ABSTRACT
Several studies have reported a high prevalence of missed and delayed mild cognitive impairment (MCI) or mild dementia diagnosis, which could lead to delayed treatment and increased patient and caregiver burden. OBJECTIVES: This study aimed to develop a new questionnaire for nonprofessionals to help detect early signs of MCI and dementia. Respondents included patients, family caregivers, or health professionals. Scores are calculated based on the respondent type and age of subject. METHODS: This study consisted of four steps and included 461 respondents. Steps 1-3 were conducted by a working group, and step 4, by 67 specialist members of the Japanese Society of Geriatric Psychiatry. A scoring algorithm was created and predictive diagnostic probability was analyzed using misdiscrimination rate and cross-validation after item selection to establish a cut-off value for MCI or dementia symptoms. Alzheimer's disease, Lewy body dementia, and frontotemporal dementia were diagnosed. RESULTS: The prediction error rate for patient or informant respondents was confirmed from the evaluation results of 13 items. Sensitivity and specificity were 90.6% and 56.6%, respectively, with a cut-off score of 2. Overall, 82% (61 pairs) of respondents received a definitive diagnosis following a diagnosis from the questionnaire. CONCLUSIONS: This questionnaire could promote earlier presentation to clinical settings for treatment. The high sensitivity indicates the utility of this instrument, but it is not meant as a definitive diagnostic tool and should be followed with a professional assessment.
Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Dementia , Aged , Alzheimer Disease/diagnosis , Alzheimer Disease/psychology , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/psychology , Dementia/diagnosis , Dementia/psychology , Humans , Self Report , Surveys and QuestionnairesABSTRACT
An asymptomatic 67-year-old woman was found to have renal tumors by chance on a screening abdominal ultrasound examination. Although surgical resection was planned for both a diagnostic purposes and treatment, she suddenly developed hemorrhage from the cerebral metastasis in the left thalamus, and the surgical procedure was postponed. Irradiation with a gamma knife was performed to treat the cerebral metastasis; however, the patient's general condition quickly worsened, and she died six months after diagnosis. An autopsy showed typical spindle cells in the primary lesion with multiple metastases. Renal spindle cell carcinoma is a relatively rare type of the renal carcinoma that is both very aggressive and exhibits a poor prognosis, with few established treatments. Hence, obtaining an early diagnosis on abdominal ultrasound is important in such cases.
Subject(s)
Brain Neoplasms/secondary , Carcinoma, Renal Cell/secondary , Cerebral Hemorrhage/etiology , Kidney Neoplasms/pathology , Aged , Fatal Outcome , Female , Humans , Magnetic Resonance Imaging , Multimodal Imaging , Tomography, X-Ray ComputedABSTRACT
AIMS: We established automated assay kits for quantifying small dense low-density lipoprotein (sdLDL)-cholesterol (C), LDL-triglyceride (TG), and high-density lipoprotein (HDL)3-C, and apolipoprotein (apo)E-rich HDL-C, and these have been recognized as sensitive biomarkers for predicting coronary artery disease. We investigated the circadian rhythms of these novel lipids to determine if fasting is required to determine basal levels. METHODS: Forty-eight inpatients with type 2 diabetes and 19 healthy volunteers were studied. Blood samples were collected at seven time points, which were obtained after an overnight fast, before and 2 h after each meal, and before the next breakfast. sdLDL-C, LDL-TG, remnant-like particle (RLP)-C, TG-rich lipoprotein (TRL-C), HDL3-C, and apoE-rich HDL-C were measured by the homogeneous methods. NonHDL-C, large buoyant (lb)LDL-C and HDL2-C were calculated by subtracting sdLDL-C from LDL-C or HDL3-C from HDL-C, respectively. RESULTS: Serum TG levels were significantly increased after meals in both healthy participants and patients with diabetes. RLP-C and TRL-C were also increased postprandially. LDL-TG, LDL-C, nonHDL-C, HDL2,3-C, and apoE-rich HDL-C did not exhibit significant fluctuation during the day in healthy participants and patients with diabetes. sdLDL-C was slightly increased postprandially in subjects with diabetes (1-2 mg/dl, 3%-9%), though its increase was not significant compared to the baseline (fasting) level. Significant postprandial reduction was observed with LDL-C and lbLDL-C. There was no influence of statin therapy or oral anti-diabetes drugs on the circadian rhythm of LDL-C subspecies. CONCLUSIONS: Subtle postprandial increase in sdLDL-C is considered a negligible level in general clinical practice. Fasting is not mandatory to measure basal concentrations of LDL and HDL subspecies.
