1
|
Chen TL, Chen JC, Chang WH, Tsai W, Shih MC, Wildan Nabila A. Imbalanced prediction of emergency department admission using natural language processing and deep neural network. J Biomed Inform 2022; 133:104171. [PMID: 35995106 DOI: 10.1016/j.jbi.2022.104171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 07/14/2022] [Accepted: 08/13/2022] [Indexed: 11/26/2022]
Abstract
The emergency department (ED) plays a very significant role in the hospital. Owing to the rising number of ED visits, medical service points, and ED market, overcrowding of EDs has become serious worldwide. Overcrowding has long been recognized as a vital issue that increases the risk to patients and negative emotions of medical personnel and impacts hospital cost management. For the past years, many researchers have been applying artificial intelligence to reduce crowding situations in the ED. Nevertheless, the datasets in ED hospital admission are naturally inherent with the high-class imbalance in the real world. Previous studies have not considered the imbalance of the datasets, particularly addressing the imbalance. This study purposes to develop a natural language processing model of a deep neural network with an attention mechanism to solve the imbalanced problem in ED admission. The proposed framework is used for predicting hospital admission so that the hospitals can arrange beds early and solve the problem of congestion in the ED. Furthermore, the study compares a variety of methods and obtains the best composition that has the best performance for forecasting hospitalization in ED. The study used the data from a specific hospital in Taiwan as an empirical study. The experimental result demonstrates that almost all imbalanced methods can improve the model's performance. In addition, the natural language processing model of Bi-directional Long Short-Term Memory with attention mechanism has the best results in all-natural language processing methods.
Collapse
Affiliation(s)
- Tzu-Li Chen
- Department of Industrial Engineering and Management, National Taipei University of Technology, Taiwan.
| | - James C Chen
- Department of Industrial Engineering and Engineering Management, National Tsing Hua University, Taiwan
| | - Wen-Han Chang
- Department of Emergency Medicine, Mackay Memorial Hospital, Taiwan
| | - Weide Tsai
- Department of Emergency Medicine, Mackay Memorial Hospital, Taiwan
| | - Mei-Chuan Shih
- Department of Industrial Engineering and Engineering Management, National Tsing Hua University, Taiwan
| | - Achmad Wildan Nabila
- Department of Industrial Engineering and Engineering Management, National Tsing Hua University, Taiwan
| |
Collapse
|
2
|
Wang BY, Ku YL, Sheu SY, Chen LC, Shih MC. [Reducing False Alarms and Absent Treatments by Nurses During Resuscitation in the Emergency Department]. Hu Li Za Zhi 2021; 68:75-84. [PMID: 33792021 DOI: 10.6224/jn.202104_68(2).10] [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] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND & PROBLEMS Medical management protocols prioritize the safety of patients during emergency resuscitation situations. According to a medical center in Taiwan statistics gathered in 2017, the unnecessary activation of resuscitation teams by new nurses because of their improper assessment of patient conditions was a significant cause of anxiety in patient relatives and source of complaints directed at the medical center. In June 2018, 18.7% of the emergency resuscitation calls in the emergency department (ED) were false alarms or absent treatment incidents. After investigation, lack of clearly stated resuscitation team member responsibilities and insufficient practical training for new nurses were primary factors associated with the high rate of false alarm/absent treatment incidents in the ED. PURPOSE To decrease the rate of absent treatment by nurses during resuscitation from 18.7% to 0% in the ED. RESOLUTION The assignments of emergency team members were revised, a new "Emergency app" was introduced, the assignment schedule of the emergency resuscitation team was distributed, SIM realistic education training was held, stronger team work was promoted, and a standard assignment review schedule was established and regularly monitored. RESULTS After the introduction of the resolution measures, the false alarm / absent treatment incidents in the ED caused by ED nurses dropped from 18.7% to 0%. CONCLUSIONS Resuscitation workflow is closely related to patient safety, and teamwork among colleagues critical to successful resuscitation. The project revised resuscitation teamwork assignments and organized resuscitation education training, including simulation courses, to enhance the understanding of team members. The strategy outlined in this paper may be used to raise awareness using posters and resuscitation record checklists to track and manage the team`s progress. This project was designed to enhance teamwork to decrease the rate of absent treatment and to provide safe and quality resuscitation care in order to improve resource management by the team to increase productivity.
Collapse
Affiliation(s)
- Bo-Yu Wang
- BSN, RN, Department of Nursing, Linkou Chang Gung Memorial Hospital, Taiwan, ROC
| | - Ya-Ling Ku
- BSN, RN, Department of Nursing, Linkou Chang Gung Memorial Hospital, Taiwan, ROC
| | - Se-Yin Sheu
- BSN, RN, Department of Nursing, Linkou Chang Gung Memorial Hospital, Taiwan, ROC
| | - Li-Chen Chen
- MS, RN, Deputy Director, Department of Nursing, Linkou Chang Gung Memorial Hospital, Taiwan, ROC
| | - Mei-Chuan Shih
- BSN, RN, Head Nurse, Department of Nursing, Linkou Chang Gung Memorial Hospital, Taiwan, ROC.
| |
Collapse
|
3
|
Chang YC, Chou LT, Lin HL, Huang SF, Shih MC, Wu MC, Wu CL, Chen PT, Chaou CH. An interprofessional training program for intrahospital transport of critically ill patients: model build-up and assessment. J Interprof Care 2019:1-5. [PMID: 30669900 DOI: 10.1080/13561820.2018.1560247] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [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: 01/16/2018] [Revised: 10/30/2018] [Accepted: 12/07/2018] [Indexed: 10/27/2022]
Abstract
Intrahospital transport of critically ill patients for diagnostic or therapeutic procedures can be compromised by patient instability, equipment problems or inexperienced teamworking. This quasi-experimental study aimed to assess the effectiveness of an in-situ interprofessional simulation-based training (IIST) model for junior member transport teams. Newly registered postgraduate physicians, nurses and respiratory therapists underwent the IIST. The technical skills (TS) of each participant and non-technical skills (NTS) of each interprofessional team were assessed using well-validated checklists. Thirty-six participants enrolled and were randomly assigned to six experimental and six control teams. Most participants achieved a significantly higher level of both TS and NTS. Both the control and experimental teams overvalued their NTS in the pretest, while the posttest self-assessment scores among the experimental groups more closely matched the expert assessments. Despite challenges in scheduling and the setting, the IIST was successfully conducted in a crowded hospital, which enabled trainees to optimize their learning in a real-life environment. In conclusion, the IIST model can facilitate the development of both TS and NTS for transport team members. Transport teams made up of newly registered staff from different disciplines may lack insight into their NTS in critical patient transfer management, but simulation training may cause improvements.
Collapse
Affiliation(s)
- Yu-Che Chang
- a Chang Gung Medical Education Research Center, CGMERC , Taiwan
- b Department of Emergency Medicine , Chang Gung Memorial Hospital, Linkou , Taiwan
- c Department of Emergency Medicine , Chang Gung University College of Medicine , Taoyuan City , Taiwan (R.O.C.)
| | - Lan-Ti Chou
- d Department of Respiratory Therapy , Chang Gung Memorial Hospital, Linkou , Taiwan
- e Department of Respiratory Care , Chang Gung University of Science and Technology , Taiwan
| | - Hui-Ling Lin
- f Department of Nursing , Chang Gung Memorial Hospital, Linkou , Taiwan
- g School of Nursing , Chang Gung University of Science and Technology , Taiwan
- h School of Nursing , Chang Gung University , Taiwan
| | - Shu-Fen Huang
- d Department of Respiratory Therapy , Chang Gung Memorial Hospital, Linkou , Taiwan
| | - Mei-Chuan Shih
- f Department of Nursing , Chang Gung Memorial Hospital, Linkou , Taiwan
| | - Mao-Chang Wu
- i Department of Medical Imaging and Intervention , Chang Gung Memorial Hospital, Linkou , Taiwan
| | - Chiao-Lin Wu
- j Department of Otorhinolaryngology, Head and Neck Surgery , Chang Gung Memorial Hospital, Linkou , Taiwan
| | - Pin-Tarng Chen
- k Department of Anesthesiology , Taipei Veterans General Hospital , Taiwan
| | - Chung-Hsien Chaou
- a Chang Gung Medical Education Research Center, CGMERC , Taiwan
- b Department of Emergency Medicine , Chang Gung Memorial Hospital, Linkou , Taiwan
- c Department of Emergency Medicine , Chang Gung University College of Medicine , Taoyuan City , Taiwan (R.O.C.)
| |
Collapse
|
4
|
Mejia J, Reis MA, Miranda ACC, Batista IR, Barboza MRF, Shih MC, Fu G, Chen CT, Meng LJ, Bressan RA, Amaro E. Performance assessment of the single photon emission microscope: high spatial resolution SPECT imaging of small animal organs. Braz J Med Biol Res 2013; 46:936-942. [PMID: 24270908 PMCID: PMC3854337 DOI: 10.1590/1414-431x20132764] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [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: 12/31/2012] [Accepted: 08/21/2013] [Indexed: 01/12/2023] Open
Abstract
The single photon emission microscope (SPEM) is an instrument developed to obtain
high spatial resolution single photon emission computed tomography (SPECT) images of
small structures inside the mouse brain. SPEM consists of two independent imaging
devices, which combine a multipinhole collimator, a high-resolution, thallium-doped
cesium iodide [CsI(Tl)] columnar scintillator, a demagnifying/intensifier tube, and
an electron-multiplying charge-coupling device (CCD). Collimators have 300- and
450-µm diameter pinholes on tungsten slabs, in hexagonal arrays of 19 and 7 holes.
