prior to determination by inductively coupled plasma-atomic emission spectroscopy (ICP-OES). Diethylenetriaminetetraacetic acid-functionalized polysiloxane (DETAP) was synthesized by carboxymethylation of amino groups on triamine immobilized polymer, which was prepared by modification of 3-chloropropylpolysiloxane with diethylenetriamine. The resulting polysiloxane is highly selective and efficient in chelating Mo(VI) at trace levels. It can be used as a column packing material. The polysiloxane column can be reused over ten times without losing its original properties, so it is suitable for preconcentration of molybdenum species in seawater samples before determination. The parameters governing the characteristics of polysiloxane for adsorption of Mo(VI) were investigated. These include the effect of pH, amount of polysiloxane, equilibrium time, adsorption isotherm, maximum adsorption capacity, interfering ions, flow rate, capacity for reuse, and desorption. The precision of the preconcentration method, calculated as the relative standard deviation of seawater samples, was 3%. The preconcentration factor was 100. The detection limit, defined as 3 times the standard deviation of five replicate measurements of the blank sample at pH 3, was 0.17 microg L(-1). Measurement results for standard reference materials were in good agreement with the certified values [(CRMs), NASS-2 Seawater (Open Ocean) and CASS-2 Seawater (Coastal)].
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Affiliation(s)
- Jimmy C Yu
- Department of Chemistry and Environmental Science Programme, The Chinese University of Hong Kong, Shatin, Hong Kong, New Territories, China.
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22
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Soechitram SD, Chan SM, Nelson EAS, Brouwer A, Sauer PJJ. Comparison of dioxin and PCB concentrations in human breast milk samples from Hong Kong and the Netherlands. Food Addit Contam 2003; 20:65-9. [PMID: 12519720 DOI: 10.1080/0265203021000031528] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The adverse effects of dioxins and polychlorinated biphenyls (PCBs) on human health are of increasing concern. These lipophilic compounds are concentrated through the food chain and are present in human milk. This study compares PCB levels in human milk samples from Hong Kong and Dutch mothers. Ten breast milk samples from Hong Kong and 10 from the Netherlands were collected during home visits between 2 and 6 weeks postpartum. Total toxic equivalence (TEQ) of dioxin and PCBs were determined using the DR-CALUX(R) bioassay. The total dioxin and PCB levels in breast milk samples for Hong Kong ranged from 3.1 to 29.9 pg TEQ g(-1) lipid and for the Netherlands from 8.9 to 89.5 pg TEQ g(-1) lipid. Despite Hong Kong's high degree of industrialization, the levels of dioxin and PCBs were fourfold lower in the Hong Kong than in the Dutch samples. This may be due to a lower dietary intake of dioxins and PCBs in Hong Kong because of lower background levels of these contaminants or to different food habits.
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Affiliation(s)
- S D Soechitram
- Department of Paediatrics, University Hospital, Groningen, The Netherlands
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23
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He JG, Deng M, Weng SP, Li Z, Zhou SY, Long QX, Wang XZ, Chan SM. Complete genome analysis of the mandarin fish infectious spleen and kidney necrosis iridovirus. Virology 2001; 291:126-39. [PMID: 11878882 DOI: 10.1006/viro.2001.1208] [Citation(s) in RCA: 177] [Impact Index Per Article: 7.7] [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]
Abstract
The nucleotide sequence of the infectious spleen and kidney necrosis virus (ISKNV) genome was determined and found to comprise 111,362 bp with a G+C content of 54.78%. It contained 124 potential open reading frames (ORFs) with coding capacities ranging from 40 to 1208 amino acids. The analysis of the amino acid sequences deduced from the individual ORFs revealed that 35 of the 124 potential gene products of ISKNV show significant homology to functionally characterized proteins of other species. Some of the putative gene products of ISKNV showed significant homologies to proteins in the GenBank/EMBL/DDBJ databases including enzymes and structural proteins involved in virus replication, transcription, protein modification, and virus-host interaction. In addition, one major repeated sequence showing significant homology to the Red Sea bream iridovirus (RSIV) genome was identified. Based on the information obtained from biological properties (including histopathology, tissue tropisms, natural host range, and geographic distribution), physiochemical and physical properties, and genome analysis, we suggest that ISKNV, RSIV, sea bass iridovirus, grouper iridovirus, and African lampeye iridovirus may belong to a new genus of the Iridoviridae family and are tentatively referred to as cell hypertrophy iridoviruses.
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Affiliation(s)
- J G He
- State Key Laboratory for Biocontrol, Zhongshan University, Guangzhou, 510275, PR China.
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24
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Silva Gunawardene YI, Chow BK, He JG, Chan SM. The shrimp FAMeT cDNA is encoded for a putative enzyme involved in the methylfarnesoate (MF) biosynthetic pathway and is temporally expressed in the eyestalk of different sexes. Insect Biochem Mol Biol 2001; 31:1115-1124. [PMID: 11520690 DOI: 10.1016/s0965-1748(01)00060-1] [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] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Methylfarnesoate (MF), an analogue of the insect juvenile hormone III, has been implicated to play a vital role in the regulation of the growth and reproductive development in crustaceans. Farnesoic acid O-methyltransferase (FAMeT) is the key enzyme involved in catalyzing the final step in the MF biosynthetic pathway. In this study, we report the cloning and characterization of the cDNA encoding the putative FAMeT of the shrimp Metapenaeus ensis. FAMeT comprises 280 amino acid residues with a predicted molecular weight of 32kDa. The predicted putative FAMeT protein reveals a high degree of structural conservation of FAMeT with the lobsters. It shares 79 and 70% sequence identities with the putative FAMeTs of Homarus americanus and Panulirus interruptus, respectively. As revealed by the Southern blot analysis and genomic PCR, only one gene exists in the shrimp genome and the gene is uninterrupted in the coding region. The shrimp FAMeT mRNA is widely distributed in many tissues with the highest expression level observed in the central nervous system. A constant level of FAMeT expression is recorded in the ventral nerve cord of the juveniles and the mature females during the reproductive cycle. Unlike the ventral nerve cord, the eyestalk of the juvenile male, but not the female, expresses FAMeT. Further study shows that the eyestalk of the mature female expresses FAMeT during all stages of ovarian maturation. We speculate that FAMeT may be important for the regulation of eyestalk neuropeptides. This is the first extensive study on the molecular characterization, structural analysis and expression of the crustacean FAMeT.
