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1.
Intern Med ; 63(8): 1139-1147, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-37690849

RESUMEN

A hypercalcemic crisis due to primary hyperparathyroidism is a life-threatening condition. We herein report a 71-years-old man with hypercalcemic crisis due to primary hyperparathyroidism with parathyroid adenoma. Generally, hemodialysis or continuous hemodiafiltration using calcium-free or low-calcium dialysate is performed early for hypercalcemic crisis. In this case, continuous hemodialysis with a common calcium concentration dialysate improved the hypercalcemic crisis, and parathyroidectomy was performed. The patient recovered sufficiently. Prediction of hypercalcemia crisis, appropriate introduction and methods of blood purification therapy, and timing decisions for parathyroidectomy are required for therapeutic management of hypercalcemic crisis with parathyroid adenoma.


Asunto(s)
Hipercalcemia , Hiperparatiroidismo Primario , Neoplasias de las Paratiroides , Masculino , Humanos , Anciano , Calcio , Hipercalcemia/etiología , Hipercalcemia/terapia , Neoplasias de las Paratiroides/complicaciones , Neoplasias de las Paratiroides/cirugía , Hiperparatiroidismo Primario/complicaciones , Hiperparatiroidismo Primario/terapia , Soluciones para Diálisis , Calcio de la Dieta , Diálisis Renal
2.
World J Gastroenterol ; 27(12): 1194-1212, 2021 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-33828394

RESUMEN

BACKGROUND: It is a crucial issue for patients with refractory ulcerative colitis (UC), including steroid-dependent and steroid-refractory patients, to achieve and maintain steroid-free remission. However, clinical studies focused on the achievement of steroid-free remission in refractory UC patients are insufficient. Cytapheresis (CAP) is a non-pharmacological extracorporeal therapy that is effective for active UC with fewer adverse effects. This study comprised UC patients treated with CAP and suggested the efficacy of CAP for refractory UC patients. AIM: To clarify the efficacy of CAP in achieving steroid-free remission in refractory UC patients. METHODS: We retrospectively reviewed the collected data from 55 patients with refractory UC treated with CAP. We analyzed the following points: (1) Efficacy of the first course of CAP; (2) Efficacy of the second, third, and fourth courses of CAP in patients who experienced relapses during the observation period; (3) Efficacy of CAP in colonic mucosa; and (4) Long-term efficacy of CAP. Clinical efficacy was evaluated using Lichtiger's clinical activity index or Sutherland index (disease activity index). Mucosal healing was evaluated using Mayo endoscopic subscore. The primary and secondary endpoints were the rate of achievement of steroid-free remission and the rate of sustained steroid-free remission, respectively. Statistical analysis was performed using the paired t-test and chi-squared test. RESULTS: The rates of clinical remission, steroid-free remission, and poor effectiveness after CAP were 69.1%, 45.5%, and 30.9%, respectively. There were no significant differences in rate of steroid-free remission between patients with steroid-dependent and steroid-refractory UC. The mean disease activity index and Lichtiger's clinical activity index scores were significantly decreased after CAP (P < 0.0001). The rates of steroid-free remission after the second, third, and fourth courses of CAP in patients who achieved steroid-free remission after the first course of CAP were 83.3%, 83.3%, and 60%, respectively. Mucosal healing was observed in all patients who achieved steroid-free remission after the first course of CAP. The rates of sustained steroid-free remission were 68.0%, 60.0%, and 56.0% at 12, 24, and 36 mo after the CAP. Nine patients (36%) had maintained steroid-free remission throughout the observation period. CONCLUSION: Our results suggest that CAP effectively induces and maintains steroid-free remission in refractory UC and re-induces steroid-free remission in patients achieving steroid-free remission after the first course of CAP.