Projection data are acquired in a photon-counting strategy, where CCD frames are
stored at 50 frames per second, with a radius of rotation of 35 mm and magnification
factor of one. The image reconstruction software tool is based on the maximum
likelihood algorithm. Our aim was to evaluate the spatial resolution and sensitivity
attainable with the seven-pinhole imaging device, together with the linearity for
quantification on the tomographic images, and to test the instrument in obtaining
tomographic images of different mouse organs. A spatial resolution better than 500 µm
and a sensitivity of 21.6 counts·s-1·MBq-1 were reached, as
well as a correlation coefficient between activity and intensity better than 0.99,
when imaging 99mTc sources. Images of the thyroid, heart, lungs, and bones
of mice were registered using 99mTc-labeled radiopharmaceuticals in times
appropriate for routine preclinical experimentation of <1 h per projection data
set. Detailed experimental protocols and images of the aforementioned organs are
shown. We plan to extend the instrument's field of view to fix larger animals and to
combine data from both detectors to reduce the acquisition time or applied
activity.
Collapse
Affiliation(s)
- J Mejia
- Hospital Israelita Albert Einstein, Instituto do Cérebro, São Paulo,SP, Brasil
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Martins RCS, Andersen ML, Garbuio SA, Bittencourt LR, Guindalini C, Shih MC, Hoexter MQ, Bressan RA, Castiglioni MLV, Tufik S. Dopamine transporter regulation during four nights of REM sleep deprivation followed by recovery--an in vivo molecular imaging study in humans. Sleep 2010; 33:243-51. [PMID: 20175408 PMCID: PMC2817911 DOI: 10.1093/sleep/33.2.243] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [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: 11/14/2022] Open
Abstract
OBJECTIVES To assess the influence of total or selective REM sleep deprivation on the dopamine transporter (DAT) densities and sleep patterns of healthy volunteers. DESIGN Prospective study. SETTING Evaluation of polysomnography recordings and DAT density after 4 nights of selective REM sleep deprivation followed by 3 nights of sleep recovery compared to a control group and a group that was subjected to 2 nights of total sleep deprivation. Single positron emission computed tomography and [99mTc]TRODAT-1 were used to assess the cerebral DAT density in the striatum at baseline, after REM sleep deprivation and total sleep deprivation as well as after sleep recovery. Blood was collected daily to examine prolactin and estradiol levels, which were correlated with dopaminergic activity. PATIENTS OR PARTICIPANTS Thirty healthy male volunteers ranging from 19 to 29 years of age were randomly assigned to one of three experimental groups after giving written informed consent (10 non-sleep deprived, 10 total sleep deprived, and 10 REM sleep deprived). MEASUREMENTS AND RESULTS Four nights of REM sleep deprivation and 2 nights of total sleep deprivation induced distinct and heterogeneous patterns of sleep recovery. No significant modulation of DAT availability was observed within groups. In the recovery nights, changes in cortisol, prolactin and estradiol concentrations were significantly correlated with specific sleep stages in the total and REM sleep deprived groups. In addition, DAT density was positively correlated with estradiol concentration and inversely associated with SWS latency only after total sleep deprivation. CONCLUSION Our study demonstrates that although sleep deprivation did not promote significant alterations in DAT density within the striatum, there were significant correlations among transporter availability, hormonal concentrations and sleep parameters.
Collapse
Affiliation(s)
- R C S Martins
- Department of Psychobiology-Universidade Federal de São Paulo, Escola Paulista de Medicina (UNIFESP/EPM), Brazil
| | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Martins RCS, Andersen ML, Shih MC, Tufik S. Effects of cocaine, methamphetamine and modafinil challenge on sleep rebound after paradoxical sleep deprivation in rats. Braz J Med Biol Res 2008; 41:68-77. [PMID: 18157430 DOI: 10.1590/s0100-879x2008000100011] [Citation(s) in RCA: 13] [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] [Subscribe] [Scholar Register] [Received: 05/21/2007] [Accepted: 10/26/2007] [Indexed: 11/22/2022] Open
Abstract
Sleep loss is both common and critically relevant to our society and might lead to the abuse of psychostimulants such as amphetamines, cocaine and modafinil. Since psychoactive substance abuse often occurs within a scenario of sleep deficit, the purpose of this investigation was to compare the sleep patterns of rats challenged with cocaine (7 mg/kg, ip), methamphetamine (7 mg/kg, ip), or modafinil (100 mg/kg, ip) subsequent to paradoxical sleep deprivation (PSD) for 96 h. Our results show that, immediately after 96 h of PSD, rats (10 per group) that were injected with a psychostimulant presented lower percentages of paradoxical sleep compared to those injected with saline (P < 0.01). Regarding slow wave sleep (SWS), rats injected with psychostimulants after PSD presented a late rebound (on the second night subsequent to the injection) in the percentage of this phase of sleep when compared to PSD rats injected with saline (P < 0.05). In addition, the current study has produced evidence of the characteristic effect of each drug on sleep architecture. Home cage control rats injected with modafinil and methamphetamine showed a reduction in SWS compared with the saline group. Methamphetamine affected sleep patterns most, since it significantly reduced paradoxical sleep, SWS and sleep efficiency before and after PSD compared to control (P < 0.05). Cocaine was the psychostimulant causing the least changes in sleep pattern in relation to those observed after saline injection. Therefore, our results suggest that abuse of these psychostimulants in a PSD paradigm aggravates their impact on sleep patterns.
Collapse
Affiliation(s)
- R C S Martins
- Departamento de Psicobiologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | | | | | | |
Collapse
|
7
|
Hoexter MQ, Shih MC, Mendes DD, Godeiro-Junior C, Felicio AC, Fu YK, Tufik S, Bressan RA. Lower dopamine transporter density in an asymptomatic patient with Kleine-Levin syndrome. Acta Neurol Scand 2008; 117:370-3. [PMID: 18028505 DOI: 10.1111/j.1600-0404.2007.00942.x] [Citation(s) in RCA: 11] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Kleine-Levin syndrome (KLS) is a rare disorder whose pathophysiological mechanisms remain unknown. PATIENTS AND METHODS To investigate dopamine abnormalities in KLS, a [99mTc]-TRODAT-1 single photon emission computerized tomography (SPECT) was performed in a patient with KLS during the asymptomatic period and compared with three matched healthy controls. RESULTS The patient had 14% lower striatal dopamine transporter binding potential (DAT-BP) compared to the mean DAT-BP of three healthy controls. CONCLUSION This study provides in vivo evidence for abnormalities in the DAT-BP, suggesting an involvement of the dopaminergic system in the pathophysiology of KLS.
Collapse
Affiliation(s)
- M Q Hoexter
- LiNC-Laboratório Interdisciplinar de Neurociências Clínicas, Universidade Federal de São Paulo, São Paulo, Brazil.
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Shih MC, Felicio AC, de Oliveira Godeiro-Junior C, de Carvalho Aguiar P, de Andrade LAF, Ferraz HB, Bressan RA. Molecular imaging in hereditary forms of parkinsonism. Eur J Neurol 2007; 14:359-68. [PMID: 17388981 DOI: 10.1111/j.1468-1331.2007.01691.x] [Citation(s) in RCA: 6] [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: 11/28/2022]
Abstract
The development of in vivo molecular imaging to evaluate the dopamine (DA) system with positron-emission tomography and single photon emission computed tomography has been of key importance on monitoring in vivo nigrostriatal neuronal loss in Parkinson's disease (PD), mostly through assessments of pre- and post-synaptic DA receptors. The discoveries of genes related to hereditary forms of parkinsonism (PARK1, PARK2, PARK6, PARK7 and PARK8) have increased our understanding either of distinct subtypes of clinical expression in PD or its etiology. This article revises current data on molecular neuroimaging of genetic forms of parkinsonism comparing and contrasting its main features with the classical sporadic forms. Awareness of the spectrum variance in the genotype and its respective PD phenotype are useful to distinguish different pathophysiological mechanisms of PD.