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Affiliation(s)
- Y I Silva Gunawardene
- Department of Zoology, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
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25
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Hoo RL, Alexandre D, Chan SM, Anouar Y, Pang RT, Vaudry H, Chow BK. Structural and functional identification of the pituitary adenylate cyclase-activating polypeptide receptor VPAC2 from the frog Rana tigrina rugulosa. J Mol Endocrinol 2001; 27:229-38. [PMID: 11564605 DOI: 10.1677/jme.0.0270229] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [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: 11/27/2022]
Abstract
Recently, a frog pituitary adenylate cyclase-activating polypeptide (PACAP)/vasoactive intestinal peptide (VIP) receptor (fPVR) has been characterized, and interestingly, this receptor exhibits characteristics of both mammalian PACAP type II receptors VPAC(1)R and VPAC(2)R. In order to investigate the receptors responsible for mediating the actions of VIP and PACAP in amphibians, in this report, a frog VPAC(2) receptor (fVPAC(2)R) cDNA was isolated. fVPAC(2)R shares 47.7, 46.9 and 62.5% amino acid sequence identity with fPVR, human VPAC(1)R and human VPAC(2)R respectively. Functionally, fVPAC(2)R, when expressed in CHO cells, was responsive to both frog peptides including VIP, PACAP38 and PACAP27 where the EC(50) values of these peptides in intracellular cAMP production were 0.15, 0.18 and 0.16 microM respectively. The pharmacological profiles of human peptides (VIP, PACAP38 and peptide histidine methionine) to stimulate frog and human VPAC(2)Rs were compared, and it was found that these peptides could only activate the frog receptor at micromolar concentrations. fVPAC(2)R was found to be widely distributed in various peripheral tissues as well as several regions of the brain. The presence of the receptor transcripts suggests the functional roles of the receptor in mediating the actions of PACAP and/or VIP in these tissues. As VIP and particularly PACAP27 are highly conserved peptides in vertebrate evolution, comparative studies of these peptides and their receptors in non-mammalian vertebrates should provide clues to better understand the physiology of these important peptides in human and other vertebrates.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- CHO Cells
- Cricetinae
- Cyclic AMP/biosynthesis
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- Humans
- Molecular Sequence Data
- Neuropeptides/metabolism
- Phylogeny
- Pituitary Adenylate Cyclase-Activating Polypeptide
- Pituitary Gland/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Ranidae/genetics
- Ranidae/metabolism
- Receptors, Vasoactive Intestinal Peptide/chemistry
- Receptors, Vasoactive Intestinal Peptide/genetics
- Receptors, Vasoactive Intestinal Peptide/metabolism
- Receptors, Vasoactive Intestinal Peptide, Type II
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Sequence Homology, Amino Acid
- Species Specificity
- Tissue Distribution
- Vasoactive Intestinal Peptide/metabolism
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Affiliation(s)
- R L Hoo
- Department of Zoology, University of Hong Kong, Pokfulam Road, Hong Kong, China
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26
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Chan SM, Nelson EA, Leung SS, Li CY. Postnatal iron status of Hong Kong Chinese women in a longitudinal study of maternal nutrition. Eur J Clin Nutr 2001; 55:538-46. [PMID: 11464227 DOI: 10.1038/sj.ejcn.1601180] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2000] [Revised: 01/02/2001] [Accepted: 01/10/2001] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To report postnatal iron nutritional status of Hong Kong Chinese women during the first 6 months postpartum. DESIGN AND SUBJECTS A longitudinal study examining postnatal calcium and iron status of Hong Kong Chinese breastfeeding and formula-feeding women was conducted during 1998. Postpartum women aged 20-40 y, with no bone or blood disorders were recruited and interviewed at 0 (baseline), 2, 6 weeks, 3 and 6 months postpartum. Dietary intake was assessed by a 3 day dietary record and cross checked by a 24 h recall. Complete blood count and serum ferritin level were measured to assess anaemia and iron status. In this report, subjects were divided into an anaemic group (haemoglobin level < 10 g/dl) and a non-anaemic group (haemoglobin level > or = 10 g/dl) according to baseline haemoglobin levels. RESULTS At baseline, 13/47 (27.7%) subjects were anaemic. Two of these 13 anaemic subjects were still anaemic at 3 and 6 months postpartum. Anaemic subjects showed significantly (P < 0.01) greater amounts of blood loss and a higher rate of primary postpartum haemorrhage than the non-anaemic subjects. Daily food intake and dietary nutrient intake did not differ significantly between the two groups. During the first 6 weeks postpartum, subjects in both groups consumed more poultry and egg, and comparable amounts of meat, compared with women in the Hong Kong general population. Iron and vitamin C intakes for the majority of subjects reached 60% of the US Recommended Daily Allowances. Regression analysis suggested that the rate of change in haemoglobin level in the first 6 weeks postpartum was positively correlated with baseline MCV level and serum ferritin level, but negatively correlated with baseline haemoglobin level. CONCLUSIONS Blood loss at delivery is an important factor for postpartum anaemia. Postnatal recovery of iron status of this group of women appeared to be more related to physiological factors than to dietary factors. The role of diet as well as other physiological changes in postpartum women requires further investigation. Finding ways to minimise blood loss at delivery could be the most practical strategy to reduce the rate of postpartum anaemia. SPONSORSHIP CSM was supported by a research studentship from the Research Grants Council, Hong Kong.