Asunto(s)
Colitis Ulcerosa , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/tratamiento farmacológico , Citaféresis , Humanos , Inducción de Remisión , Estudios Retrospectivos , Esteroides/uso terapéutico , Resultado del Tratamiento
3.
No Shinkei Geka ; 44(8): 661-8, 2016 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-27506843

RESUMEN

Cerebral involvement is rare in polyarteritis nodosa(PAN);furthermore, secondary intracranial hemorrhage due to cerebral aneurysm is extremely rare. We describe an unusual case of repeated subarachnoid hemorrhage(SAH)in a 64-year-old woman with a history of PAN. Initially, she developed severe headache(probable first SAH, day 0), and presented at our hospital with second severe headache with disturbed consciousness on day 6. Computed tomography(CT)revealed that SAH was mainly distributed in the right basal cistern and sylvian fissure(second SAH). Three aneurysms were detected using CT angiography on the bilateral internal carotid arteries. An intentionally delayed surgery was planned because of the high risk period of cerebral vasospasm and takotsubo cardiomyopathy. On day 15, she complained of headache and had a convulsion. CT revealed a third SAH in the left sylvian fissure;cerebral angiography revealed enlargement of the left internal carotid-posterior communicating artery(IC-PC)aneurysm. Coil embolization of the aneurysm was performed on day 16, and she was treated using prednisolone(20mg/day)for PAN. However, on day 20, the patient became comatose, and CT revealed a fourth SAH in the right sylvian fissure. Cerebral angiography revealed enlargement of the right IC-PC aneurysm. Clipping of the aneurysm was successfully performed in spite of ventricular dysfunction, and the dose of prednisolone was increased to 40mg/day. After treatment, the ventricular dysfunction gradually resolved. Cerebral aneurysms with PAN are candidates for intervention because of their strong tendency to rupture. In our case, takotsubo cardiomyopathy might have been associated with impairment of the coronary microcirculation due to PAN. We suggest that aggressive immunosuppressive treatment for PAN and curative treatments for cerebral aneurysms should be considered with careful radiological examination and follow-up monitoring.


Asunto(s)
Aneurisma Roto/cirugía , Enfermedades de las Arterias Carótidas/cirugía , Arteria Carótida Interna/cirugía , Poliarteritis Nudosa/complicaciones , Aneurisma Roto/diagnóstico por imagen , Aneurisma Roto/etiología , Enfermedades de las Arterias Carótidas/complicaciones , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Arteria Carótida Interna/diagnóstico por imagen , Angiografía Cerebral , Femenino , Humanos , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
4.
Environ Sci Pollut Res Int ; 23(15): 14997-5002, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27080407

RESUMEN

This study aimed to investigate the biodegrading potential of Arthrobacter sp. MCO, Arthrobacter sp. CSP, and Nocardioides sp. ATD6 in melamine-contaminated upland soil (melamine: approx. 10.5 mg/kg dry weight) after 30 days of incubation. The soil sample used in this study had undergone annual treatment of lime nitrogen, which included melamine; it was aged for more than 10 years in field. When R2A broth was used as the pre-culture medium, Arthrobacter sp. MCO could degrade 55 % of melamine after 30 days of incubation, but the other strains could hardly degrade melamine (approximately 25 %). The addition of trimethylglycine (betaine) in soil as an activation material enhanced the degradation rate of melamine by each strain; more than 50 % of melamine was degraded by all strains after 30 days of incubation. In particular, strain MCO could degrade 72 % of melamine. When the strains were pre-cultured in R2A broth containing melamine, the degradation rate of melamine in soil increased remarkably. The highest (72 %) melamine degradation rate was noted when strain MCO was used with betaine addition.


Asunto(s)
Actinomycetales/metabolismo , Arthrobacter/metabolismo , Medios de Cultivo/metabolismo , Contaminantes del Suelo/metabolismo , Triazinas/metabolismo , Biodegradación Ambiental , Medios de Cultivo/química , Microbiología del Suelo , Contaminantes del Suelo/análisis , Triazinas/análisis
5.
J Pestic Sci ; 41(1): 20-24, 2016 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-30364893

RESUMEN

Biodegradation of cyromazine was investigated in liquid cultures using three melamine-degrading bacteria Arthrobacter sp. MCO, Arthrobacter sp. CSP and Nocardioides sp. ATD6. Experiments were performed aerobically in a mineral medium with glucose as a carbon source and cyromazine as the sole nitrogen source. All three strains of bacteria degraded cyromazine. Cyromazine at 23 mg/L completely disappeared by Arthrobacter sp. MCO within 7 days. The bacterial density of all three strains increased with degradation of the cyromazine. The cyromazine metabolite N-cyclopropylammeline was detected and identified by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). This is the first report on the use of Arthrobacter sp. and Nocardioides sp. for cyromazine degradation and the occurrence of bacterial growth with cyromazine degradation.