Collapse
Affiliation(s)
- M C Shih
- Laboratório Interdiciplinar de Neuroimagem e Cognição (LiNC), Universidade Federal de São Paulo, São Paulo, Brazil.
| | | | | | | | | | | | | |
Collapse
|
9
|
Parsons SK, Shih MC, Mayer DK, Barlow SE, Supran SE, Levy SL, Greenfield S, Kaplan SH. Preliminary psychometric evaluation of the Child Health Ratings Inventory (CHRIs) and Disease-Specific Impairment Inventory-Hematopoietic Stem Cell Transplantation (DSII-HSCT) in parents and children. Qual Life Res 2005; 14:1613-25. [PMID: 16110940 DOI: 10.1007/s11136-005-1004-2] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [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: 11/25/2022]
Abstract
PURPOSE To describe the initial results of the Child Health Ratings Inventory (CHRIs), 20-item generic health-related quality of life (HRQL) instrument and the 10-item disease-specific (DS) module, the Disease Specific Impairment Inventory-Hematopoietic Stem Cell Transplantation (DSII-HSCT), for children and adolescents, ages 5-18 years and their parents following HSCT. STUDY DESIGN Using cross sectional design, 122 children with a median age of 11 years (range 5.0-18 years) completed the questionnaire (CHRIs + DSII-HSCT) with research assistance. Seventy-four parents independently completed a parallel version of the questionnaire; health care providers assigned a global clinical severity rating. RESULTS The generic core includes four domains: physical, role, and emotional functioning, and energy. The DS module has three domains: worry, hassles, and body image. The Cronbach's alpha for parents and for older children (8 years and over) exceeded 0.70 for all generic and DS domains. While the range of alpha coefficients was lower for younger children, ages 5-7 year, only the alpha coefficient for one domain (energy) was less than 0.70. The instrument satisfactorily discriminated between clinically important groups: those early in the transplant process (< 6 months) versus those later (> 12 months) and by provider-assigned clinical severity ratings. CONCLUSION results suggest that the CHRIs generic core and its DSII-HSCT module is a promising measure of HRQL after pediatric HSCT. Although parent and child reports were moderately correlated and revealed complementary results, the unique perspectives of both raters provide a more complete picture of HRQL. Longitudinal application is underway to further characterize the measurement properties of the CHRIs and to determine the instrument's responsiveness and sensitivity to change over time in this vulnerable population.
Collapse
Affiliation(s)
- S K Parsons
- Center on Child and Family Outcomes, Institute for Clinical Research and Health Policy Studies, Tufts-New England Medical Center, Boston, MA 02111, USA.
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Abstract
From 1991 to 2000, amongst 23,886 full-term healthy Chinese babies delivered at our hospital, 2615 babies developed neonatal hyperbilirubinaemia. After excluding other causes of hyperbilirubinaemia and identifying the irregular antibodies, 15 cases of haemolytic disease of the newborn (HDN) due to maternal irregular antibodies were diagnosed; three cases were born in our hospital and 12 cases were referred. Amongst these 15 babies, six cases had HDN due to anti-E, three cases due to anti-E + c, three cases due to anti-D, one case due to anti-c and two cases due to 'Mi' antibodies reacting with MiIII phenotype cells (anti-Hil and anti-Mur). Although there were four cases of hydrops fetalis, only one of the patients expired. The prevalence of HDN caused by maternal irregular antibodies has been estimated to be 0.01%. Therefore, routine prenatal screening for irregular antibodies was not rational in the Chinese population in Taiwan. Anti-E and anti-E + c were the important irregular antibodies resulting in HDN. Although few cases of HDN due to anti-'Mi' have been reported, Anti-'Mi' is significant in regions with a high prevalence of the MiIII phenotype.
Collapse
Affiliation(s)
- K H Wu
- China Medical College Hospital, Taichung, Taiwan
| | | | | | | | | |
Collapse
|
11
|
Shih MC, Liu TC, Lin IL, Lin SF, Chen CM, Chang JG. Gene frequencies of the HPA-1 to HPA-13, Oe and Gov platelet antigen alleles in Taiwanese, Indonesian, Filipino and Thai populations. Int J Mol Med 2003; 12:609-14. [PMID: 12964043 DOI: 10.3892/ijmm.12.4.609] [Citation(s) in RCA: 2] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Human platelet antigen (HPA) systems consist of more than twelve bi-allelic antigen polymorphisms in which a base pair substitution leads to change in an amino acid of a glycoprotein expressed on the platelet. The neonatal alloimmune thrombocytopenia (NAIT), post transfusion purpura, and refractoriness to platelet transfusion can be induced by antibodies against human platelet antigens: e.g. HPA-1a, 3a, 4a, 5a, and Gova. HPA typing is essential for the diagnosis and treatment of a variety of diseases. We developed a PCR-based method to detect HPA-1 to HPA-13, Oe and Gov platelet alloantigens. In this method, the amplified PCR products were used to recognize the polymorphism after restriction enzyme digestions. Among 566 Taiwanese, 107 Indonesian, 100 Filipino and 137 Thai subjects studied, HPA-1a, 2a, 4a, 5a, 6a, 7aW, 8aW, 9a, 10a, 11a, 12a, 13a, Oea genes were present in every sample; while HPA-1b, 2b, 4b, 5b and 6b were rarely found. HPA-7aW, 8aW, 9, 10, 11, 12, 13, and Oea alleles were noted to be monomorphic only. HPA-3a/3b alleles had frequencies of 0.595/0.405, 0.505/0.495, 0.507/0.493, 0.530/0.470, while Gova/Govb of 0.462/0.538, 0.450/0.550, 0.463/0.537, 0.520/0.480 among Taiwanese, Indonesians, Thais and Filipinos respectively. The prevalence rates of HPA-1 to 13 in this study were also consistent with other previous reports using different methods. The alloimmunization due to Gov and HPA-3 antigens need to be emphasized in these populations.
Collapse
Affiliation(s)
- M C Shih
- Departments of Medical Technology and Laboratory Medicine, China Medical University and Hospital, 2 Yuh Der Road, Taichung, Taiwan.
| | | | | | | | | | | |
Collapse
|
12
|
Abstract
Anti-'Mia' is the most common alloantibody of potential clinical significance in the Taiwanese population. The Mi.III phenotype is rare among Caucasians but has a high incidence in various Oriental populations. We describe a nulliparous woman with no history of transfusions, who had hydrops foetalis at 28 weeks gestation. Foetal haemoglobin was 4.4 g dL-1, and a positive direct antiglobulin test was positive in the foetal blood. Intrauterine intravascular transfusion was given, and the baby was discharged healthy. Anti-'Mia' was identified in the maternal serum, the cord blood serum and the eluate from red cells of the cord blood. Anti-'Mia' in the maternal serum was confirmed to be anti-Mur. The polymerase chain reaction-restriction fragment length polymorphism method confirmed that both the baby and her father had the Mi.III gene. Therefore, our report documents that anti-Mur has the potential to cause hydrops foetalis.
Collapse
Affiliation(s)
- K H Wu
- China Medical College Hospital, Taichung, Taiwan
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Liu TC, Shih MC, Lin CL, Lin SF, Chen CM, Chang JG. Gene frequencies of the HPA-1 to HPA-8w platelet antigen alleles in Taiwanese, Indonesian, and Thai. Ann Hematol 2002; 81:244-8. [PMID: 12029532 DOI: 10.1007/s00277-002-0451-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2001] [Accepted: 03/04/2002] [Indexed: 11/28/2022]
Abstract
Human platelet antigen (HPA) systems consist of more than eight biallelic antigen polymorphisms in which a base pair substitution leads to change in an amino acid of a glycoprotein expressed on the platelet. HPA typing is essential in the diagnosis and treatment for a variety of diseases. We developed a polymerase chain reaction (PCR)-based method to detect HPA-1 through HPA-8w. In this method, the amplified PCR products were used to recognize the polymorphism after restriction enzyme digestions. Among 295 Taiwanese, 107 Indonesian, and 137 Thai subjects studied, HPA-1a, 2a, 4a, 5a, 6a, 7aw, and 8aw genes were present in every sample tested. HPA-1b, 2b, 4b, 5b, and 6b were rarely found among subjects. Only monomorphic HPA-7aw and 8aw alleles were noted in the samples. HPA-3a and 3b alleles showed frequencies of 0.595/0.405, 0.504/0.496, and 0.507/0.493 in Taiwanese, Indonesian, and Thai subjects, respectively. Our report is the first PCR-based method to detect most of the HPA antigen variants in Taiwanese, Indonesian, and Thai. The genomic typing results were also confirmed by direct sequencing for uncertain and some representative cases. The prevalence rates of HPA-1, 2, 3, 4, and 5 in this study were also consistent with other previous reports using different methods.