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Affiliation(s)
- S M Chan
- Department of Paediatrics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong, People's Republic of China
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27
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Gu PL, Chu KH, Chan SM. Bacterial expression of the shrimp molt-inhibiting hormone (MIH): antibody production, immunocytochemical study and biological assay. Cell Tissue Res 2001; 303:129-36. [PMID: 11236000 DOI: 10.1007/s004410000299] [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: 12/01/2022]
Abstract
Molting in shrimp is controlled by the molt-inhibiting hormone (MIH) and ecdysone. MIH inhibits the synthesis of ecdysone in the Y-organ, resulting in molt suppression; it is a neuropeptide member belonging to the eyestalk CHH/MIH/GIH family. The cloning of MIH (formerly MIH-like) of the shrimp Metapenaeus ensis has been reported in a previous study. To obtain a large quantity of fusion protein for antibody production and biological assay, the cDNA encoding the shrimp MIH was inserted into the pRSET bacterial expression vector. His-tagged fusion protein was produced and purified by an Ni2+-charged affinity column. Polyclonal antibody to rMIH was subsequently obtained by immunizing rabbits with purified recombinant proteins. Results from Western blot analysis indicated that the antibody was specific. Furthermore, results from immunocytochemical analysis showed that specific cells in three different clusters of the X-organ, the sinus gland and the axonal tract of the eyestalk contain MIH. To test for the molt-inhibiting activity of rMIH, shrimp at intermolt stage were injected with rMIH and the molt cycle duration of the injected shrimp was monitored. A significant increase in molt cycle duration was recorded for the shrimp injected with the recombinant protein.
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Affiliation(s)
- P L Gu
- Department of Zoology, The University of Hong Kong, Hong Kong SAR, China
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28
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Abstract
OBJECTIVE A 'ginger vinegar soup' and other special dietary practices have been traditionally recommended for postpartum Chinese women. This paper describes these practices in the first 6 weeks postpartum, and details of the calcium and iron content of the 'ginger vinegar soup'. DESIGN AND SUBJECTS Results of this paper were generated from a longitudinal study on the nutritional status of Hong Kong Chinese postpartum women. 'Ginger vinegar soup' samples were collected at the 2 week home visits. Calcium and iron content were measured by the combination of dry ashing method and atomic absorption spectrophotometry. Results were compared with other types of soup and food sources. A food frequency questionnaire was completed at the 6 week interview to assess the special dietary practices during this period. RESULTS Fifty-one subjects completed the food frequency questionnaires. Twenty-two ginger vinegar soup samples and six other soup samples were collected. Consumption of special food items such as ginger, pig's trotters, egg and chicken varied greatly among subjects. More poultry and similar amounts of egg were consumed by our subjects as compared with the Hong Kong general population. Chicken soup and ginger vinegar soup were commonly consumed. Median calcium and iron contents of the ginger vinegar soup were 4.65 and 0.84 mg/dl, respectively. This calcium content was higher than that of the other six soup samples, but was low as compared with other calcium-rich foods. Iron content of ginger vinegar soup was higher than that of the other six samples and was comparable to some iron-rich foods. CONCLUSIONS Hong Kong Chinese postpartum women followed traditional dietary practices to different degrees. These practices were characterized by an increased poultry consumption. Iron content of ginger vinegar soup was comparable to some iron-rich foods.
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Affiliation(s)
- S M Chan
- Department of Paediatrics, The Chinese University of Hong Kong, Shatin
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29
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Abstract
OBJECTIVE To describe factors associated with breastfeeding failure during the first 6 months post-partum in a sample of Hong Kong Chinese women participating in a longitudinal study of maternal nutrition. METHODOLOGY Forty-four Hong Kong Chinese lactating mothers who intended to breastfeed exclusively for at least 3 months were recruited and followed for 6 months post-partum. Demographic data were compared with 20 mothers who intended to use formula feeding. Mothers were followed up at 2 and 6 weeks and 3 and 6 months and details of infant feeding practices were obtained. Information was sought on breastfeeding management in hospital, reasons for discontinuation of breastfeeding or for providing supplements to babies and intention to seek, and sources of, lactation support. RESULTS Thirty-nine mothers who planned to breastfeed completed the follow up. Compared with mothers in the formula-feeding group, breastfeeding mothers were more likely to be professionals or housewives. Continuation of any breastfeeding (total and partial) was noted in 30 (77%), 22 (57%), 16 (41%) and 12 (31%) mothers at 2 and 6 weeks and 3 and 6 months post-partum, respectively. The majority (97%) of mothers stated that they were given information on the benefits and management of breastfeeding. However, late initiation of breastfeeding and providing supplements to babies were common. Perceptions of insufficient milk supply (44%), breast problems (31%) and being too tired (28%) were the main reasons stated for stopping breastfeeding or for providing supplements to babies. Midwives from the postnatal wards and hotlines were the main sources of lactation support. CONCLUSIONS These results highlight difficulties in sustaining breastfeeding, either exclusive or partial, in Hong Kong Chinese women. Despite being recruited on the basis of intending to exclusively breastfeed for 3 months, less than half these mothers were still breastfeeding and only approximately one-third were exclusively or predominantly breastfeeding at 3 months. More needs to be done within the hospital environment to initiate breastfeeding immediately after birth and to avoid giving unnecessary supplements and more effort is needed to foster a mother's confidence, commitment and knowledge of breastfeeding.
