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Clausen L, Larsen JT, Bulik CM, Petersen L. A Danish register-based study on involuntary treatment in anorexia nervosa. Int J Eat Disord 2018; 51:1213-1222. [PMID: 30414329 DOI: 10.1002/eat.22968] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 09/20/2018] [Accepted: 09/20/2018] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Involuntary treatment is controversial and widely debated, but remains a significant component of treatment for severe anorexia nervosa. Given how little is known about this topic, we describe the frequency of various involuntary measures in a national cohort of all patients diagnosed with anorexia nervosa. In a subsample of patients, we explored predictors of the first involuntary measure recorded. METHOD Descriptive statistics and Cox proportional hazard analyses were conducted using the national registers of Denmark covering the total population. Data from the National Patient Register and the Psychiatric Central Research Register including all psychiatric visits from 1969 onwards were merged with data from the National Register on Coercion covering 1999 onward. Involuntary measures registered between 2000 and 2013 were analyzed. RESULTS A total of 4,727 patients with a diagnosis of anorexia nervosa representing 16,592 admissions were included. Eighteen percent experienced at least one involuntary measure. A variety of measures were used with tube feeding being the most frequent followed by mechanical restraint, involuntary medication, physical restraint, constant observation, and sedative medication. A subsample of 2% of AN patients had more than 100 involuntary measures recorded. The first recorded involuntary measure was predicted by most but not all psychiatric comorbidities, especially schizophrenia, autism spectrum, and personality disorders, older age at first diagnosis, and previous admissions. DISCUSSION It is important to develop a more granular understanding of patients at risk of requiring involuntary treatment and to determine how best to treat them effectively with minimal use of involuntary measures.
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Affiliation(s)
- L Clausen
- Centre for Child and Adolescent Psychiatry, Aarhus University Hospital Risskov, Risskov, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Psychology and Behavioural Sciences, Aarhus University, Aarhus, Denmark
| | - J T Larsen
- National Centre for Register-Based Research, Aarhus BSS, Aarhus University, Aarhus, Denmark.,Lundbeck Foundation Initiative for Integrative Psychiatric Research (iPSYCH), Aarhus University, Aarhus, Denmark
| | - C M Bulik
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Department of Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - L Petersen
- National Centre for Register-Based Research, Aarhus BSS, Aarhus University, Aarhus, Denmark.,Lundbeck Foundation Initiative for Integrative Psychiatric Research (iPSYCH), Aarhus University, Aarhus, Denmark
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Rimvall MK, Clemmensen L, Munkholm A, Rask CU, Larsen JT, Skovgaard AM, Simons CJP, van Os J, Jeppesen P. Introducing the White Noise task in childhood: associations between speech illusions and psychosis vulnerability. Psychol Med 2016; 46:2731-2740. [PMID: 27444712 DOI: 10.1017/s0033291716001112] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Auditory verbal hallucinations (AVH) are common during development and may arise due to dysregulation in top-down processing of sensory input. This study was designed to examine the frequency and correlates of speech illusions measured using the White Noise (WN) task in children from the general population. Associations between speech illusions and putative risk factors for psychotic disorder and negative affect were examined. METHOD A total of 1486 children aged 11-12 years of the Copenhagen Child Cohort 2000 were examined with the WN task. Psychotic experiences and negative affect were determined using the Kiddie-SADS-PL. Register data described family history of mental disorders. Exaggerated Theory of Mind functioning (hyper-ToM) was measured by the ToM Storybook Frederik. RESULTS A total of 145 (10%) children experienced speech illusions (hearing speech in the absence of speech stimuli), of which 102 (70%) experienced illusions perceived by the child as positive or negative (affectively salient). Experiencing hallucinations during the last month was associated with affectively salient speech illusions in the WN task [general cognitive ability: adjusted odds ratio (aOR) 2.01, 95% confidence interval (CI) 1.03-3.93]. Negative affect, both last month and lifetime, was also associated with affectively salient speech illusions (aOR 2.01, 95% CI 1.05-3.83 and aOR 1.79, 95% CI 1.11-2.89, respectively). Speech illusions were not associated with delusions, hyper-ToM or family history of mental disorders. CONCLUSIONS Speech illusions were elicited in typically developing children in a WN-test paradigm, and point to an affective pathway to AVH mediated by dysregulation in top-down processing of sensory input.