Subject(s)
Diabetes Mellitus, Type 2 , Humans , Cholesterol, LDL , Cholesterol, HDL , Healthy Volunteers , Triglycerides , Lipoproteins, HDL , Apolipoproteins E , Circadian RhythmABSTRACT
Sarcopenia is a geriatric syndrome characterized by decreased physical performance, muscle mass, and strength. Since the intake of 5-aminolevulinic acid (ALA) with iron can increase muscle mass and mitochondria in mice and elevate physical exercise performance in humans, the beneficial effects of ALA in patients with sarcopenia are expected, but this remains unexplored in the literature. This study aimed to assess the efficacy and dose dependency of ALA combined with iron in sarcopenia by measuring skeletal muscle mass index (SMI). Subjects with sarcopenia were enrolled and randomized into the ALA and sodium ferrous citrate (SFC) intake groups (ALA50/SFC29, ALA100/SFC29, ALA150/SFC29, ALA 100/SFC57, and ALA0/SFC29 placebo) and ingested the assigned study food for 12 weeks. The primary endpoint, the change in SMI from baseline to week 12, did not differ significantly between the groups. Hand grip significantly increased or tended to increase from baseline after 12 weeks with all doses of ALA or SFC compared with the placebo group. No consistent changes were observed in the other endpoints, including calf circumference, physical function, or quality of life (QOL). Although this study suggests safe administration and the possibility of ALA improving hand grip strength in patients with sarcopenia, further investigation is required.
Subject(s)
Sarcopenia , Humans , Animals , Mice , Aged , Sarcopenia/drug therapy , Aminolevulinic Acid/adverse effects , Quality of Life , Hand Strength , Iron , Muscle, Skeletal/physiology , Muscle StrengthABSTRACT
BACKGROUND AND PURPOSE: Jumping to conclusion (JTC)-a cognitive bias in thinking processes-leads to drawing conclusions based on little information, and could be related to psychosis and paranoia. While it has recently been pointed out that it could accompany the autism spectrum disorder (ASD), no interventions targeting this bias in adolescents with ASD have been reported. Therefore, this exploratory study investigated the effects of a group social cognition program on JTC bias in adolescents with ASD. PATIENTS AND METHODS: Group rehabilitation using social cognition and interaction training (SCIT) was conducted for 12- to 18-year-old adolescents with ASD. An SCIT program comprehensively targets social cognitive functions, including interventions for JTC bias, and examines changes before and after the SCIT intervention, social cognitive functioning tasks, and subjective quality of life (QOL). RESULTS: Thirteen adolescents with ASD participated in this program ; 10 (76.9%) stayed through it. The proportion of participants with JTC bias decreased significantly before and after SCIT (before : 7/10 ; after : 1/10 ; p = 0.041), and subjective QOL increased significantly (p=0.014). CONCLUSION: The results show that a group social cognition program with a JTC bias approach improves the JTC bias and increases subjective QOL in adolescents with ASD. J. Med. Invest. 70 : 115-122, February, 2023.
Subject(s)
Autism Spectrum Disorder , Psychotherapy, Group , Humans , Adolescent , Child , Quality of Life , Autism Spectrum Disorder/therapy , CognitionABSTRACT
In mammals, the circadian clock consists of transcriptional and translational feedback loops through DNA cis-elements such as E-box and RRE. The E-box-mediated core feedback loop is interlocked with the RRE-mediated feedback loop, but biological significance of the RRE-mediated loop has been elusive. In this study, we established mutant cells and mice deficient for rhythmic transcription of Bmal1 gene by deleting its upstream RRE elements and hence disrupted the RRE-mediated feedback loop. We observed apparently normal circadian rhythms in the mutant cells and mice, but a combination of mathematical modeling and experiments revealed that the circadian period and amplitude of the mutants were more susceptible to disturbance of CRY1 protein rhythm. Our findings demonstrate that the RRE-mediated feedback regulation of Bmal1 underpins the E-box-mediated rhythm in cooperation with CRY1-dependent posttranslational regulation of BMAL1 protein, thereby conferring the perturbation-resistant oscillation and chronologically-organized output of the circadian clock.