Collapse
Affiliation(s)
- T C Liu
- Division of Hemato-Oncology, Department of Medicine, Kaohsiung Medical University Hospital, Taiwan
| | | | | | | | | | | |
Collapse
|
14
|
Affiliation(s)
- J G Chang
- Department of Laboratory Medicine, China Medical College Hospital, Taichung, Taiwan.
| | | | | | | | | |
Collapse
|
15
|
Abstract
Mutations of the telomeric survival motor neuron gene (SMN1) are related to spinal muscular atrophy (SMA). However, no phenotype-genotype correlation has been observed since the SMN1 gene is lacking in the majority of patients affected with either the severe form (type I) or the milder forms (types II and III). Here, we analyze the SMN, NAIP and P44 genes in 132 Chinese SMA patients and their families. At least three types of normal allele, and four types of mutant allele were found in this study. The combination of one normal allele with one mutant allele resulted in carriers of different types, and the combination of different mutant alleles accounted for the different genotypes among different types of SMA. Deletions of mutant alleles can be further subgrouped into four types, which includes involving SMN1, SMN1 and NAIP(T) (telomeric portion of NAIP gene), SMN1 and NAIP(T) and P44(T) (telomeric portion of P44 gene), and SMN1 and SMN2 (centromeric portion of SMN gene). Some of the severe (type I) SMA cases correlated with the extent of deletions in the SMN, NAIP and P44 genes or the dosage of SMN gene when both SMN1 and SMN2 are deleted. We also found two novel point mutations, an A insertion at codon 8 (AGT-->AAGT) and an A substitution at codon 228 (TTA-->TAA).
Collapse
Affiliation(s)
- C H Tsai
- Department of Medical Research, China Medical College Hospital, 2 Yuh Der Road, Taichung, Taiwan
| | | | | | | | | | | | | |
Collapse
|
16
|
Peng HP, Chan CS, Shih MC, Yang SF. Signaling events in the hypoxic induction of alcohol dehydrogenase gene in Arabidopsis. Plant Physiol 2001; 126:742-9. [PMID: 11402202 PMCID: PMC111164 DOI: 10.1104/pp.126.2.742] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2000] [Revised: 12/15/2000] [Accepted: 01/09/2001] [Indexed: 05/19/2023]
Abstract
Expression of the alcohol dehydrogenase gene (ADH) of Arabidopsis is induced during hypoxia. Because many plants increase their ethylene production in response to hypoxic stress, we examined in this report whether ethylene is involved in the hypoxic induction of ADH in Arabidopsis. We found that the hypoxic induction of ADH can be partially inhibited by aminooxy acetic acid, an inhibitor of ethylene biosynthesis. This partial inhibition can be reversed by the addition of 1-aminocyclopropane-1-carboxylic acid, a direct precursor of ethylene. In addition, the hypoxic induction of the ADH gene is also reduced in etr1-1 and ein2-1, two ethylene insensitive mutants in ethylene-signaling pathways, whereas the addition of exogenous ethylene or an increase in cellular ethylene alone does not induce ADH under normoxic conditions. Kinetic analyses of ADH mRNA accumulation indicated that an ethylene signal is required for the induction of ADH during later stages of hypoxia. Therefore, we conclude that ethylene is needed, but not sufficient for, the induction of ADH in Arabidopsis during hypoxia.
Collapse
Affiliation(s)
- H P Peng
- Department of Biological Sciences, 204 Chemistry Building, University of Iowa, Iowa City, Iowa 52242, USA
| | | | | | | |
Collapse
|
17
|
Chan CS, Guo L, Shih MC. Promoter analysis of the nuclear gene encoding the chloroplast glyceraldehyde-3-phosphate dehydrogenase B subunit of Arabidopsis thaliana. Plant Mol Biol 2001; 46:131-41. [PMID: 11442054 DOI: 10.1023/a:1010602031070] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The promoter of the nuclear gene, GAPB, which encodes the B subunit of chloroplast glyceraldehyde-3-phosphate dehydrogenase (GADPH) of Arabidopsis thaliana, was previously shown to contain four direct repeats (Gap boxes, located between -237 and -181) that were necessary but not sufficient for light-activated gene transcription. To identify additional elements located between the Gap boxes and TATA box, various GAPB promoter fragments driving the beta-glucuronidase (GUS) reporter gene were constructed in transgenic Arabidopsis. We found a 23 bp element (the XXIII element), centered at -119, that is essential for promoter activity. Mutations in the XXIII element abolished transcription of GAPB completely. Furthermore, we have identified three additional elements, PI, Tboxes, and PII that serve as positive modulators in the light-activated transcription of GAPB. Mutations in any of these three elements resulted in the reduction in light inducibility of the GAPB gene. The PI, XXIII, Tboxes and PII sequences are novel cis-acting elements that are not present in the closely related GAPA promoter or other promoters that are similarly regulated by light. In our current study, we found that transgenic Arabidopsis containing a GAPB promoter::GUS construct with all four Gap boxes deleted exhibited significant GUS expression albeit reduced to 42% of the optimal expression level. In contrast, in previous studies on transgenic tobacco, total abolishment of GUS expression was seen when the Gap boxes were deleted. This suggests that different trans-acting factors present in heterologous systems may result in variability of the expression of the transgene.
Collapse
Affiliation(s)
- C S Chan
- Department of Biological Sciences, University of Iowa, Iowa City 52242, USA
| | | | | |
Collapse
|
18
|
Abstract
G1P[6] rotaviruses were demonstrated previously to be associated with the neonatal nursery outbreak of gastroenteritis in Changhua Christian Hospital that is located in the central region of Taiwan, from September 1994 to May 1995. Meanwhile, rotaviruses were detected in children hospitalized for acute gastroenteritis. Our study characterizes the rotaviruses associated with the nursery outbreak by using genetic approaches. Nucleotide sequence analysis revealed that the VP7 genes of the nursery rotaviruses were distinct from those of the strains circulating in the community. The G1P[6] rotaviruses recovered from the nursery were closely related to another neonatal G1P[6] strain from the northern region of Taiwan in both the VP4 and VP7 genes. The VP4 genes of these nursery strains differed from those of the P[6] human reference strains 1076, M37, RV3, and ST3. Apparently, these nursery rotaviruses were distinct from the strains circulating in the community and seemed to be a variant when compared with P[6] strains reported previously.
Collapse
Affiliation(s)
- C N Lee
- School and Graduate Institute of Medical Technology, College of Medicine, National Taiwan University, Taipei, Taiwan, Republic of China.
| | | | | | | | | | | |
Collapse
|
19
|
Kuo CC, Shih MC, Kuo YH, Chiang W. Antagonism of free-radical-induced damage of adlay seed and its antiproliferative effect in human histolytic lymphoma U937 monocytic cells. J Agric Food Chem 2001; 49:1564-1570. [PMID: 11312897 DOI: 10.1021/jf001215v] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [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
The goal of our current research was to investigate the antioxidative effects of methanolic extracts from different parts of adlay seed and their antiproliferative activity in malignant human cells. The methanolic extracts from different parts of adlay seeds were from the hull (AHM), testa (ATM), bran (ABM), and polished adlay (PAM). AHM exhibited greater capacity to scavenge superoxide anion radicals in the PMS-NADH system than ATM, ABM, or PAM. The scavenging capacities of AHM and ATM on hydrogen peroxides were about 20% at a dose of 250 microg/mL. Using the method of deoxyribose degradation to assess damage caused by hydroxyl radicals, AHM was found to inhibit damage in deoxyribose at a higher concentration. However, ATM, ABM, and PAM exhibited prooxidative activity at the same concentration. The inhibitory effect on enzymatic oxidation of xanthine to uric acid was found to follow the order AHM > ATM =. ABM. However, PAM was inactive. All test samples were positive for inhibition of TPA-induced free radical formation on neutrophil-like leukocytes and were found to follow the order AHM > ATM > ABM > PAM. When human histolytic lymphoma U937 monocytic cells were exposed to tert-butyl hydroperoxide, AHM protected the cells against the cytotoxicity caused by tert-butyl hydroperoxide. In addition, AHM exhibited antiproliferative activity against human histolytic lymphoma U937 monocytic cells in a dose-dependent manner. The antiproliferative properties of AHM appear to be attributable to its induction of apoptotic cell death as determined by flow cytometry. These results show that AHM displays multiple antioxidant effects and induces apoptosis of malignant human cells.