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Affiliation(s)
- S M Chan
- Department of Paediatrics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin
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30
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Abstract
PURPOSE To report the unusual presentation of a confirmed iris lymphoma in the setting of posttransplant lymphoproliferative disorder. DESIGN Case report with clinicopathologic findings. METHODS The medical record was reviewed for clinical manifestations, course of disease, and pathologic and radiologic findings. RESULTS A 4-year-old girl who had undergone a cardiac transplant at 3 months of age was found to have unilateral iris lesions associated with granulomatous uveitis. Her condition was unresponsive to local and systemic steroids, so she underwent an iris biopsy that was found to contain a B cell-derived monoclonal lymphoproliferation. Treatment with systemic chemotherapy including cyclophosphamide and prednisone resulted in a transient, partial response. Localized radiotherapy induced total regression of the iris lesions. She continues to be observed and has been free of recurrence or metastasis for the past 12 months. CONCLUSIONS Because of the increased use of organ transplantation, eye care specialists should consider the diagnosis of intraocular lymphoma when confronted with uveitis-like syndrome unresponsive to topical steroid therapy. Although there are numerous treatment options for intraocular lymphoma, radiation therapy was found to be effective in the treatment of this case.
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Affiliation(s)
- S M Chan
- Department of Ophthalmology, University of Alberta, Edmonton, Alberta, Canada.
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31
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Affiliation(s)
- C Y Chan
- Department of Diagnostic Radiology, Tuen Mun Hospital, Hong Kong, PR of China
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32
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Gu PL, Yu KL, Chan SM. Molecular characterization of an additional shrimp hyperglycemic hormone: cDNA cloning, gene organization, expression and biological assay of recombinant proteins. FEBS Lett 2000; 472:122-8. [PMID: 10781818 DOI: 10.1016/s0014-5793(00)01420-4] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [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: 11/21/2022]
Abstract
The crustacean eyestalk CHH/MIH/GIH neurohormone gene family represents a unique group of neuropeptides identified mainly in crustaceans. In this study, we report the cloning and characterization of the cDNA and the gene encoding the hyperglycemic hormone (MeCHH-B) of the shrimp Metapenaeus ensis. The amino acid sequence of MeCHH-B shows 85% identity to that of MeCHH-A (formerly MeCHH-like neuropeptide). Two separate but identical MeCHH-B genes were identified in the genome of shrimp by library screening and they are located on different CHH gene clusters. The organization of the MeCHH-B gene is identical to other members of the CHH/MIH/GIH neurohormone family. MeCHH-B is expressed at a constant level in the eyestalks of juveniles and mature females. Unlike the MeCHH-A gene, a low level of MeCHH-B transcripts can also be detected in the central nervous system. Interestingly, the expression pattern of MeCHH-B in the eyestalk of vitellogenic females is reversed to that of the MeCHH-A gene. At the middle stage of gonad maturation, a minimum level of MeCHH-B transcript was recorded and a maximum level of MeCHH-A transcript was detected. Recombinant proteins for MeCHH-A and MeCHH-B were produced by a bacterial expression system. The hemolymph glucose level of bilaterally eyestalk-ablated shrimp increased two-fold 1 h after the rCHH injection and then returned to normal after 2 h. The hyperglycemic effect of these fusion proteins is comparable to that of de-stalked shrimp injected with crude extract from a single sinus gland.
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Affiliation(s)
- P L Gu
- Department of Zoology, The University of Hong Kong, Pokfulam Road, Hong Kong, China
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33
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Ganellin CR, Bishop PB, Bambal RB, Chan SM, Law JK, Marabout B, Luthra PM, Moore AN, Peschard O, Bourgeat P, Rose C, Vargas F, Schwartz JC. Inhibitors of tripeptidyl peptidase II. 2. Generation of the first novel lead inhibitor of cholecystokinin-8-inactivating peptidase: a strategy for the design of peptidase inhibitors. J Med Chem 2000; 43:664-74. [PMID: 10691692 DOI: 10.1021/jm990226g] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [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: 01/09/2023]
Abstract
The cholecystokinin-8 (CCK-8)-inactivating peptidase is a serine peptidase which has been shown to be a membrane-bound isoform of tripeptidyl peptidase II (EC 3.4.14.10). It cleaves the neurotransmitter CCK-8 sulfate at the Met-Gly bond to give Asp-Tyr(SO(3)H)-Met-OH + Gly-Trp-Met-Asp-Phe-NH(2). In seeking a reversible inhibitor of this peptidase, the enzymatic binding subsites were characterized using a fluorimetric assay based on the hydrolysis of the artificial substrate Ala-Ala-Phe-amidomethylcoumarin. A series of di- and tripeptides having various alkyl or aryl side chains was studied to determine the accessible volume for binding and to probe the potential for hydrophobic interactions. From this initial study the tripeptides Ile-Pro-Ile-OH (K(i) = 1 microM) and Ala-Pro-Ala-OH (K(i) = 3 microM) and dipeptide amide Val-Nvl-NHBu (K(i) = 3 microM) emerged as leads. Comparison of these structures led to the synthesis of Val-Pro-NHBu (K(i) = 0.57 microM) which served for later optimization in the design of butabindide, a potent reversible competitive and selective inhibitor of the CCK-8-inactivating peptidase. The strategy for this work is explicitly described since it illustrates a possible general approach for peptidase inhibitor design.