Subject(s)
ARNTL Transcription Factors , Circadian Clocks , ARNTL Transcription Factors/genetics , ARNTL Transcription Factors/metabolism , Animals , CLOCK Proteins/genetics , CLOCK Proteins/metabolism , Circadian Clocks/genetics , Circadian Rhythm/genetics , Cryptochromes/genetics , Cryptochromes/metabolism , Mammals/genetics , Mice , Transcription, GeneticABSTRACT
OBJECTIVE: To examine the direct effect of apolipoprotein CIII (apoCIII) on adipokine expressions that are involved in obesity, insulin resistance, or metabolic syndrome. METHODS AND RESULTS: ApoCIII in triglyceride-rich lipoproteins is elevated in patients with obesity, insulin resistance, or metabolic syndrome. Its level is also associated with proinflammatory adipokines. Fully differentiated mouse 3T3L1 adipocytes were incubated with apoCIII. ApoCIII activated nuclear factor κB of 3T3L1 adipocytes and induced the expression of monocyte chemoattractant protein (MCP) 1 and interleukin (IL) 6. ApoCIII also activated extracellular signal-regulated kinase and p38. Mitogen-activated protein kinase kinase (MEK)-1 inhibitor PD98059, but not p38 inhibitor SB203580, inhibited apoCIII-induced upregulation of MCP-1 and IL-6. Previously, it was shown that apoCIII activates proinflammatory signals through toll-like receptor (TLR) 2. TLR2-blocking antibody abolished activation of nuclear factor κB and extracellular signal-regulated kinase induced by apoCIII and inhibited apoCIII-induced upregulation of MCP-1 and IL-6. ApoCIII also reduced adiponectin expression of 3T3L1 adipocytes, which was recovered by TLR2-blocking antibody. ApoCIII induced the expression of MCP-1 and IL-6 in TLR2-overexpressed human embryonic kidney 293 cells but not wild-type human embryonic kidney 293 cells without TLR2. ApoCIII induced the expression of MCP-1 and IL-6 and decreased adiponectin expression in white adipose tissue of wild-type mice but not of TLR2-deficient mice in vivo. CONCLUSIONS: ApoCIII may activate extracellular signal-regulated kinase and nuclear factor kB through TLR2 and induce proinflammatory adipokine expression in vitro and in vivo. Thus, apoCIII links dyslipidemia to inflammation in adipocytes, which, in turn, may contribute to atherosclerosis.
Subject(s)
Adipocytes/metabolism , Apolipoprotein C-III/pharmacology , Chemokine CCL2/metabolism , Interleukin-6/metabolism , Lipoproteins, VLDL/pharmacology , Toll-Like Receptor 2/metabolism , Adipocytes/drug effects , Animals , Cells, Cultured , Humans , Male , Mice , NF-kappa B/metabolismABSTRACT
Prolonged expression of the CRISPR-Cas9 nuclease and gRNA from viral vectors may cause off-target mutagenesis and immunogenicity. Thus, a transient delivery system is needed for therapeutic genome editing applications. Here, we develop an extracellular nanovesicle-based ribonucleoprotein delivery system named NanoMEDIC by utilizing two distinct homing mechanisms. Chemical induced dimerization recruits Cas9 protein into extracellular nanovesicles, and then a viral RNA packaging signal and two self-cleaving riboswitches tether and release sgRNA into nanovesicles. We demonstrate efficient genome editing in various hard-to-transfect cell types, including human induced pluripotent stem (iPS) cells, neurons, and myoblasts. NanoMEDIC also achieves over 90% exon skipping efficiencies in skeletal muscle cells derived from Duchenne muscular dystrophy (DMD) patient iPS cells. Finally, single intramuscular injection of NanoMEDIC induces permanent genomic exon skipping in a luciferase reporter mouse and in mdx mice, indicating its utility for in vivo genome editing therapy of DMD and beyond.