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Affiliation(s)
- M K Rimvall
- Child and Adolescent Mental Health Center,Mental Health Services,The Capital Region of Denmark,Glostrup,Denmark
| | - L Clemmensen
- Child and Adolescent Mental Health Center,Mental Health Services,The Capital Region of Denmark,Glostrup,Denmark
| | - A Munkholm
- Child and Adolescent Mental Health Center,Mental Health Services,The Capital Region of Denmark,Glostrup,Denmark
| | - C U Rask
- Child and Adolescent Psychiatric Centre Risskov,Aarhus University Hospital,Aarhus,Denmark
| | - J T Larsen
- The National Centre for Register-based Research,Aarhus University,Aarhus,Denmark
| | - A M Skovgaard
- Department of Public Health,University of Copenhagen,Copenhagen,Denmark
| | - C J P Simons
- Department of Psychiatry and Psychology,Maastricht University Medical Centre,Maastricht,The Netherlands
| | - J van Os
- Department of Psychiatry and Psychology,Maastricht University Medical Centre,Maastricht,The Netherlands
| | - P Jeppesen
- Child and Adolescent Mental Health Center,Mental Health Services,The Capital Region of Denmark,Glostrup,Denmark
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Ravi P, Kumar S, Larsen JT, Gonsalves W, Buadi F, Lacy MQ, Go R, Dispenzieri A, Kapoor P, Lust JA, Dingli D, Lin Y, Russell SJ, Leung N, Gertz MA, Kyle RA, Bergsagel PL, Rajkumar SV. Evolving changes in disease biomarkers and risk of early progression in smoldering multiple myeloma. Blood Cancer J 2016; 6:e454. [PMID: 27471870 PMCID: PMC5030386 DOI: 10.1038/bcj.2016.65] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 06/23/2016] [Indexed: 01/07/2023] Open
Abstract
We studied 190 patients with smoldering multiple myeloma (SMM) at our institution between 1973 and 2014. Evolving change in monoclonal protein level (eMP) was defined as ⩾10% increase in serum monoclonal protein (M) and/or immunoglobulin (Ig) (M/Ig) within the first 6 months of diagnosis (only if M-protein ⩾3 g/dl) and/or ⩾25% increase in M/Ig within the first 12 months, with a minimum required increase of 0.5 g/dl in M-protein and/or 500 mg/dl in Ig. Evolving change in hemoglobin (eHb) was defined as ⩾0.5 g/dl decrease within 12 months of diagnosis. A total of 134 patients (70.5%) progressed to MM over a median follow-up of 10.4 years. On multivariable analysis adjusting for factors known to predict for progression to MM, bone marrow plasma cells ⩾20% (odds ratio (OR)=3.37 (1.30-8.77), P=0.013), eMP (OR=8.20 (3.19-21.05), P<0.001) and eHb (OR=5.86 (2.12-16.21), P=0.001) were independent predictors of progression within 2 years of SMM diagnosis. A risk model comprising these variables was constructed, with median time to progression of 12.3, 5.1, 2.0 and 1.0 years among patients with 0-3 risk factors respectively. The 2-year progression risk was 81.5% in individuals who demonstrated both eMP and eHb, and 90.5% in those with all three risk factors.
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Affiliation(s)
- P Ravi
- Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - S Kumar
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - J T Larsen
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - W Gonsalves
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - F Buadi
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - M Q Lacy
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - R Go
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - A Dispenzieri
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - P Kapoor
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - J A Lust
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - D Dingli
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - Y Lin
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - S J Russell
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - N Leung
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - M A Gertz
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - R A Kyle
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
| | - P L Bergsagel
- Division of Hematology and Oncology, Mayo Clinic Arizona, Scottsdale, AZ, USA
| | - S V Rajkumar
- Division of Hematology, Mayo Clinic, Rochester, MN, USA
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Koch SV, Larsen JT, Mouridsen SE, Bentz M, Petersen L, Bulik C, Mortensen PB, Plessen KJ. Autism Spectrum Disorders in Patients with Anorexia Nervosa and in their First- and Second-Degree Relatives—a Danish Nationwide Register-Based Cohort-Study. Int J Epidemiol 2015. [DOI: 10.1093/ije/dyv097.005] [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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Larsen JT, McGraw AP, Cacioppo JT. Can people feel happy and sad at the same time? J Pers Soc Psychol 2001; 81:684-96. [PMID: 11642354] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
The authors investigated whether people can feel happy and sad at the same time. J. A. Russell and J. M. Carroll's (1999) circumplex model holds that happiness and sadness are polar opposites and, thus, mutually exclusive. In contrast, the evaluative space model (J. T. Cacioppo & G. G. Berntson, 1994) proposes that positive and negative affect are separable and that mixed feelings of happiness and sadness can co-occur. The authors both replicated and extended past research by showing that whereas most participants surveyed in typical situations felt either happy or sad, many participants surveyed immediately after watching the film Life Is Beautiful, moving out of their dormitories, or graduating from college felt both happy and sad. Results suggest that although affective experience may typically be bipolar, the underlying processes, and occasionally the resulting experience of emotion, are better characterized as bivariate.