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Affiliation(s)
- C R Ganellin
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, England
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Abstract
OBJECTIVE To study the early dietary practices in relation to growth of Hong Kong children from birth to 7 years. METHODOLOGY One hundred and seventy-three full-term Hong Kong Chinese babies were recruited at birth and were followed up for anthropometric measurements using standardized methods and dietary assessment using a combination of dietary history, 24 h recall and food frequency. At 7 years, 125 children remained in the study. RESULTS Mean (SD) birthweight was 3.3 (0.38) kg for boys and 3.1 (0.38) kg for girls. Mean (SD) weight at 7 years was 22.4 (4.2) kg for boys and 21.1 (3.7) kg for girls, and mean (SD) height was 120.3 (4.8) cm for boys and 119.8 (5.1) cm for girls. Hong Kong children were lighter and shorter than Australian children and the National Centre for Health Statistics (NCHS) references, but the magnitude is less than one standard deviation score. Mean weight and height of Hong Kong children were lower compared to Caucasian and Beijing children, with more obvious differences between 1 and 5 years. At 1 year, mean (SD) daily energy intake was 98 (24) kcal/kg/day for boys and 100 (26) kcal/kg/day for girls. By 7 years, it decreased to 82 (18) kcal/kg/day for boys and 73 (22) kcal/kg/day for girls. Between 2 to 4 years of age the energy intake of studied children were slightly lower than the Australian and Finnish children, but the protein intake was higher. Percentage of fat contributing to total daily energy intake was lower throughout at a level of 30%. Such differences in diet reflect a lower consumption of milk fat, higher consumption of meat and lower level of physical activity in Hong Kong children. Intakes of calcium, iron and vitamin C all reached 60% or above of US recommended daily allowance. CONCLUSIONS The smaller body build of Chinese compared to Caucasians cannot be explained by dietary differences. The diet of Hong Kong children is changing to one which is more Westernized with a higher consumption of animal products.
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Affiliation(s)
- S S Leung
- Department of Paediatrics, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin.
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Sung EC, Chan SM, Mito R, Caputo AA. Effect of carbamide peroxide bleaching on the shear bond strength of composite to dental bonding agent enhanced enamel. J Prosthet Dent 1999; 82:595-9. [PMID: 10559733 DOI: 10.1016/s0022-3913(99)70060-0] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.3] [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: 11/18/2022]
Abstract
STATEMENT OF PROBLEM Carbamide peroxide bleaching has been implicated in adversely affecting the bond strength of composite to enamel. PURPOSE This in vitro study evaluated the effect of 3 dental bonding agents (OptiBond, All-Bond 2, One-Step) on the shear bond strength of a hybrid composite to enamel which was treated by a 10% carbamide peroxide bleaching system. MATERIAL AND METHODS Cylinders of composite were bonded to carbamide peroxide-treated enamel on extracted human teeth using 3 dental bonding agents. After thermocycling, shear bond strengths were determined with a universal testing machine. RESULTS OptiBond aided bond strengths were 23.7 +/- 5.6 MPa to bleached and 19.6 +/- 2.9 MPa to unbleached enamel. For All-Bond 2, bleached enamel exhibited bond strengths of 14.9 +/- 4.0 MPa and unbleached enamel exhibited a bond strength value of 20. 4 +/- 2.3 MPa. The composite bond strength for One-Step was 13.6 +/- 5.9 MPa to bleached and 23.0 +/- 3.9 MPa to unbleached enamel. There was no statistical difference between OptiBond (alcohol base) aided bond strengths for bleached and unbleached enamel; however, the bond strength of composite to bleached enamel with All-Bond 2 or One-Step (acetone base) was significantly lower than unbleached controls. CONCLUSION The effect of bonding agent usage on composite bond strength to enamel bleached with a particular carbamide peroxide was dependent on the bonding agent used.
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Affiliation(s)
- E C Sung
- School of Dentistry, University of California at Los Angeles, CA 90095-1668, USA.
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Abstract
To study the role of ecdysone and the ecdysone inducible gene in the regulation of molting and development in crustaceans, we have cloned a cDNA encoding an orphan nuclear receptor family member from the eyestalk of the shrimp Metapenaeus ensis. The size of the cDNA is 4.3 kb with the longest open reading frame (ORF) encoding a protein of 545 amino acid residues. The deduced amino acid sequence of the shrimp cDNA consists of regions that are characteristic of those of the nuclear hormone receptors. It shows a high degree of amino acid sequence identity in the DNA binding domain, ligand binding domain and the FTZ box as compared to those of invertebrates and vertebrates. Unlike the insects Drosophila melanogaster and Bombyx mori, an AF2 transactivation domain was present in the shrimp FTZ-F1. Northern blot analysis using total RNA indicated that the FTZ-F1 mRNA could also be detected in the mature ovary. Northern blot analysis and RT-PCR analysis showed that the shrimp FTZ-F1 transcripts could be detected in the ovary, newly hatched nauplius, testis, eyestalk and epidermis of the adult shrimp. Although the cDNA clone was isolated from the eyestalk library, the shrimp FTZ-F1 appeared to express most abundantly in the mature oocytes. The presence of abundant FTZ-F1 specific maternal message in the late vitellogenic ovary and early nauplius indicates that it may be important for the early embryonic and larval development of the shrimp. Interestingly, shrimp FTZ-F1 can also be found in testis of the male shrimp. The presence of FTZ-F1 in other tissues such as epidermis suggests that it may also be involved in other physiological processes such as molting.