Subject(s)
CRISPR-Associated Protein 9/genetics , CRISPR-Cas Systems , Exons/genetics , Extracellular Vesicles/metabolism , Nanoparticles/chemistry , RNA, Guide, Kinetoplastida/metabolism , Base Sequence , Cell Survival , Dimerization , Gene Editing , Genetic Vectors/metabolism , HEK293 Cells , HIV Protease/metabolism , Humans , Induced Pluripotent Stem Cells/metabolism , Ligands , Luciferases/metabolism , RNA Splicing/genetics , RNA, Catalytic/metabolism , Ribonucleoproteins/metabolism , Tissue Donors , tat Gene Products, Human Immunodeficiency Virus/metabolismABSTRACT
AIM: To examine the association between depressive symptoms and plasma amino acid related metaboli in older adults. METHODS: A total of 152 older adults aged ≥65 years, residing in Niigata, Japan, were used for analysis. We evaluated depressive symptoms using the Geriatric Depression Scale-15, which has been validated in older community-dwelling individuals, and used a cut off score of ≥5 to classify participants as having depressive symptoms. We used high-performance liquid chromatography-electrospray ionization mass spectrometry to measure the concentrations of plasma amino acid-related metabolites, and carried out logistic regression analysis to assess the association between depressive symptoms and plasma amino acid-related metabolites. RESULTS: Of the 119 older adults (mean age 76.3 years) included in the analysis, 22 were classified as having depressive symptoms (depressive group). There were no significant differences in physical and cognitive impairments between participants in the depressive and non-depressive groups. The plasma α-aminobutyric acid (AABA) level was significantly lower in the depressive group than in the non-depressive group (P < 0.001). Logistic regression analysis showed the best-fit model, which included AABA, leucine, threonine, hydroxyl proline and histidine levels (area under the receiver operating characteristic curve 0.8346; 95% confidence interval 0.7365-0.9326). In particular, the plasma AABA level was strongly associated with depressive symptoms. CONCLUSIONS: Plasma AABA level is significantly associated with depression symptoms in older community-dwelling adults in Japan. Thus, plasma AABA might serve as a potential marker of depression in older adults aged ≥65 years. Geriatr Gerontol Int 2019; 19: 254-258.
Subject(s)
Aminobutyrates/blood , Depression/blood , Independent Living , Aged , Aged, 80 and over , Cross-Sectional Studies , Depression/diagnosis , Female , Geriatric Assessment , Humans , Japan , Logistic Models , MaleABSTRACT
AIM: Pneumonia is one of the major causes of mortality in older adults. As the average lifespan has extended and new modalities to prevent or treat pneumonia are developed, the factors that affect the length of hospital stay (LHS) and in-hospital mortality of older patients with pneumonia have changed. The object of the present study was to determine the factors associated with LHS and mortality as a result of pneumonia among older patients with dementia. METHODS: With a retrospective cohort study design, we used the data derived from the Japanese Administrative Database and diagnosis procedure combination/per diem payment system (DPC/PDPS) database. There were 39 336 admissions of older patients for pneumonia between August 2010 and March 2012. Patients with incomplete data were excluded, leaving 25 602 patients for analysis. RESULTS: Having dementia decreased mortality (OR 0.71, P < 0.001) and increased LHS. Multiple logistic regression analysis identified donepezil as an independent factor that decreased mortality in patients with dementia (OR 0.36, P < 0.001). Donepezil was prescribed for 28.7% of these patients, and their mortality rate was significantly lower than those of patients with dementia who were not treated with donepezil and of patients without dementia. The mortality rate was higher for patients with dementia who were not treated with donepezil compared with patients who did not have dementia. All other factors that influenced LHS and mortality were similar to those reported by others. CONCLUSIONS: Donepezil seems to decrease in-hospital mortality as a result of pneumonia among older patients with dementia. Geriatr Gerontol Int 2018; 18: 269-275.