Collapse
Affiliation(s)
- C C Kuo
- Graduate Institute of Food Science and Technology, National Taiwan University, Taipei, Taiwan, Republic of China
| | | | | | | |
Collapse
|
20
|
Abstract
Non-parametric linkage analysis examines similarities among affected relatives in alleles of one or more genetic markers (pieces of DNA at known locations on a chromosome). The objective is to evaluate departures from the null hypothesis that the markers are not near a disease gene. Under the null hypothesis, Mendel's laws give the probabilities that a set of relatives exhibits a particular allele-sharing pattern, and the null hypothesis is rejected if the extent of allele sharing among affected relatives exceeds Mendelian expectation. Because the rationale for allele-sharing methods is intuitively plausible and easily grasped, geneticists have used these methods for more than 30 years, well before the advent of the large sets of polymorphic markers that have made linkage analysis so fruitful today. Here we describe methods for assessing whether the extent of marker allele sharing among affected relatives exceeds Mendelian expectation. We first quantify the notion of allele sharing and the probabilities of allele sharing in various sets of relatives. Then we describe allele sharing methods for affected sibs and more general sets of relatives. We also discuss related issues of test size and power. We conclude with a brief discussion of areas in need of further research.
Collapse
Affiliation(s)
- M C Shih
- Department of Health Research and Policy, Stanford University School of Medicine, Stanford, California 94305, USA
| | | |
Collapse
|
21
|
|
22
|
Yeh KT, Chang JG, Chen YJ, Chen ST, Yu SY, Shih MC, Perng LI, Wang JC, Tsai M, Chang CP. Mutation analysis of the putative tumor suppressor gene PTEN/MMAC1 in hepatocellular carcinoma. Cancer Invest 2000; 18:123-9. [PMID: 10705874 DOI: 10.3109/07357900009038243] [Citation(s) in RCA: 24] [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: 12/18/2022]
Abstract
Loss of heterozygosity of chromosome 10q has been reported in hepatoma. Areas with a high rate of loss of genetic material could harbor putative tumor suppressor genes. PTEN/MMAC1, a candidate tumor suppressor gene located at chromosome 10q23.3, has recently been identified and found to be homozygously deleted or mutated in several different types of human tumors. To determine whether the PTEN/MMAC1 gene is a target of 10q loss of heterozygosity in hepatoma, we examined 42 primary hepatomas for mutations in PTEN/MMAC1 by using nested reverse transcriptase polymerase chain reaction (RT-PCR) of the RNA and single-stranded conformation polymorphism (SSCP) analysis of all genomic exons. Although 2 of 42 hepatoma tissues had aberrant transcripts, 5 matched noncancerous liver tissues also had aberrant transcripts. Southern blot analysis of the entire genomic DNA revealed no genomic change. Therefore, like the TSG101 or FHIT gene, aberrant transcripts of PTEN/MMAC1 using the nested RT-PCR method were a common phenomenon for both cancerous and noncancerous liver tissues, which may not be related to oncogenesis. None of the 42 cases had small deletions, point mutations, or insertions. Our results suggest that the PTEN/MMAC1 gene may not play a role in the pathogenesis of hepatoma.
Collapse
Affiliation(s)
- K T Yeh
- Department of Medical Research, China Medical College Hospital, Taichung, Taiwan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Abstract
BACKGROUND Antigens in the human red cell Miltenberger series are glycophorin variants of the MN (MNS) blood group system that are due to the rearrangement of glycophorin A (GPA) and glycophorin B (GPB) genes. STUDY DESIGN AND METHODS Taking advantage of the differences between the GPA and GPB genes, a polymerase chain reaction-based method was developed to detect all the Miltenberger glycophorin variants and St(a) subtype. GPA- and GPB-specific primers were used to amplify the GPA or GPB gene, and the amplified products were used to recognize the different hybrid genes after restriction enzyme digestions. RESULTS Among 264 Taiwanese subjects studied, Mi.III and St(a) are the most common types of Miltenberger variants found. Mi.III was present in 13 (4.92%) of 264, and St(a) was found in 8 (3. 03%) of 264; 1 case (0.4%) of Mi.V was also identified from the study group. CONCLUSION This is the first polymerase chain reaction-based method of detecting most of the Miltenberger variants and St(a). The genomic typing results were confirmed by control DNA of identified Miltenberger phenotypes. The prevalence rates of Mi. III and St(a) in this study were also consistent with other previous reports using different methods.
Collapse
Affiliation(s)
- M C Shih
- Department of Laboratory Medicine, School of Pharmacy, Taichung, Taiwan
| | | | | | | |
Collapse
|
24
|
Chen ST, Yu SY, Tsai M, Yeh KT, Wang JC, Kao MC, Shih MC, Chang JG. Mutation analysis of the putative tumor suppression gene PTEN/MMAC1 in sporadic breast cancer. Breast Cancer Res Treat 1999; 55:85-9. [PMID: 10472782 DOI: 10.1023/a:1006142919428] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [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: 12/14/2022]
Abstract
PTEN/MMAC1, a potential human tumor suppressor gene, has been found to have inactivating mutations in several types of cancer, including breast cancer. The incidence of breast cancer in Chinese is quite low in comparison with Caucasians, and genetic factors may play some roles. To further determine the role of PTEN/MMAC1 in breast cancer in Chinese, we used loss of heterozygosity (LOH), single strand conformation polymorphism (SSCP) with direct sequencing of variant bands, and Southern blot analysis methods to analyze mutations in PTEN/MMAC1 in 52 cases of breast cancer. None had LOH at chromosome 10q23.3. One mutation was identified, a somatic 3-base deletion, in one case. Our results suggest PTEN/MMAC1 does not play a major role in the development of sporadic breast cancer.
Collapse
Affiliation(s)
- S T Chen
- Department of Medical Research, China Medical College Hospital, Taichung, Taiwan
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Conley TR, Peng HP, Shih MC. Mutations affecting induction of glycolytic and fermentative genes during germination and environmental stresses in Arabidopsis. Plant Physiol 1999; 119:599-608. [PMID: 9952456 PMCID: PMC32137 DOI: 10.1104/pp.119.2.599] [Citation(s) in RCA: 17] [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] [Received: 09/08/1998] [Accepted: 10/28/1998] [Indexed: 05/18/2023]
Abstract
Expression of the alcohol dehydrogenase gene (ADH) of Arabidopsis is known to be induced by environmental stresses and regulated developmentally. We used a negative-selection approach to isolate mutants that were defective in regulating the expression of the ADH gene during seed germination; we then characterized three recessive mutants, aar1-1, aar1-2, and aar2-1, which belong to two complementation groups. In addition to their defects during seed germination, mutations in the AAR1 and AAR2 genes also affected anoxic and hypoxic induction of ADH and other glycolytic genes in mature plants. The aar1 and aar2 mutants were also defective in responding to cold and osmotic stress. The two allelic mutants aar1-1and aar1-2 exhibited different phenotypes under cold and osmotic stresses. Based on our results we propose that these mutants are defective in a late step of the signaling pathways that lead to increased expression of the ADH gene and glycolytic genes.
Collapse
Affiliation(s)
- T R Conley
- Department of Biological Sciences, 204 Chemistry Building, University of Iowa, Iowa City, Iowa 52242, USA
| | | | | |
Collapse
|
26
|
Chang JG, Wang JC, Yang TY, Tsan KW, Shih MC, Peng CT, Tsai CH. Human RhDel is caused by a deletion of 1,013 bp between introns 8 and 9 including exon 9 of RHD gene. Blood 1998; 92:2602-4. [PMID: 9746809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
|
27
|
Park SC, Kwon HB, Shih MC. Cis-acting elements essential for light regulation of the nuclear gene encoding the A subunit of chloroplast glyceraldehyde 3-phosphate dehydrogenase in Arabidopsis thaliana. Plant Physiol 1996; 112:1563-71. [PMID: 8972600 PMCID: PMC158089 DOI: 10.1104/pp.112.4.1563] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We report the characterization of cis-acting elements involved in light regulation of the nuclear gene (GapA) that encodes the A subunit of glyceraldehyde 3-phosphate dehydrogenase in Arabidopsis thaliana. Our previous deletion analyses indicate that the -277 to -195 upstream region of GapA is essential for light induction of the beta-glucuronidase reporter gene in transgenic tobacco (Nicotiana tabacum) plants. This region contains three direct repeats with the consensus sequence 5'-CAAATGAA(A/G)A-3' (Gap boxes). Our results show that 2-bp substitutions of the last four nucleotides (AA or GA) of the Gap boxes by CC abolish light induction of the beta-glucuronidase reporter gene in vivo and affect binding of the Gap box binding factor in vitro. We have also identified an additional cis-acting element, AE (Activation Element) box, that is involved in regulation of GapA. A combination of a Gap box trimer and an AE box dimer can confer light responsiveness of the cauliflower mosaic virus 35S promoter containing the -92 to +6 upstream sequence, whereas oligomers of Gap boxes or AE boxes alone cannot confer light responsiveness on the same promoter. These results suggest that Gap boxes and AE boxes function together as the light-responsive element of GapA.