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Affiliation(s)
- S M Chan
- Department of Zoology, The University of Hong Kong, China
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Uger RA, Chan SM, Barber BH. Covalent linkage to beta2-microglobulin enhances the MHC stability and antigenicity of suboptimal CTL epitopes. J Immunol 1999; 162:6024-8. [PMID: 10229842] [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] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Many CTL epitopes of clinical importance, particularly those derived from tumor Ags, display relatively poor MHC binding affinity and stability. Because in vivo immunogenicity, and thus the efficacy of peptide-based vaccines, is thought to be determined by MHC/peptide complex stability, there is a need to develop a simple strategy for enhancing the binding of suboptimal epitopes. Toward this goal, the ability to enhance suboptimal peptides through covalent linkage to beta2-microglobulin (beta2m) was explored. Two suboptimal variants of a high-affinity Db-restricted influenza nucleoprotein peptide were covalently linked, via a polypeptide spacer, to the amino terminus of human beta2m and the recombinant fusion proteins expressed in Escherichia coli. When compared with their uncoupled counterparts, the beta2m-linked epitopes display enhanced MHC stabilization and antigenicity. Thus, tethering epitopes to beta2m provides a simple method for augmenting the biological activity of suboptimal peptides and could be useful in the design of peptide-based vaccines or immunotherapeutics.
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Affiliation(s)
- R A Uger
- Department of Immunology, Medical Sciences Building, University of Toronto, Toronto, Canada
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38
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Abstract
The crustacean hyperglycemic hormone (CHH) plays an important role in the regulation of glucose metabolism. We have cloned and sequenced several cDNAs encoding the preproCHH-like of the shrimp, Metapenaeus ensis. The preproCHH-like peptide of the shrimp consists of a signal peptide, a CHH precursor-like peptide (CPRP) and the CHH-like peptide. Comparative analysis revealed that the signal peptide and the CPRP of the shrimp peptide are the shortest among all the CHHs reported. MeCHH-like is expressed in the eyestalk, but it is not expressed in the heart, hepatopancreas, muscle, nerve cord and pre-hatch embryo. To study the structural organization of the shrimp CHH-like gene, we have screened the genomic DNA library constructed from one shrimp. Three groups of overlapping genomic clones have been isolated. The results from both genomic Southern blot analysis and library screening indicate that the shrimp genome contains at least six copies of the CHH-like genes arranged in a cluster on the chromosome. The size of the CHH-like genes is 1.5-2.1 kb. DNA sequence determinations indicate that the CHH-like genes share 98-100% amino acid sequence identity. There are three exons and two introns in each CHH-like gene. The first intron separates the signal peptide and the second intron separates the mature peptide in the coding region. The 150-200 bp of the upstream 5' flanking region of the CHH-like genes contains promoters with characteristics similar to most eukaryotic genes. Several putative cis-acting elements are also identified in the first 400 bp 5' end upstream region. The organization of the shrimp CHH-like genes is similar to that of the molt inhibiting hormone gene of the same shrimp and the crab, Charybdis feriatus.
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Affiliation(s)
- P L Gu
- Department of Zoology, The University of Hong Kong, China.
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39
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Abstract
A PCR-based genomic DNA walking technique was used to clone the gene for the molt-inhibiting hormone of the crab, Charybdis feriatus. Several overlapping genomic clones were isolated, and the MIH gene for the crab was reconstructed. DNA sequence determination of the overlapping clone reveals that the MIH gene spans 4.3kb and consists of three exons and two introns. Exons 1 and 2 carry a coding sequence for the signal peptide, and exons 2 and 3 consist of coding sequence for the mature peptide. The exon-intron boundary of the crab MIH gene also follows the 'GT-AG rule' for the splice donor and acceptor. The deduced amino acid sequence of MIH shows the highest overall similarity to those of the crabs, Callinectes sapidus and Carcinus maenas, and the gonad-inhibiting hormone (GIH) of the lobster. The putative polyadenylation signal is approximately 1.0kb 3' downstream of the termination codon (TGA). Genomic Southern blot analysis indicates that few genomic fragments were hybridized to the cDNA probe. The 5' flanking region contains a putative promoter with several putative cis elements similar to some vertebrate neuropeptide genes. The 530-bp flanking region was subcloned separately to two promoterless reporter plasmids carrying either the Green Fluorescent Protein gene (GFP) or the Choramphenicol Acetyltransferase gene (CAT). The DNA constructs were transfected into insect cells (Sf21) and mouse pituitary cells (GH4ZR7), respectively. Green fluorescent protein was detected in some of the transfected insect cells, and expression of the CAT was detected in cells transfected with DNA constructs containing the crab promoter. By RT-PCR, MIH transcripts can be detected in the eyestalk of shrimp in intermolt, early premolt, late premolt stages and females that brood their eggs. It can also be found in the brain, but not in the ovary, hepatopancreas, muscle and epidermis. During early larval development, MIH mRNA can be detected in the pre-hatched and the newly hatched larvae. Unlike the adult, the expression of the MIH in the larvae is exclusively in the brain.