Subject(s)
Dementia/epidemiology , Donepezil/therapeutic use , Hospital Mortality/trends , Pneumonia/drug therapy , Aged , Humans , Retrospective StudiesABSTRACT
OBJECTIVES: As the population ages, the number of lumbar spinal surgeries performed on sarcopenic patients will increase. The purpose of this study was to investigate the prevalence of sarcopenia and evaluated its impact on the results of lumbar spinal surgery. METHODS: This study included 2 groups: One group consisted of patients who underwent whole-body dual-energy X-ray absorptiometry (DXA) scanning before the option of undergoing surgery for lumbar spinal disease (LSD group) and a second group consisted of patients underwent DXA scanning for osteoporosis screening under hospital watch at the geriatric medicine department (control group). In order to evaluate the impact of sarcopenia on the clinical outcome of lumbar spinal surgery, the Japanese Orthopedic Association (JOA) score, the recovery rate based on the JOA score, and visual analogue scale (VAS) scores for lower back pain, lower extremity pain, and lower extremity numbness were compared within the LSD group. RESULTS: The prevalence of sarcopenia showed no statistical difference between groups (control group, 50.7%; LSD group, 46.5%). In the LSD group, while the changes in VAS scores showed no statistical difference between the nonsarcopenia subgroup and sarcopenia subgroup, the sarcopenia subgroup demonstrated inferior JOA scores and recovery rates at the final follow-up when compared with the nonsarcopenia subgroup (Pâ¯<â¯0.05). CONCLUSIONS: This study demonstrated a high prevalence of sarcopenia among the elderly populations in Japan and a negative impact of sarcopenia on clinical outcomes after lumbar spinal surgery.
ABSTRACT
We determined the growth-active domains of milk-growth factor (MGF), human alpha-lactalbumin (HMLA) and human lysozyme (HMLZ), and their sequences. Fetal calf serum (FCS) showed inhibitors against proteases. The growth-stimulation of IMR90 cells in CG medium (free-serum) without FCS was induced in a dose-dependent manner up to 400 ng/ml of HMLA, HMLZ or chicken lysozyme (ChLZ), and also in a time-dependent manner until 48 h but was induced gradually until 1000 ng/ml of bovine alpha-lactalbumin (BVLA). The HMLAL6-peptide (HMLAL6), a cleaved product from HMLA by Endpeptidase Lys C, was growth-stimulative. The sequence of HMLAL6 was matched to 35 amino-acid residues (from No. 59 to No. 93 of HMLA), owing to the sequences of HMLAL6R3, HMLAL6R5 and HMLAL6R7 after the reduction of HMLAL6. The sequences of the reduced peptides from MGFL7-peptide (MGFL7: a cleaved product from MGF by Endpeptidase lysine C matched to those of the peptides from HMLAL6, and were similarly identified as the partial sequence of HMLA (59-93, H(2)N-L.W.C.?.K./S.S.Q.V.P.Q.S.R.N.I.?.D.I.S.?.D.K./F.L. D.D.D.I.T.D.D.I.M.?.A.-COOH). The sequence of HMLZ is similar to that of HMLA. HMLZT7-peptide (HMLZT7), a cleaved product of HMLZ by trypsin, was confirmed to have growth-stimulating activity and it's sequence was partially identified as Y. W.?.N.D.G.K.T.P.G.A.V.N.A.?.H.L. -, owing to the results of HMLZT7R1 (reduction of HMLZT7) and HMLZA7R2 (reduction of HMLZA7-peptide (HMLZA7) cleaved product of HMLZ by Endpeptidase Arg C) and is accordingly the sequence from No. 63 to No. 97 of HMLZ. Therefore, the peptides produced from LA and LZ by proteolysis may play a role of growth-stimulation.