6.
World J Microbiol Biotechnol ; 31(5): 785-93, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25752233

RESUMEN

Melamine belongs to the s-triazine family, and industrially used as raw product in many ways all over the world. Melamine has been reported for human harmful effects and detected from some crops, soil and water. To remove melamine from the polluted environment, the efficient melamine-mineralizing microorganisms have been needed. We newly isolated three melamine-degrading bacteria from the same upland soil sample using soil-charcoal perfusion method. These bacteria were classified as Arthrobacter sp. MCO, Arthrobacter sp. CSP and Microbacterium sp. ZEL by 16S rRNA genes sequencing analysis. Both Arthrobacter species completely degraded melamine within 2 days, and consumed melamine as a sole nitrogen source. Both strains also grew in cyanuric acid as sole nitrogen source, and released small quantities of ammonium ions. These strains are the first identified bacteria that can mineralize both melamine and cyanuric acid as sole initial nitrogen source in Arthrobacter sp. Although ammeline and ammelide intermediates were detected, these strains possess none of the known genes encoding melamine degrading enzymes. Since the Arthrobacter strains also degraded melamine in a high pH liquid medium, they present as potential bioremediation agents in melamine-polluted environments.


Asunto(s)
Arthrobacter/aislamiento & purificación , Arthrobacter/metabolismo , Contaminantes Ambientales/metabolismo , Nitrógeno/metabolismo , Microbiología del Suelo , Triazinas/metabolismo , Arthrobacter/clasificación , Arthrobacter/genética , Biotransformación , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
7.
Appl Environ Microbiol ; 80(22): 6954-64, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25192986

RESUMEN

Genetic characterization was performed for 10 group I Clostridium botulinum strains isolated from botulism cases in Japan between 2006 and 2011. Of these, 1 was type A, 2 were type B, and 7 were type A(B) {carrying a silent bont/B [bont/(B)] gene} serotype strains, based on botulinum neurotoxin (BoNT) production. The type A strain harbored the subtype A1 BoNT gene (bont/A1), which is associated with the ha gene cluster. The type B strains carried bont/B5 or bont/B6 subtype genes. The type A(B) strains carried bont/A1 identical to that of type A(B) strain NCTC2916. However, bont/(B) genes in these strains showed single-nucleotide polymorphisms (SNPs) among strains. SNPs at 2 nucleotide positions of bont/(B) enabled classification of the type A(B) strains into 3 groups. Pulsed-field gel electrophoresis (PFGE) and multiple-locus variable-number tandem-repeat analysis (MLVA) also provided consistent separation results. In addition, the type A(B) strains were separated into 2 lineages based on their plasmid profiles. One lineage carried a small plasmid (5.9 kb), and another harbored 21-kb plasmids. To obtain more detailed genetic information about the 10 strains, we sequenced their genomes and compared them with 13 group I C. botulinum genomes in a database using whole-genome SNP analysis. This analysis provided high-resolution strain discrimination and enabled us to generate a refined phylogenetic tree that provides effective traceability of botulism cases, as well as bioterrorism materials. In the phylogenetic tree, the subtype B6 strains, Okayama2011 and Osaka05, were distantly separated from the other strains, indicating genomic divergence of subtype B6 strains among group I strains.


Asunto(s)
Botulismo/microbiología , Clostridium botulinum/genética , Clostridium botulinum/aislamiento & purificación , Clostridium botulinum/clasificación , Electroforesis en Gel de Campo Pulsado , Variación Genética , Genotipo , Humanos , Japón , Repeticiones de Minisatélite , Datos de Secuencia Molecular , Filogenia , Plásmidos/genética , Polimorfismo de Nucleótido Simple
8.
J Pediatr ; 164(4): 931-3, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24461790

RESUMEN

A 7-week-old boy with flaccid paralysis was diagnosed with infant botulism caused by Clostridium botulinum toxin type A. In this case of infant botulism, untreated well-water was identified as a potential source of this infection.