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Affiliation(s)
- S M Chan
- Department of Zoology, The University of Hong Kong, Pokfulam Road, Hong Kong, PR
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40
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Abstract
Degenerate primers were derived from the amino acid sequence in the DNA binding domain of the Drosophila ecdysone receptor (DmEcR). Several partial cDNAs were amplified from the shrimp epidermis by reverse transcription polymerase chain reaction (RT-PCR). One of these fragments shows the highest amino acid sequence homology to the insect ecdysone inducible gene E75. This partial cDNA was used as a probe to screen the swimming leg cDNA library of the shrimp, Metapenaeus ensis. A 3.6 kb cDNA clone was obtained. The longest open reading frame of this cDNA consists of 606 amino acids and its deduced amino acid sequence has all five domains typical of a nuclear receptor. The putative polyadenylation signal is located at about 400 bp 3' to the stop signal. The deduced amino acid sequence of this cDNA shows the highest identity to that of the E75A reported in Manduca sexta, Galleria melonella, Drosophila melanogaster, and Choristoneura fumiferana. Based on the amino acid sequence comparison, the shrimp nuclear receptor is considered the insect homologue of E75A. Northern blot analysis shows that the shrimp E75 is expressed in the epidermis, eyestalk and the nerve cord of the pre-molt shrimp. Moreover, E75 transcripts can be detected in the epidermal tissues of early pre-molt shrimp by in situ hybridization. To determine whether the shrimp could also express other E75s like the insects, 5' end RACE and RT-PCR were performed on epidermal cDNA of a single shrimp. Subcloning and DNA sequence determination of the PCR products confirmed the presence of two other forms of E75 (tentatively called E75C and E75D) in shrimp. By RT-PCR, different levels of E75 expression can be detected in the epidermis, nerve cord and the eyestalk of early pre-molt shrimp. In addition to the different levels of expression of the shrimp E75s in the epidermis, the pattern of their expression is also different during the molting cycle. This is the first report on the cloning of a shrimp nuclear receptor superfamily member.
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Affiliation(s)
- S M Chan
- Department of Zoology, The University of Hong Kong, China.
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Gu PL, Chan SM. Cloning of a cDNA encoding a putative molt-inhibiting hormone from the eyestalk of the sand shrimp Metapenaeus ensis. Mol Mar Biol Biotechnol 1998; 7:214-20. [PMID: 9701616] [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] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Degenerate primers were designed from the amino acid sequence of the neuropeptide Pej-SGP-IV of the shrimp Penaeus japonicus. Reverse transcriptase-polymerase chain reaction (RT-PCR) was performed using eyestalk complementary DNA of the sand shrimp Metapenaeus ensis. A partial cDNA that codes for a protein homologous to the neuropeptide Pej-SG-IV was cloned. The partial cDNA was used as a probe to screen the eyestalk cDNA library. Several cDNA clones with nucleotide sequence identical to the partial cDNA were isolated. The largest cDNA is 957 bp with an open reading frame consisting of a coding sequence 315 bp in length. The deduced amino acid of the neuropeptide consists of 77 amino acids and is preceded by a signal peptide of 28 amino acids. Because the deduced amino acid sequence of the shrimp cDNA is highly homologous to the Pej-SGP-IV of P. japonicus (which is molt inhibiting) and to other crustaceans' molt-inhibiting hormones (MIHs), the shrimp neuropeptide is tentatively called MeMIH. Northern blot analysis and RT-PCR showed that MeMIH is expressed in the postmolt, intermolt, and premolt stages of the shrimp eyestalks and the brain. Moreover, RNA message can also be detected in the nervous tissues of newly developed larvae. MeMIH is, however, not found in the muscle, swimming leg, and hepatopancreas. Results from genomic Southern blot analysis and amplification of the shrimp genomic DNA by polymerase chain reaction (PCR) suggest that a single copy of the MIH gene is present in the genome. The structural organization of the gene for the shrimp putative MIH is similar to that of the crab Charybdis feriatus.
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Affiliation(s)
- P L Gu
- Department of Zoology, The University of Hong Kong, Hong Kong
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Chan SM, Hodge WG, Leonard BC. Postoperative Streptococcus pneumoniae endophthalmitis complicated by meningitis. Arch Ophthalmol 1998; 116:951-953. [PMID: 9682715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Affiliation(s)
- S M Chan
- Faculty of Medicine, University of Ottawa, Ontario, Canada
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Chen YR, Lin TH, Chan SM, Chen SW, Yang Y, Ho KC, Young JH. Bilateral choroidal metastases as the initial presentation of a small breast carcinoma: a case report. Zhonghua Yi Xue Za Zhi (Taipei) 1998; 61:99-103. [PMID: 9532872] [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] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Most ocular tumors metastasize from systemic origins in breast carcinoma in females, and bronchial carcinoma in males. Here, we report a case of choroidal carcinoma metastasis from the breast with visual problems being the only initial manifestations. In this case, both eyes were involved at almost the same time, with initial manifestation of blurred vision which progressed to complete visual loss. At first, the patient was diagnosed with malignant melanoma, and enucleation of the right eye was performed in another hospital. However, the tumor had already metastasized rapidly to numerous organs, including the lungs, brain and bone, although it had not affected the liver. Clinical presentations were, therefore, not compatible with those of malignant melanoma, which has usually been reported to metastasize to the liver. Persistent hypercalcemia and raised carcinoembryonic antigen (CEA) concentrations prompted investigations into the possibility of systemic malignancy. A very small breast nodule was finally located by thorough physical examination, and a lumpectomy was performed. A detailed review of the histopathology showed the tumors from the breast and the right eye to have the same origin. Simultaneous bilateral choroidal metastases from other malignancies is not uncommon; however, it is quite rare for breast carcinoma to present with visual problems as a first manifestation. Detailed history taking and physical examination are therefore essential when searching for a primary tumor, so that appropriate therapy can be given earlier.