Collapse
Affiliation(s)
- S C Park
- Department of Biological Sciences, University of Iowa, Iowa City 52242, USA
| | | | | |
Collapse
|
28
|
Pan HB, Huang JS, Chen CT, Shih MC, Mok KT, Kan YY, Yang CF. Computed tomography in the diagnosis of organic bowel obstruction. Zhonghua Yi Xue Za Zhi (Taipei) 1996; 58:108-113. [PMID: 8915113] [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: 05/22/2023]
Abstract
BACKGROUND This study examined the usefulness of computed tomography (CT) scan for cases of organic intestinal obstruction, with two simple criteria. METHODS One hundred and thirteen patients with clinical suspicion of bowel obstruction were referred for CT scans. A line was drawn between the dilated proximal, and the collapsed distal bowels. A careful search was conducted on this line for obstructive lesions. The results were reported to be organic obstruction if there was an abrupt change of caliber (Criterion I) or a soft tissue mass around the dilated bowel (Criterion II). The judgement based on the CT findings. RESULTS Eighty-eight cases proved to have bowel obstruction. With Criterion I, the sensitivity was 59.1%, and specificity, 88% with Criterion II, the sensitivity was 56.3% and specificity 100%. If either of them was considered to be a positive sign of organic obstruction, the sensitivity was 100%, the specificity 88% and the accuracy 97.3%. The nature of the obstructions were precisely predicted in 76 patients (86%). CONCLUSIONS With these two simple criteria, CT scan can achieve high accuracy and is a recommendation in virtually every instance when intestinal obstruction is suspected.
Collapse
Affiliation(s)
- H B Pan
- Department of Radiology, Veterans General Hospital-Kaohsiung, Kaohsiung, R.O.C
| | | | | | | | | | | | | |
Collapse
|
29
|
|
30
|
Conley TR, Shih MC. Effects of light and chloroplast functional state on expression of nuclear genes encoding chloroplast glyceraldehyde-3-phosphate dehydrogenase in long hypocotyl (hy) mutants and wild-type Arabidopsis thaliana. Plant Physiol 1995; 108:1013-1022. [PMID: 7630933 PMCID: PMC157451 DOI: 10.1104/pp.108.3.1013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
In a previous study of Arabidopsis thaliana (J. Dewdney, T.R. Conley, M.-C. Shih, H.M. Goodman [1993] Plant Physiol 103: 1115-1121), it was postulated that both blue light receptor- and phytochrome-mediated pathways contribute to regulation of the nuclear genes encoding A and B subunits of glyceraldehyde-3-phosphate dehydrogenase (GAPA and GAPB). Here were report on the involvement of a nuclear gene encoding a putative blue-light receptor (HY4) and of a nuclear gene encoding phytochrome A apoprotein (PHYA) in regulation of the GAPA and GAPB genes in response to blue and far-red light. Continuous light irradiation experiments with the hy4 mutant demonstrate that the HY4 gene product is required for full expression of GAPA, GAPB, and one or more of the nuclear genes encoding small subunits of of ribulose-1,5-bisphosphate carboxylase/oxygenase. Continuous light irradiation and fluence-response studies with the phyA-101 mutant show that phytochrome A functions in far-red light regulation of GAPA, GAPB, nuclear genes encoding small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase, and CAB genes. Phytochromes A and B alone either do not participate in red light-mediated gene regulation or have redundant functions, as shown by analysis of phyA-101 and phyB-1 single mutants. In addition, the hypothesis that chloroplast-nucleus interactions affect GAPA and GAPB gene regulation was tested. Herbicide-mediated photooxidative damage to chloroplasts in A thaliana seedlings strongly decreased the maximum amount of GAPA and GAPB steady-state mRNA detected in continuous-light irradiation experiments. Full expression of the GAPB genes is dependent on the presence of functional chloroplasts.
Collapse
Affiliation(s)
- T R Conley
- Department of Biological Sciences, University of Iowa, Iowa City 52242, USA
| | | |
Collapse
|
31
|
Abstract
We have developed a rapid and simple method to detect the relation between HLA-DQ beta 57 Asp and Chinese IDDM patients. The method involved the selective amplification of a DNA fragment from the HLA-DQ B1 gene by using the mutagenic primers. After PCR, if the HLA-DQ beta 57 was Asp, then there was an artificially created restriction enzyme cutting site. We then can accurately obtain the results by enzyme digestion and electrophoresis. Sixty-nine IDDM patients and 30 nondiabetic control subjects were analyzed using this method. Twenty-two (42%) IDDM patients had non-Asp 57 homozygous, 31/45%) were Asp/non-Asp 57 heterozygous, and 9 (13%) had Asp-57 homozygous. Of the 30 control subjects, the number of cases for these three types were 6 (20%), 18 (60%), and 6 (20%), respectively. The relative risk of homozygous DQ beta 57 non-Asp in our group was 2.9 and the p value was greater than 0.05. Using this kind of approach, we were able to provide a simple, rapid, and non-radioactive method to detect whether the HLA DQ beta 57 was Asp or not.
Collapse
Affiliation(s)
- Y W Huang
- Department of Molecular Medicine and Clinical Pathology, Taipai Municipal Jen-Ai Hospital, Taiwan
| | | | | | | | | | | |
Collapse
|
32
|
Kwon HB, Park SC, Peng HP, Goodman HM, Dewdney J, Shih MC. Identification of a light-responsive region of the nuclear gene encoding the B subunit of chloroplast glyceraldehyde 3-phosphate dehydrogenase from Arabidopsis thaliana. Plant Physiol 1994; 105:357-67. [PMID: 8029358 PMCID: PMC159364 DOI: 10.1104/pp.105.1.357] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We report here the identification of a cis-acting region involved in light regulation of the nuclear gene (GapB) encoding the B subunit of chloroplast glyceraldehyde 3-phosphate dehydrogenase from Arabidopsis thaliana. Our results show that a 664-bp GapB promoter fragment is sufficient to confer light induction and organ-specific expression of the Escherichia coli beta-glucuronidase reporter gene (Gus) in transgenic tobacco (Nicotiana tabacum) plants. Deletion analysis indicates that the -261 to -173 upstream region of the GapB gene is essential for light induction. This region contains four direct repeats with the consensus sequence 5'-ATGAA(A/G)A-3' (Gap boxes). Deletion of all four repeats abolishes light induction completely. In addition, we have linked a 109-bp (-263 to -152) GapB upstream fragment containing the four direct repeats in two orientations to the -92 to +6 upstream sequence of the cauliflower mosaic virus 35S basal promoter. The resulting chimeric promoters are able to confer light induction and to enhance leaf-specific expression of the Gus reporter gene in transgenic tobacco plants. Based on these results we conclude that Gap boxes are essential for light regulation and organ-specific expression of the GapB gene in A. thaliana. Using gel mobility shift assays we have also identified a nuclear factor from tobacco that interacts with GapA and GapB DNA fragments containing these Gap boxes. Competition assays indicate that Gap boxes are the binding sites for this factor. Although this binding activity is present in nuclear extracts from leaves and roots of light-grown or dark-treated tobacco plants, the activity is less abundant in nuclear extracts prepared from leaves of dark-treated plants or from roots of greenhouse-grown plants. In addition, our data show that this binding factor is distinct from the GT-1 factor, which binds to Box II and Box III within the light-responsive element of the RbcS-3A gene of pea.
Collapse
Affiliation(s)
- H B Kwon
- Department of Biological Sciences, University of Iowa, Iowa City 52242
| | | | | | | | | | | |
Collapse
|
33
|
Conley TR, Park SC, Kwon HB, Peng HP, Shih MC. Characterization of cis-acting elements in light regulation of the nuclear gene encoding the A subunit of chloroplast isozymes of glyceraldehyde-3-phosphate dehydrogenase from Arabidopsis thaliana. Mol Cell Biol 1994; 14:2525-33. [PMID: 8139555 PMCID: PMC358620 DOI: 10.1128/mcb.14.4.2525-2533.1994] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [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: 01/29/2023] Open
Abstract
We have characterized cis-acting elements involved in light regulation of the nuclear gene (GapA) encoding the A subunit of chloroplast glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in Arabidopsis thaliana. Our results show that a 1.1-kb promoter fragment of the GapA gene is sufficient to confer light inducibility and organ specificity in transgenic Nicotiana tabacum (tobacco) plants, using the beta-glucuronidase gene of Escherichia coli as the reporter gene. Deletion analysis indicates that the -359 to -110 bp region of the GapA gene is necessary for light responsiveness. Within this region there are three copies of a decamer repeat (termed the Gap box) having the consensus sequence 5'-CAAATGAA(A/G)A-3', which has not been characterized in the promoter regions of other light-regulated genes. A deletion (to -247) producing loss of one copy of these elements from the GapA promoter reduces light induction by two- to threefold compared with a promoter deletion (to -359) with all three Gap boxes present, while deletion of all three Gap boxes (to -110) abolishes light induction completely. Gel mobility shift experiments using tobacco nuclei as the source of nuclear proteins show that GapA promoter fragments that contain these repeats bind strongly to a factor in the nuclear extract and that binding can be abolished by synthetic competitors consisting only of a monomer or dimer of the Gap box. Furthermore, a trimer, dimer, and monomer of the Gap box show binding activity and, like the authentic GapA promoter-derived probes, show binding activities that are correlated with Gap box copy number. These results strongly suggest that these repeats play important roles in light regulation of the GapA gene of A. thaliana.