Subject(s)
Growth/drug effects , Lactalbumin/chemistry , Lactalbumin/pharmacology , Muramidase/chemistry , Muramidase/pharmacology , Peptides/chemistry , Peptides/pharmacology , Transforming Growth Factor beta/chemistry , Transforming Growth Factor beta/pharmacology , Alkylation , Amino Acid Sequence , Cell Line , Cell Proliferation/drug effects , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Humans , Molecular Sequence Data , Peptide Hydrolases/chemistry , Serum Albumin, Bovine/chemistryABSTRACT
PURPOSE: To elucidate factors associated with delayed discharge of elderly patients from university hospitals in Japan. METHODS: Questionnaires were sent to all 125 Japanese university hospitals during the period from January, 18 through March, 25, 2004. Thirty-four possible reasons for the delayed discharge were analyzed. RESULTS: Family issues were the most common reason for delayed discharge nationwide. Medical treatment was a factor in delayed discharge in metropolitan areas where university hospitals were under pressure to reduce the mean hospital stay. The lack of chronic beds was identified as a factor associated with delayed discharge. However, the low quality of care at institutes in rural areas may possibly cause delayed discharge, despite adequate number of chronic beds. CONCLUSIONS: Despite the Japanese government encouraging the care of elderly people at home, the present study shows that the leading cause of delayed discharge is that families cannot accept elderly patients directly from university hospitals. Even if the number of chronic beds were to increase, the quality of care provided would not be adequate to allow a smooth transition of elderly patients from university hospitals to such chronic beds in some areas.
Subject(s)
Hospitals, University , Patient Discharge , Aged , Hospital Bed Capacity , Humans , Japan , Length of Stay , Surveys and QuestionnairesABSTRACT
BACKGROUND AND PURPOSE: Metabolome analyses have shown that plasma amino acid profiles reflect various pathological conditions, such as cancer and diabetes mellitus. It remains unclear, however, whether plasma amino acid profiles change in patients with sarcopenia. This study therefore aimed to investigate whether sarcopenia-specific changes occur in plasma amino acid profiles. METHODS: A total of 153 community-dwelling and seven institutionalized elderly individuals (56 men, 104 women; mean age, 77.7±7.0 years) were recruited for this cross-sectional analysis. We performed a comprehensive geriatric assessment, which included an evaluation of hand grip strength, gait speed, muscle mass and blood chemistry, including the concentration of 18 amino acids. RESULTS: Twenty-eight of the 160 participants met the criteria for sarcopenia established by the Asian Working Group on Sarcopenia in Older People. Univariate analysis revealed associations between the presence of sarcopenia and a higher plasma concentration of proline and glutamine, lower concentrations of histidine and tryptophan. Multivariable analysis revealed that a higher concentration of proline was the only variable independently associated with sarcopenia. CONCLUSIONS: The plasma concentration of proline may be useful for understanding the underlying pathophysiology of sarcopenia.
Subject(s)
Proline/blood , Rural Population , Sarcopenia/blood , Aged , Female , Humans , Independent Living/statistics & numerical data , Japan , Male , Multivariate Analysis , Rural Population/statistics & numerical dataABSTRACT
Rat heme-binding protein 23 (HBP23)/peroxiredoxin (Prx I) belongs to the 2-Cys peroxiredoxin type I family and exhibits peroxidase activity coupled with reduced thioredoxin (Trx) as an electron donor. We analyzed the dimer-oligomer interconversion of wild-type and mutant HBP23/Prx I by gel filtration and found that the C52S and C173S mutants existed mostly as decamers, whereas the wild type was a mixture of various forms, favoring the decamer at higher protein concentration and lower ionic salt concentration and in the presence of dithiothreitol. The C83S mutant was predominantly dimeric, in agreement with a previous crystallographic analysis (Hirotsu, S., Abe, Y., Okada, K., Nagahara, N., Hori, H., Nishino, T., and Hakoshima, T. (1999) Proc. Natl. Acad. Sci. U. S. A. 96, 12333-12338). X-ray diffraction analysis of the decameric C52S mutant revealed a toroidal structure (diameter, approximately 130A; inside diameter, approximately 55A; thickness, approximately 45A). In contrast to human Prx I, which was recently reported to exist predominantly as the decamer with Cys(83)-Cys(83) disulfide bonds at all dimer-dimer interfaces, rat HBP23/Prx I has a Cys(83)-Cys(83) disulfide bond at only one dimer-dimer interface (S-S separation of approximately 2.1A), whereas the interactions at the other interfaces (mean S-S separation of 3.6A) appear to involve hydrophobic and van der Waals forces. This finding is consistent with gel filtration analyses showing that the protein readily interconverts between dimer and oligomeric forms. The C83S mutant exhibited similar peroxidase activity to the wild type, which is exclusively dimeric, in the Trx/Trx reductase system. At higher concentrations, where the protein was mostly decameric, less efficient attack of reduced Trx was observed in a [(14)C]iodoacetamide incorporation experiment. We suggest that the dimerdecamer interconversion may have a regulatory role.