Asunto(s)
Botulismo/etiología , Microbiología del Agua , Pozos de Agua , Humanos , Lactante , Masculino
9.
Open Forum Infect Dis ; 1(2): ofu061, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25734131

RESUMEN

BACKGROUND: Enterohemorrhagic Escherichia coli (EHEC) O157:H7 infection causes severe diseases such as bloody diarrhea and hemolytic uremic syndrome (HUS). Although EHEC O157:H7 strains have exhibited high genetic variability, their abilities to cause human diseases have not been fully examined. METHODS: Clade typing and stx subtyping of EHEC O157:H7 strains, which were isolated in Japan during 1999-2011 from 269 HUS patients and 387 asymptomatic carriers (ACs) and showed distinct pulsed-field gel electrophoresis patterns, were performed to determine relationships between specific lineages and clinical presentation. RESULTS: Clades 6 and 8 strains were more frequently found among the isolates from HUS cases than those from ACs (P = .00062 for clade 6, P < .0001 for clade 8). All clade 6 strains isolated from HUS patients harbored stx2a and/or stx2c, whereas all clade 8 strains harbored either stx2a or stx2a/stx2c. However, clade 7 strains were predominantly found among the AC isolates but less frequently found among the HUS isolates, suggesting a significant association between clade 7 and AC (P < .0001). Logistic regression analysis revealed that 0-9 year old age is a significant predictor of the association between clade 8 and HUS. We also found an intact norV gene, which encodes for a nitric oxide reductase that inhibits Shiga toxin activity under anaerobic condition, in all clades 1-3 isolates but not in clades 4-8 isolates. CONCLUSIONS: Early detection of EHEC O157:H7 strains that belonged to clades 6/8 and harbored specific stx subtypes may be important for defining the risk of disease progression in EHEC-infected 0- to 9-year-old children.

12.
J Biomed Semantics ; 2: 4, 2011 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-21806842

RESUMEN

BACKGROUND: The interaction between biological researchers and the bioinformatics tools they use is still hampered by incomplete interoperability between such tools. To ensure interoperability initiatives are effectively deployed, end-user applications need to be aware of, and support, best practices and standards. Here, we report on an initiative in which software developers and genome biologists came together to explore and raise awareness of these issues: BioHackathon 2009. RESULTS: Developers in attendance came from diverse backgrounds, with experts in Web services, workflow tools, text mining and visualization. Genome biologists provided expertise and exemplar data from the domains of sequence and pathway analysis and glyco-informatics. One goal of the meeting was to evaluate the ability to address real world use cases in these domains using the tools that the developers represented. This resulted in i) a workflow to annotate 100,000 sequences from an invertebrate species; ii) an integrated system for analysis of the transcription factor binding sites (TFBSs) enriched based on differential gene expression data obtained from a microarray experiment; iii) a workflow to enumerate putative physical protein interactions among enzymes in a metabolic pathway using protein structure data; iv) a workflow to analyze glyco-gene-related diseases by searching for human homologs of glyco-genes in other species, such as fruit flies, and retrieving their phenotype-annotated SNPs. CONCLUSIONS: Beyond deriving prototype solutions for each use-case, a second major purpose of the BioHackathon was to highlight areas of insufficiency. We discuss the issues raised by our exploration of the problem/solution space, concluding that there are still problems with the way Web services are modeled and annotated, including: i) the absence of several useful data or analysis functions in the Web service "space"; ii) the lack of documentation of methods; iii) lack of compliance with the SOAP/WSDL specification among and between various programming-language libraries; and iv) incompatibility between various bioinformatics data formats. Although it was still difficult to solve real world problems posed to the developers by the biological researchers in attendance because of these problems, we note the promise of addressing these issues within a semantic framework.

13.
Anal Bioanal Chem ; 393(4): 1367-75, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19066857

RESUMEN

A simple and quick online solid-phase extraction (SPE) coupled to liquid chromatography (LC)/tandem mass spectrometry (MS/MS) for the determination of the five antibiotics (florfenicol, FF; lincomycin, LCM; oxytetracyclin, OTC; tylosin, TS; valnemulin, VLM) in swine wastewater has been developed. After filtration, aliquots (100 microl) of wastewater samples were directly injected to a column-switching LC system. Some matrix interference was removed by washing up SPE column with 0.2% formic acid solution and acetonitrile. Antibiotics eluted from SPE column were separated on analytical column by converting switching valve and were detected by MS/MS. Calibration curves using the method of standard addition had very good correlation coefficients (r > 0.99) in the range of 0.1 to 2 ng/ml. The intra-day precision of the method was less than 12% and the inter-day precision was between 6 to 17%. The detection limits were 0.01-0.1 ng/ml. When this method was applied to wastewater samples in swine facilities, four compounds (LCM, OTC, TS, and VLM) were detected.