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Affiliation(s)
- J T Larsen
- Department of Psychology, The Ohio State University, USA
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Larsen JT, Clemensen SV, Klitgaard NA, Nielsen B, Brøsen K. [Clozapine-induced toxic hepatitis]. Ugeskr Laeger 2001; 163:2013-4. [PMID: 11307364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
A case of clozapine-induced toxic hepatitis in a 49-year old woman with schizophrenia is described. The daily clozapine dose was clinically titrated to 300 mg. Subsequently, the patient experienced lethargy and anorexia, and fever, eosinophilia, leucocytosis and abnormal liver parameters were found. The serum concentration of clozapine was 8595 nmol/l, and treatment was discontinued. After eight days, the condition stabilised, and low-dose clozapine treatment was successfully reinstituted with serum monitoring (TDM).
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Affiliation(s)
- J T Larsen
- Odense Universitetshospital, afdeling KKA, sektion for klinisk farmakologi og psykiatrisk afdeling P
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Abstract
AIMS The aim of the present study was to examine the CYP1A2 substrate tacrine as a possible alternative to caffeine for assessing CYP1A2 activity in vivo. METHODS Eighteen, healthy, nonsmoking men participated. Each volunteer was tested by caffeine (200 mg orally), and caffeine metabolic ratios were calculated. Subsequently, on two occasions, separated by at least 4 weeks, each volunteer was tested with tacrine (40 mg orally). The apparent oral clearance, partial clearances and different metabolic ratios of tacrine were determined. RESULTS The median oral clearances of tacrine in the two study periods were 1893 l h-1 (range: 736-3098) and 1890 l h-1 (range: 438-4175), respectively. The interindividual coefficient of variation was 42% and 49%, respectively. The intraindividual coefficients of variation ranged from 0.28% to 64% (median: 13%). In both study periods, the oral clearance of tacrine correlated with the caffeine urinary metabolic ratio. However, only modest magnitudes of correlation were observed (rs: 0.64-0.66, P<0. 01). No tacrine metabolic ratio correlating with the oral clearance of tacrine was found. Conclusion The applicability of tacrine as a probe drug for measuring CYP1A2 activity in vivo appears limited.
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Affiliation(s)
- J T Larsen
- Institute of Public Health, Clinical Pharmacology, University of Southern Denmark, Main Campus: Odense University, Denmark
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Abstract
OBJECTIVE In vitro studies have shown that tacrine is metabolized by cytochrome P4501A2 (CYP1A2). One of the monohydroxy-metabolites has been incriminated with tacrine-induced hepatotoxicity. The aim of this study was to establish whether the potent CYP1A2 inhibitor fluvoxamine in clinically relevant doses could inhibit tacrine metabolism. METHODS Eighteen healthy young men were enrolled in an open, randomized crossover study. In the first study period a single oral dose of tacrine 40 mg was given. In the second period the volunteers were randomized to maintenance doses of fluvoxamine 50 or 100 mg per day, and a single oral dose of tacrine 20 mg was given. RESULTS Fluvoxamine was found to be a very potent inhibitor of tacrine metabolism. A fractional decrement in tacrine clearance of approximately 85% was found with both fluvoxamine doses, which was in good agreement with a prediction based on in vitro data. The medians of the steady-state concentration of fluvoxamine were 43 nM (range 25-49) and 70 nM (range 44-124) in the 50 mg per day and 100 mg per day groups, respectively. The steady-state concentration of fluvoxamine correlated with the fractional decrement in tacrine clearance (Spearman Rs = 0.53, P < 0.05). Modest, but statistically significant, reductions in the formation of the metabolites 1- and 2-hydroxytacrine were found during concomitant fluvoxamine treatment. CONCLUSION Fluvoxamine at clinically relevant doses is a potent inhibitor of tacrine metabolism. This interaction is very likely to have clinical relevance. Whether concomitant fluvoxamine treatment reduces tacrine-induced hepatotoxicity needs further study.
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Affiliation(s)
- J T Larsen
- Institute of Public Health, Clinical Pharmacology, University of Southern Denmark, Odense.