Collapse
Affiliation(s)
- T R Conley
- Department of Biological Sciences, University of Iowa, Iowa City 52242
| | | | | | | | | |
Collapse
|
34
|
Shih MC. Cloning and sequencing of a cDNA clone encoding the cytosolic triose-phosphate isomerase from Arabidopsis thaliana. Plant Physiol 1994; 104:1103-4. [PMID: 8165257 PMCID: PMC160721 DOI: 10.1104/pp.104.3.1103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Affiliation(s)
- M C Shih
- Department of Biological Sciences, University of Iowa, Iowa City 52242
| |
Collapse
|
35
|
Dewdney J, Conley TR, Shih MC, Goodman HM. Effects of blue and red light on expression of nuclear genes encoding chloroplast glyceraldehyde-3-phosphate dehydrogenase of Arabidopsis thaliana. Plant Physiol 1993; 103:1115-21. [PMID: 8290625 PMCID: PMC159096 DOI: 10.1104/pp.103.4.1115] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We have characterized the effects of different light spectra on expression of the nuclear genes (GapA and GapB) encoding chloroplast glyceraldehyde-3-phosphate dehydrogenase in Arabidopsis thaliana. Steady-state mRNA levels for both genes in etiolated seedlings increased after a short exposure to red or blue light. However, these increases could not be reversed by immediate far-red light following the initial light treatment. In mature plants, a short light pulse, regardless of its spectrum, had no apparent effect on GapA or GapB mRNA levels in dark-adapted plants. In contrast, continuous exposure to red, blue, or white light resulted in increases of GapA and GapB mRNA levels, with blue and white light being far more efficient than red light. Similarly, continuous exposure of etiolated seedlings to red, blue, or white light also resulted in increased GapA and GapB mRNA levels. In addition, we show that illumination of red light-saturated Arabidopsis plants with continuous blue light results in further increases of GapA and GapB mRNA levels. Based on these results, we conclude that both blue light photoreceptor- and phytochrome-mediated pathways are involved in light regulation of GapA and GapB genes in Arabidopsis, with blue light acting as the dominant regulator.
Collapse
Affiliation(s)
- J Dewdney
- Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston 02114
| | | | | | | |
Collapse
|
36
|
Yang Y, Kwon HB, Peng HP, Shih MC. Stress responses and metabolic regulation of glyceraldehyde-3-phosphate dehydrogenase genes in Arabidopsis. Plant Physiol 1993; 101:209-16. [PMID: 8278495 PMCID: PMC158666 DOI: 10.1104/pp.101.1.209] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We report here effects of three environmental conditions, heat shock, anaerobic treatment, and carbon source supply, on expression of nuclear genes encoding chloroplast (GapA and GapB) and cytosolic (GapC) glyceraldehyde-3-phosphate dehydrogenase from Arabidopsis thaliana. The steady-state mRNA level of the GapC increased when Arabidopsis plants were transferred from normal growth condition to heat-shock, anaerobiosis, or increased sucrose supply conditions. In contrast, the steady-state mRNA levels for GapA and GapB genes were unaffected or decreased transiently under the same treatments. To identify the cis-acting regulatory elements, transgenic tobacco plants containing a 820-bp GapC 5'-flanking DNA fragment and beta-glucuronidase (Gus) fusion were constructed. Analyses of these transgenic plants indicate that this 820-bp DNA fragment is sufficient to confer both heat-shock and anaerobic responses. These results suggest that transcriptional level control is involved in regulation of GapC expression under these stress conditions. Histochemical analysis of Gus activity indicates that expression of the GapC is cell-type specific and is probably linked to the metabolic activity of the cells.
Collapse
Affiliation(s)
- Y Yang
- Department of Biological Sciences, University of Iowa, Iowa City 52242
| | | | | | | |
Collapse
|
37
|
Shih MC, Heinrich P, Goodman HM. Cloning and chromosomal mapping of nuclear genes encoding chloroplast and cytosolic glyceraldehyde-3-phosphate-dehydrogenase from Arabidopsis thaliana. Gene 1992; 119:317-9. [PMID: 1398114 DOI: 10.1016/0378-1119(92)90290-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- M C Shih
- Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston
| | | | | |
Collapse
|
38
|
Shih MC, Bohanon TM, Mikrut JM, Zschack P, Dutta P. X-ray-diffraction study of the superliquid region of the phase diagram of a Langmuir monolayer. Phys Rev A 1992; 45:5734-5737. [PMID: 9907672 DOI: 10.1103/physreva.45.5734] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
39
|
Shih MC, Heinrich P, Goodman HM. Cloning and chromosomal mapping of nuclear genes encoding chloroplast and cytosolic glyceraldehyde-3-phosphate-dehydrogenase from Arabidopsis thaliana. Gene 1991; 104:133-8. [PMID: 1916285 DOI: 10.1016/0378-1119(91)90242-4] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Both cDNA and genomic clones for the nuclear genes encoding chloroplast (cp) (gapA and gapB) and cytosolic (gapC) glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from Arabidopsis thaliana have been isolated and characterized. Genomic Southern-blot analyses indicate that there is only one copy of each gapA, gapB and gapC gene in A. thaliana. Comparison of the deduced amino acid (aa) sequences shows that the A and B subunits are highly similar (80% positional aa identity), while there is less similarity between the cp and cytosolic subunits (45% aa identity). These relationships are consistent with the idea that the cp and cytosolic GAPDHs evolved from different lineages, as suggested in our previous study of tobacco GAPDHs [Shih et al., Cell 47 (1986) 73-80]. In addition, the chromosomal locations for the three gap genes were determined by restriction fragment length polymorphism mapping; the three gap genes are not closely linked, gapA (55.8 cM) and gapC (0.0 cM) are on chromosome 3, and gapB (51.3 cM) is on chromosome 1.
Collapse
Affiliation(s)
- M C Shih
- Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston 02114
| | | | | |
Collapse
|
40
|
|
41
|
Bohanon TM, Lin B, Shih MC, Ice GE, Dutta P. Determination of lattice structure and calculation of molecular tilt in lipid monolayers on water using x-ray diffraction. Phys Rev B Condens Matter 1990; 41:4846-4849. [PMID: 9994335 DOI: 10.1103/physrevb.41.4846] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
42
|
Wang TC, Shih MC, Markey SP, Duncan MW. Quantitative analysis of low molecular weight polar compounds by continuous flow liquid secondary ion tandem mass spectrometry. Anal Chem 1989; 61:1013-6. [PMID: 2786352 DOI: 10.1021/ac00184a019] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Quantitative analyses of low molecular weight (100-200) polar compounds [1-methyl-4-phenylpyridine (MPP+), 2-amino-3-(methylamino)propanoic acid (synonyms, beta-(methyl-amino)-L-alanine or BMAA), and tryptophan] were conducted on a triple-stage quadrupole mass spectrometer configured for continuous flow liquid secondary ion mass spectrometry ionization (CF L-SIMS). It is shown that quantification by CF L-SIMS at subnanogram sensitivity can be precise (correlation coefficients greater than 0.99), accurate, specific, and routine for compounds not measurable by static L-SIMS. Successful analyses, however, are strongly dependent upon the stability of the film formed by the mobile phase on the probe tip. In our system, film stability is affected by mobile phase composition and flow rate, ion source and probe tip temperature, probe-tip and capillary alignment, film thickness, and sample composition.
Collapse
|
43
|
Abstract
Nucleotide sequences for the nuclear genes encoding chloroplast (GapA and GapB) and cytosolic (GapC) glyceraldehyde-3-phosphate dehydrogenases (GAPDHs) from Arabidopsis thaliana were determined. Comparison of nucleotide sequences indicates that the divergence of chloroplast and cytosolic GAPDH genes preceded the divergence of prokaryotes and eukaryotes. In addition, some intron-exon junctions are conserved among GapB, GapC, and chicken GAPDH genes. These results provide evidence at the molecular level to support the idea that introns existed before the divergence of prokaryotes and eukaryotes.