Asunto(s)
Antibacterianos/análisis , Cromatografía Líquida de Alta Presión/métodos , Porcinos , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/análisis , Animales , Calibración , Masculino , Reproducibilidad de los Resultados
14.
Clin Rheumatol ; 27 Suppl 1: S33-5, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18219435

RESUMEN

A 63-year-old man presented with chronic headache and bilateral hearing loss. A physical examination showed bilateral conjunctivitis. Circulating anti-Cogan peptide antibodies were detected by dot blot analysis. He was diagnosed as having Cogan's syndrome (CS). Steroid therapy led to dramatic improvement of his symptoms and abnormal laboratory findings. During a tapering course of steroid therapy, he suffered from headache. An ophthalmoscopic examination revealed papillary edema. Magnetic resonance imaging of the brain showed hypertrophic cranial pachymeningitis (HCP). After steroid pulse therapy, HCP was improved. To our knowledge, this is the first case of CS complicated with HCP.


Asunto(s)
Enfermedades Autoinmunes/complicaciones , Cefalea/inmunología , Pérdida Auditiva Bilateral/inmunología , Meningitis/complicaciones , Meningitis/inmunología , Cefalea/complicaciones , Cefalea/etiología , Pérdida Auditiva Bilateral/complicaciones , Pérdida Auditiva Bilateral/etiología , Humanos , Masculino , Persona de Mediana Edad , Síndrome
15.
Clin Rheumatol ; 27(3): 395-7, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17952482

RESUMEN

A 58-year-old woman with rheumatoid arthritis (RA) developed fever, skin eruptions, leukocytopenia, and thrombocytopenia, 3 weeks after treatment with sulfasalazine. A skin biopsy showed hydropic degeneration of keratinocytes and lymphocytic infiltrate. A bone marrow aspiration demonstrated an increased number of macrophages with hemophagocytosis. Although serologic tests for Epstein-Barr virus (EBV) indicated a previous infection, EBV deoxyribonucleic acid was detected in her serum by polymerase chain reaction. Cessation of sulfasalazine and administration of steroids led to dramatic improvement. This case illustrates that the hemophagocytic syndrome associated with reactivation of EBV can occur as part of drug hypersensitivity reactions in RA patients taking sulfasalazine.


Asunto(s)
Antirreumáticos/efectos adversos , Hipersensibilidad a las Drogas/etiología , Infecciones por Virus de Epstein-Barr/complicaciones , Linfohistiocitosis Hemofagocítica/virología , Sulfasalazina/efectos adversos , Latencia del Virus/efectos de los fármacos , Artritis Reumatoide/complicaciones , Artritis Reumatoide/tratamiento farmacológico , Hipersensibilidad a las Drogas/virología , Femenino , Humanos , Linfohistiocitosis Hemofagocítica/etiología , Persona de Mediana Edad , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/tratamiento farmacológico
17.
Ren Fail ; 29(2): 183-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17365934

RESUMEN

BACKGROUND: Anti-neutrophil cytoplasmic antibodies (ANCA) are classified into perinuclear (P)-ANCA and cytoplasmic-ANCA by an indirect immunofluorescence (IIF) test with ethanol-fixed neutrophils. Circulating P-ANCA with specificity for myeloperoxidase (MPO) are frequently found in patients with pauci-immune necrotizing glomerulonephritis. P-ANCA without a specificity for MPO are also found in a minority of patients with this form of glomerulonephritis, but their clinicopathological features remain poorly delineated. METHODS: The clinical data, the renal pathology, and the outcome were compared between 48 patients with MPO-specific P-ANCA-associated glomerulonephritis (MPO-specific group) and five patients with MPO-nonspecific P-ANCA-associated glomerulonephritis (MPO-nonspecific group). In the MPO-nonspecific group, antibodies against bactericidal/permeability-increasing protein were detected in one patient, but the other known antibodies that can produce a P-ANCA pattern on the IIF test were not detected in the remaining patients. All patients in the two groups were treated with steroids with or without cyclophosphamide. RESULTS: There were no remarkable differences in the degree of hematuria and serum levels of C-reactive protein and creatinine between the two groups. In contrast, proteinuria levels and the rate of glomerular crescent formation were higher in the MPO-nonspecific group than in the MPO-specific group. While the patient survival rate was similar between the two groups, the renal survival rate was lower in the MPO-nonspecific group. CONCLUSIONS: This pilot analysis suggests that there are clinicopathological differences between patients with MPO-specific and -nonspecific P-ANCA-associated pauci-immune necrotizing glomerulonephritis. Renal lesions appear to be more active in patients with MPO-nonspecific P-ANCA than in patients with MPO-specific P-ANCA.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/análisis , Enfermedades Renales/patología , Riñón/patología , Peroxidasa , Anciano , Anciano de 80 o más Años , Especificidad de Anticuerpos , Biopsia , Femenino , Humanos , Riñón/enzimología , Riñón/inmunología , Enfermedades Renales/enzimología , Enfermedades Renales/inmunología , Enfermedades Renales/mortalidad , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
19.
Eur J Biochem ; 271(18): 3765-75, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15355353