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Ito TA, Larsen JT, Smith NK, Cacioppo JT. Negative information weighs more heavily on the brain: the negativity bias in evaluative categorizations. J Pers Soc Psychol 1999. [PMID: 9825526 DOI: 10.1037//0022-3514.75.4.887] [Citation(s) in RCA: 229] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Negative information tends to influence evaluations more strongly than comparably extreme positive information. To test whether this negativity bias operates at the evaluative categorization stage, the authors recorded event-related brain potentials (ERPs), which are more sensitive to the evaluative categorization than the response output stage, as participants viewed positive, negative, and neutral pictures. Results revealed larger amplitude late positive brain potentials during the evaluative categorization of (a) positive and negative stimuli as compared with neutral stimuli and (b) negative as compared with positive stimuli, even though both were equally probable, evaluatively extreme, and arousing. These results provide support for the hypothesis that the negativity bias in affective processing occurs as early as the initial categorization into valence classes.
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Affiliation(s)
- T A Ito
- Department of Psychology, Ohio State University, Columbus 43210-1222, USA
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10
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Ito TA, Larsen JT, Smith NK, Cacioppo JT. Negative information weighs more heavily on the brain: the negativity bias in evaluative categorizations. J Pers Soc Psychol 1998; 75:887-900. [PMID: 9825526 DOI: 10.1037/0022-3514.75.4.887] [Citation(s) in RCA: 959] [Impact Index Per Article: 36.9] [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: 11/08/2022]
Abstract
Negative information tends to influence evaluations more strongly than comparably extreme positive information. To test whether this negativity bias operates at the evaluative categorization stage, the authors recorded event-related brain potentials (ERPs), which are more sensitive to the evaluative categorization than the response output stage, as participants viewed positive, negative, and neutral pictures. Results revealed larger amplitude late positive brain potentials during the evaluative categorization of (a) positive and negative stimuli as compared with neutral stimuli and (b) negative as compared with positive stimuli, even though both were equally probable, evaluatively extreme, and arousing. These results provide support for the hypothesis that the negativity bias in affective processing occurs as early as the initial categorization into valence classes.
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Affiliation(s)
- T A Ito
- Department of Psychology, Ohio State University, Columbus 43210-1222, USA
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Hansen LL, Larsen JT, Brøsen K. Determination of tacrine and its metabolites in human plasma and urine by high-performance liquid chromatography and fluorescence detection. J Chromatogr B Biomed Sci Appl 1998; 712:183-91. [PMID: 9698241 DOI: 10.1016/s0378-4347(98)00183-2] [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] [Indexed: 02/08/2023]
Abstract
A new method for the simultaneous quantitation of tacrine and the three metabolites, 1-hydroxytacrine (velnacrine, maleate), 2-hydroxytacrine and 4-hydroxytacrine, in human plasma and urine has been developed. The method was based on simple one-step liquid-liquid extraction with ethyl acetate followed by isocratic, reversed-phase high-performance liquid chromatography and fluorescence detection (excitation: 330 nm and emission: 365 nm). The limit of detection in plasma was 0.5 nM for 2-hydroxytacrine and 4-hydroxytacrine, 2 nM for 1-hydroxytacrine and tacrine. In urine it was 60 nM for 2-hydroxytacrine and 4-hydroxytacrine, 30 nM for 1-hydroxytacrine and 80 nM for tacrine. The limit of quantification in plasma was 2.5 nM for 2-hydroxytacrine and 4-hydroxytacrine, 10 nM for 1-hydroxytacrine and 2 nM for tacrine. In urine it was 120 nM for all components. The overall mean recoveries ranged from 84 to 105% in plasma and from 64 to 100% in urine for all four compounds.
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Affiliation(s)
- L L Hansen
- Department of Clinical Pharmacology, Institute of Medical Biology, Odense University, Denmark
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Carlsson J, Larsen JT, Edlund MB. Utilization of glutathione (L-gamma-glutamyl-L-cysteinylglycine) by Fusobacterium nucleatum subspecies nucleatum. Oral Microbiol Immunol 1994; 9:297-300. [PMID: 7808772 DOI: 10.1111/j.1399-302x.1994.tb00074.x] [Citation(s) in RCA: 19] [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] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Although fusobacteria use amino acids and peptides as energy source, it is not known whether they are able to actively transport peptides into the cell. In the present study the tripeptide glutathione was used as a model substance to investigate peptide uptake in Fusobacterium nucleatum subsp. nucleatum. Cells harvested after 2 days of growth on blood agar or in their exponential growth phase in broth were suspended in buffer with glutathione, L-cysteinylglycine and L-cysteine. As a measure of cell uptake, the formation of hydrogen sulfide was followed. Cells from blood agar had a low capacity to form hydrogen sulfide from the tripeptide glutathione and the dipeptide L-cysteinylglycine. However, hydrogen sulfide was formed from L-cysteinylglycine, but not from glutathione or from L-cysteine, by cells grown in broth in such a way that it strongly indicated an active transport of L-cysteinylglycine with a Km of 18 microM. Hydrogen sulfide was efficiently formed from glutathione by cells grown in broth in the presence 1 mM glutathione. In these cells a glycylglycine-dependent L-gamma-glutamyl peptidase activity was induced. It is probable that the efficient utilization of glutathione for hydrogen sulfide formation mirrored the uptake of L-cysteinylglycine after an L-gamma-glutamyl peptidase had split L-glutamate off from glutathione.