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Affiliation(s)
- Y R Chen
- Department of Internal Medicine, Taichung Veterans General Hospital, Taiwan, ROC
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Millis JM, Melinek J, Csete M, Imagawa DK, Olthoff KM, Neelankanta G, Braunfeld MY, Sopher MJ, Chan SM, Pregler JL, Yersiz H, Busuttil AA, Shackleton CR, Shaked A, Busuttil RW. Randomized controlled trial to evaluate flush and reperfusion techniques in liver transplantation. Transplantation 1997; 63:397-403. [PMID: 9039930 DOI: 10.1097/00007890-199702150-00012] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [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: 02/03/2023]
Abstract
To determine the impact of different flush and reperfusion techniques on postreperfusion syndrome (PRS) and postoperative graft function, 100 transplants were randomly assigned into four groups as follows: group 1 (n=31), portal vein flush, no vena caval venting; group 2 (n=21), hepatic arterial flush, no vena caval venting; group 3 (n=29), portal vein flush with vena caval venting; and group 4 (n=19), hepatic artery flush with vena caval venting. Donor and recipient characteristics were similar. Extensive intraoperative and postoperative monitoring was performed and measurements were documented immediately before reperfusion and at 1, 5, 15, and 30 min after reperfusion. PRS was defined by three criteria: mean arterial pressure (MAP) <60 mmHg at 1 min after reperfusion, MAP <60 mmHg at 5 min after reperfusion, and a decrease of 30% or more for the MAP percent area under the curve during the initial 5 min after reperfusion (%AUC). Using these definitions, the overall incidence of PRS was 21%, 8%, and 43%, respectively. Group 1 was the most hemodynamically stable; the incidence of PRS in group 1 was 2/31 (7%) at 1 min and 8/31 (25%) using %AUC criteria compared with 7/21 (33%) at 1 min and 12/21 (57%) using %AUC criteria for group 2 (P<0.05). The patients in groups 3 and 4 (vena caval venting) demonstrated smaller percentage increases in serum potassium levels (as determined by %AUC; 4.3+/-6.8 and 0.3+/-5.4, vs. 15.1+/-8.1 for group 1 and 22.9+/-8.2 for group 2). The difference between group 4 and group 2 was statistically significant (P<0.05). The increases in serum potassium did not translate into increased cardiac or hemodynamic instability. Combining all data obtained over the first 30 min after reperfusion, there was no statistically significant difference in hemodynamic or biochemical changes noted among the four groups. Postoperative liver function was similar among the four groups. We conclude that portal vein flush without vena caval venting provided a lower incidence of PRS than any other technique. Vena caval venting decreased the release of potassium into the circulation. Postoperative graft function was not significantly affected by flush and reperfusion techniques.
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Affiliation(s)
- J M Millis
- Department of Anesthesia, UCLA School of Medicine, Los Angeles, California 90024, USA
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Rose C, Vargas F, Facchinetti P, Bourgeat P, Bambal RB, Bishop PB, Chan SM, Moore AN, Ganellin CR, Schwartz JC. Characterization and inhibition of a cholecystokinin-inactivating serine peptidase. Nature 1996; 380:403-9. [PMID: 8602240 DOI: 10.1038/380403a0] [Citation(s) in RCA: 139] [Impact Index Per Article: 5.0] [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: 01/31/2023]
Abstract
A cholecystokinin (CCK)-inactivating peptidase was purified and identified as a membrane-bound isoform of tripeptidyl peptidase II (EC 3.4.14.10), a cytosolic subtilisin-like peptidase of previously unknown functions. The peptidase was found in neurons responding to cholecystokinin, as well as in non-neuronal cells. Butabindide, a potent and specific inhibitor, was designed and shown to protect endogenous cholecystokinin from inactivation and to display pro-satiating effects mediated by the CCKA receptor.
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Affiliation(s)
- C Rose
- Unité de Neurobiologie et Pharmacologie de l'INSERM, Centre Paul Broca, Paris, France
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Affiliation(s)
- L Hao
- Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, Denver 80262
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Hao L, Wang Y, Chan SM, Lafferty KJ. Effect of mycophenolate mofetil on islet allografting to chemically induced or spontaneously diabetic animals. Transplant Proc 1992; 24:2843-4. [PMID: 1465967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- L Hao
- Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, Denver 80262
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Abstract
Embryonic nuclear proteins from the sea urchin Strongylocentrotus purpuratus bind in vitro to a cis-acting element that lies upstream of the actin gene CyIIIb and consists of two direct repeats homologous to steroid hormone response elements. This sea urchin element is specifically recognized by transcription factor COUP-TF from HeLa cell nuclear extracts as well. A sea urchin gene homologous to the human COUP-TF1 gene was detected by blot hybridization to S. purpuratus genomic DNA. Screening of a genomic DNA library with a human COUP-TF1 cDNA probe produced overlapping genomic clones that carry the S. purpuratus gene. Our results indicate that the sea urchin homologue has a structure similar to the human COUP-TF1 gene, i.e., conserved intron positions characteristic of this subgroup of steroid hormone receptors. Sequencing of the exons that encode the DNA- and ligand-binding domains of the sea urchin protein revealed 96% and 92% amino acid identity to the domains of the human protein, respectively. Transcripts derived from the S. purpuratus COUP-TF homologous gene were detected in ovarian and embryonic RNAs from various stages.
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Affiliation(s)
- S M Chan
- Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030
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