Collapse
Affiliation(s)
- M C Shih
- Department of Genetics, Harvard Medical School, Boston, MA
| | | | | |
Collapse
|
44
|
Shih MC, Goodman HM. Differential light regulated expression of nuclear genes encoding chloroplast and cytosolic glyceraldehyde-3-phosphate dehydrogenase in Nicotiana tabacum. EMBO J 1988; 7:893-8. [PMID: 16453834 PMCID: PMC454413 DOI: 10.1002/j.1460-2075.1988.tb02893.x] [Citation(s) in RCA: 32] [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] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
When tobacco (Nicotiana tabacum) plants were transferred from the dark to continuous white light, the steady-state mRNA levels transcribed from the nuclear genes encoding chloroplast (GapA and GapB) glyceraldehyde-3-phosphate dehydrogenase increased at least 30- to 50-fold, while the mRNA level for the cytosolic enzyme (GapC) increased only 10-fold. Kinetic analyses show that the rates of mRNA accumulation for GapA and GapB are identical reaching steady-state levels after 24-48 h in light. In contrast, mRNA accumulation for the GapC gene shows a completely different kinetic pattern, accumulating much faster than that of GapA and GapB. These results suggest that expression of GapC and GapA/B genes are controlled by different light regulated mechanisms and nuclear run-on analyses suggest that these effects are primarily due to increased transcription.
Collapse
Affiliation(s)
- M C Shih
- Department of Genetics, Harvard Medical School, Boston, MA 02114, USA
| | | |
Collapse
|
45
|
Bojkowski CJ, Arendt J, Shih MC, Markey SP. Melatonin secretion in humans assessed by measuring its metabolite, 6-sulfatoxymelatonin. Clin Chem 1987; 33:1343-8. [PMID: 3608151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Comparing a direct radioimmunoassay for 6-sulfatoxymelatonin (aMT6s) with an established gas chromatographic/mass spectrometric method for 6-hydroxymelatonin, we found a good correlation r = 0.94 (P less than 0.001, n = 100). aMT6s was stable, both in urine and plasma samples, without preservative, for at least two years at -20 degrees C and for five days at room temperature. Urinary excretion of aMT6s showed considerable inter-individual differences; however, the aMT6s excretion of any one individual was consistent over a four-day period, as assessed by continuous collection from 18 normal volunteers. Total 24-h urinary excretion of aMT6s was significantly correlated with the area under the curve of the respective profiles for plasma melatonin (r = 0.75, P = 0.0002) and plasma aMT6s (r = 0.70, P = 0.0005) for 22 healthy volunteers. At 24:00 h and 03:00 h, sampling plasma at 30-s intervals provided no evidence for episodic secretion (in short pulses) of either melatonin or aMT6s.
Collapse
|
46
|
Shih MC, Lazar G, Goodman HM. Evidence in favor of the symbiotic origin of chloroplasts: primary structure and evolution of tobacco glyceraldehyde-3-phosphate dehydrogenases. Cell 1986; 47:73-80. [PMID: 3757034 DOI: 10.1016/0092-8674(86)90367-3] [Citation(s) in RCA: 135] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
We report nucleotide sequences of cDNAs for the nuclear genes encoding chloroplast (GapA and GapB) and cytosolic (GapC) glyceraldehyde-3-phosphate dehydrogenases (GAPDH) from N. tabacum. Comparison of nucleotide sequences indicates that the GapA and GapB genes evolved following duplication of an ancestral gene about 450 million years ago. However, the divergence of GapA/B and GapC occurred much earlier in evolution than the divergence of GapC and GAPDH genes of animals and fungi, suggesting that chloroplast and cytosolic GAPDHs evolved from different lineages. Comparison of amino acid sequences shows that the chloroplast GAPDHs are related to GAPDHs found in thermophilic bacteria, while the cytosolic GAPDH is related to the GAPDH found in mesophilic prokaryotes. These results strongly support the symbiotic origin of chloroplasts.
Collapse
|
47
|
Shih MC, Markey SP. Quantification of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and 1-methyl-4-phenylpyridinium ion in brain tissue by gas chromatography/mass spectrometry. Biomed Environ Mass Spectrom 1986; 13:85-9. [PMID: 2937483 DOI: 10.1002/bms.1200130207] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A sensitive gas chromatographic/mass spectrometric assay has been developed to quantify 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 1-methyl-4-phenylpyridinium ion (MPP+) in brain tissue. MPTP was derivatized with isobutyl chloroformate and then analyzed using gas chromatography/mass spectrometry. MPP+, a known metabolite of MPTP, was reduced with NaB2H4 to 2H2-MPTP before derivatization. Deuterated isotopomers of MPTP and MPP+ were used as internal standards. The intra-assay coefficients of variation in the determination of 57.3 ng MPTP and 371.8 ng MPP+ in 100 mg of mouse brain tissue were 3.0% and 5.6% (n = 7), respectively. The detection limit corresponds to about 2 ng per sample of authentic MPTP.
Collapse
|
48
|
Place N, Fien K, Mahoney ME, Wulff DL, Ho YS, Debouck C, Rosenberg M, Shih MC, Gussin GN. Mutations that alter the DNA binding site for the bacteriophage lambda cII protein and affect the translation efficiency of the cII gene. J Mol Biol 1984; 180:865-80. [PMID: 6241264 DOI: 10.1016/0022-2836(84)90261-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The efficiency of translation of the cII gene of bacteriophage lambda is greatly reduced by the cII3059 mutation, a GUU----GAU (Val----Asp) change in the second cII codon. Mutations in the third and fourth codons of the cII gene, called ctr mutations, reverse this translation deficiency. Lambda cII3059 ctr-1, which has a GCA----ACA (Ala----Thr) change in the fourth cII codon, produces about half the normal level of cII activity in liquid cultures, and lambda cII3059 ctr-2 and lambda cII3059 ctr-3, which have identical CGT----CGC changes in the third codon, produce normal levels of cII activity in liquid culture. Since the cII protein of ctr-3 has the same primary sequence as that of lambda cII3059, the cII- phenotype of lambda cII3059 can be explained entirely by the deficiency of translating cII mRNA. We propose that ctr mutations increase translation efficiency by destabilizing a stable stem structure which can be formed by cII mRNA. The ctr mutations lie in an overlapping regulatory region which contains, in addition to sequence elements that influence the rate of cII translation, a region to which cII protein binds to activate transcription from the PRE promoter. The ctr-1 mutation alters the cII recognition sequence from 5'-T-T-G-C-N6T-T-G-C-3' to 5'-T-T-G-C-N6T-T-G-T-3', but has no effect on PRE activity. Since a C----T change in the first (5'-proximal) T-T-G-C sequence (to yield 5'-T-T-G-T-N6T-T-G-C) greatly lowers cII binding affinity, cII protein must not recognize the two T-T-G-C sequences in an identical manner.
Collapse
|
49
|
Shih MC, Gussin GN. Kinetic analysis of mutations affecting the cII activation site at the PRE promoter of bacteriophage lambda. Proc Natl Acad Sci U S A 1984; 81:6432-6. [PMID: 6238332 PMCID: PMC391938 DOI: 10.1073/pnas.81.20.6432] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Abortive initiation and run-off transcription assays were used to study the effects of cy mutations on activation of the phage lambda PRE promoter by cII gene product. Six point mutations in the repeated T-T-G-C sequences that flank the -35 consensus region of PRE decreased the apparent affinity of the promoter for cII protein by factors of 4-16 relative to the wild-type affinity. Kinetic analyses of transcription initiation in the presence and absence of cII protein demonstrated that five of the six mutations did not significantly affect the intrinsic interaction of RNA polymerase with PRE. Thus, these mutations differ from other cy mutations, including those in the -35 consensus region, which affect the formation of polymerase-PRE closed complexes or the isomerization of closed complexes to open complexes but do not affect the binding of cII protein. A sixth T-T-G-C mutation, cy3001, may affect intrinsic initiation by RNA polymerase as well as cII binding.
Collapse
|
50
|
Shih MC, Gussin GN. Role of cII protein in stimulating transcription initiation at the lambda PRE promoter. Enhanced formation and stabilization of open complexes. J Mol Biol 1984; 172:489-506. [PMID: 6229641 DOI: 10.1016/s0022-2836(84)80019-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Abortive and productive initiation assays were used to study transcription initiation at the PRE promoter of phage lambda in vitro. Two parameters were measured: k2, the rate constant for the transition between closed and open complexes; and KB, the equilibrium constant for the initial binding of RNA polymerase to promoter DNA. In the absence of cII protein (which activates PRE) the PRE promoter was extremely weak as expected, with k2 = 4.0 X 10(-4) S-1 and KB = 1.0 X 10(7) M-1. The addition of cII protein resulted in about a 15-fold increase in KB and a 40-fold increase in k2. Thus, cII activation of PRE results both in enhanced binding of RNA polymerase to DNA to form closed complexes and in an enchanced rate of isomerization of closed to open complexes. In addition, we found that open complexes formed in the presence of cII protein were at least four times as stable as those formed in its absence. This suggests that RNA polymerase and cII protein may remain in close contact even after complexes are formed.
Collapse
|