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Affiliation(s)
- J Carlsson
- Department of Oral Microbiology, University of Umeå, Sweden
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Osterheld AL, Morgan WL, Larsen JT, Young BK, Goldstein WH. Analysis of spectra from laser produced plasmas using a neural network. Phys Rev Lett 1994; 73:1505-1508. [PMID: 10056810 DOI: 10.1103/physrevlett.73.1505] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Abstract
There are high amounts of hydrogen sulfide in deep periodontal pockets. This volatile sulfur compound may be formed from L-cysteine, but only low levels of this amino acid can be expected to be present in periodontal pockets. Glutathione, L-gamma-glutamyl-L-cysteinylglycine, is in high concentration in most tissue cells, and this tripeptide may be more readily available as a source of hydrogen sulfide formation in the pockets. The ability of 37 different species of oral bacteria to utilize glutathione in hydrogen sulfide formation was studied. Of these species, only 2 species of Peptostreptococcus and 5 species of Fusobacterium formed high amounts of hydrogen sulfide from glutathione within 24 h. Since the initial rate of hydrogen sulfide formation was more than 5 times higher in Peptostreptococcus micros than in any of the other bacterial species, the kinetics of sulfide formation from glutathione by P. micros was further elucidated. The formation of sulfide followed quite closely hyperbolic Michaelis-Menten kinetics. The maximal initial rate of sulfide formation (Vmax) was 163 +/- 2 nmol sulfide per minute per milligram of cellular protein. Half maximal initial rate (Km) was obtained at 7.4 +/- 0.8 microM glutathione. The initial rate of sulfide formation from L-cysteine was much slower and was almost proportional to L-cysteine concentration. This difference in kinetics of sulfide formation between glutathione and L-cysteine strongly suggested that glutathione was actively transported into the cell, whereas the transport of L-cysteine was more or less controlled by diffusion. The sulfide formation from the dipeptide L-cysteinylglycine also followed quite closely hyperbolic Michaelis-Menten kinetics.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J Carlsson
- Department of Oral Microbiology, University of Umeå, Sweden
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Mountain HA, Byström AS, Larsen JT, Korch C. Four major transcriptional responses in the methionine/threonine biosynthetic pathway of Saccharomyces cerevisiae. Yeast 1991; 7:781-803. [PMID: 1789001 DOI: 10.1002/yea.320070804] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.6] [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: 12/28/2022] Open
Abstract
Genes encoding enzymes in the threonine/methionine biosynthetic pathway were cloned and used to investigate their transcriptional response to signals known to affect gene expression on the basis of enzyme specific-activities. Four major responses were evident: strong repression by methionine of MET3, MET5 and MET14, as previously described for MET3, MET2 and MET25; weak repression by methionine of MET6; weak stimulation by methionine but no response to threonine was seen for THR1, HOM2 and HOM3; no response to any of the signals tested, for HOM6 and MES1. In a BOR3 mutant, THR1, HOM2 and HOM3 mRNA levels were increased slightly. The stimulation of transcription by methionine for HOM2, HOM3 and THR1 is mediated by the GCN4 gene product and hence these genes are under the general amino acid control. In addition to the strong repression by methionine, MET5 is also regulated by the general control.
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Affiliation(s)
- H A Mountain
- Department of Microbiology, University of Umeå, Sweden
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Johnson RR, Powers LV, Failor BH, Gabl EF, Shepard CL, Busch GE, Hammerling P, Larsen JT, Rockett PD, Schroeder RJ, Sullivan D. Low-preheat cryogenic implosion experiments with a shaped 0.53- microm laser pulse. Phys Rev A 1990; 41:1058-1070. [PMID: 9903188 DOI: 10.1103/physreva.41.1058] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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