Subject(s)
Disulfides/chemistry , Mutation , Peroxiredoxins/chemistry , Peroxiredoxins/genetics , Amino Acid Sequence , Animals , Binding Sites , Chromatography, Gel , Crystallography, X-Ray , Dimerization , Liver/metabolism , Models, Biological , Molecular Sequence Data , Molecular Structure , Molecular Weight , Peroxiredoxins/metabolism , Protein Structure, Secondary , Protein Structure, Tertiary , Rats , Recombinant Proteins/chemistry , Recombinant Proteins/metabolismABSTRACT
Rat 3-mercaptopyruvate sulfurtransferase (MST) contains three exposed cysteines as follows: a catalytic site cysteine, Cys(247), in the active site and Cys(154) and Cys(263) on the surface of MST. The corresponding cysteine to Cys(263) is conserved in mammalian MSTs, and Cys(154) is a unique cysteine. MST has monomer-dimer equilibrium with the assistance of oxidants and reductants. The monomer to dimer ratio is maintained at approximately 92:8 in 0.2 m potassium phosphate buffer containing no reductants under air-saturated conditions; the dimer might be symmetrical via an intersubunit disulfide bond between Cys(154) and Cys(154) and between Cys(263) and Cys(263), or asymmetrical via an intersubunit disulfide bond between Cys(154) and Cys(263). Escherichia coli reduced thioredoxin (Trx) cleaved the intersubunit disulfide bond to activate MST to 2.3- and 4.9-fold the levels of activation of dithiothreitol (DTT)-treated and DTT-untreated MST, respectively. Rat Trx also activated MST. On the other hand, reduced glutathione did not affect MST activity. E. coli C35S Trx, in which Cys(35) was replaced with Ser, formed some adducts with MST and activated MST after treatment with DTT. Thus, Cys(32) of E. coli Trx reacted with the redox-active cysteines, Cys(154) and Cys(263), by forming an intersubunit disulfide bond and a sulfenyl Cys(247). A consecutively formed disulfide bond between Trx and MST must be cleaved for the activation. E. coli C32S Trx, however, did not activate MST. Reduced Trx turns on a redox switch for the enzymatic activation of MST, which contributes to the maintenance of cellular redox homeostasis.
Subject(s)
Sulfurtransferases/chemistry , Thioredoxins/chemistry , Amino Acid Sequence , Animals , Binding Sites , Cysteine/chemistry , Disulfides , Dithiothreitol/chemistry , Enzyme Activation , Escherichia coli/metabolism , Molecular Sequence Data , Oxidation-Reduction , Protein Binding , Rats , Sequence Homology, Amino Acid , Sulfurtransferases/metabolismABSTRACT
We present 2 patients with synchronous Ewing sarcoma family of tumors (ESFTs) and fibro-osseous lesion in the independent sites, possibly causing misjudgment in staging. Each patient showed another activity apart from the primary ESFT lesion on gallium and/or thallium scintigraphy at initial presentation. Of note is that such lesions showed no obvious radiologic change even though the primary ESFT lesions were mildly shrunken during chemotherapy. The biopsies confirmed fibrous dysplasia (FD) in the first patient and fibro-osseous lesion, possibly FD in the second patient. As far as we know, concurrent ESFT and FD in independent sites have never been described. However, this unusual combination emphasized the possibility of concurrent FD mimicking metastasis in a patient with malignancy and the view that exploratory biopsy should be performed in a critical case to make staging. Further investigation will be required about whether the co-occurrence of ESFD and FD in our patients is coincidence or genetic linkage.