RESUMEN

In this report, we have focused our attention on identifying intracellular mammalian proteins that bind S100A12 in a Ca2+-dependent manner. Using S100A12 affinity chromatography, we have identified cytosolic NADP+-dependent isocitrate dehydrogenase (IDH), fructose-1,6-bisphosphate aldolase A (aldolase), glyceraldehyde-3-phosphate dehydrogenese (GAPDH), annexin V, S100A9, and S100A12 itself as S100A12-binding proteins. Immunoprecipitation experiments indicated the formation of stable complexes between S100A12 and IDH, aldolase, GAPDH, annexin V and S100A9 in vivo. Surface plasmon resonance analysis showed that the binding to S100A12, of S100A12, S100A9 and annexin V, was strictly Ca2+-dependent, whereas that of GAPDH and IDH was only weakly Ca2+-dependent. To localize the site of S100A12 interaction, we examined the binding of a series of C-terminal truncation mutants to the S100A12-immobilized sensor chip. The results indicated that the S100A12-binding site on S100A12 itself is located at the C-terminus (residues 87-92). However, cross-linking experiments with the truncation mutants indicated that residues 87-92 were not essential for S100A12 dimerization. Thus, the interaction between S100A12 and S100A9 or immobilized S100A12 should not be viewed as a typical S100 homo- or heterodimerization model. Ca2+-dependent affinity chromatography revealed that C-terminal residues 75-92 are not necessary for the interaction of S100A12 with IDH, aldolase, GAPDH and annexin V. To analyze the functional properties of S100A12, we studied its action in protein folding reactions in vitro. The thermal aggregation of IDH or GAPDH was facilitated by S100A12 in the absence of Ca2+, whereas in the presence of Ca2+ the protein suppressed the aggregation of aldolase to less than 50%. These results suggest that S100A12 may have a chaperone/antichaperone-like function which is Ca2+-dependent.


Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Proteínas S100/química , Proteínas S100/metabolismo , Secuencia de Aminoácidos , Animales , Anexina A5/metabolismo , Sitios de Unión , Western Blotting , Señalización del Calcio , Bovinos , Cromatografía de Afinidad , Reactivos de Enlaces Cruzados , Dimerización , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Humanos , Isocitrato Deshidrogenasa/metabolismo , Pulmón/química , Datos de Secuencia Molecular , Mutación , Pruebas de Precipitina , Pliegue de Proteína , Ratas , Proteínas Recombinantes/metabolismo , Proteínas S100/genética , Análisis de Secuencia de Proteína , Homología de Secuencia de Aminoácido , Resonancia por Plasmón de Superficie
20.
J Biol Chem ; 279(6): 4221-33, 2004 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-14638689

RESUMEN

Although calmodulin is known to be a component of the Hsp70/Hsp90 multichaperone complex, the functional role of the protein remains uncertain. In this study, we have identified S100A1, but not calmodulin or other S100 proteins, as a potent molecular chaperone and a new member of the multichaperone complex. Glutathione S-transferase pull-down assays and co-immunoprecipitation experiments indicated the formation of stable complexes between S100A1 and Hsp90, Hsp70, FKBP52, and CyP40 both in vitro and in mammalian cells. S100A1 potently protected citrate synthase, aldolase, glyceraldehyde-3-phosphate dehydrogenase, and rhodanese from heat-induced aggregation and suppressed the aggregation of chemically denatured rhodanese and citrate synthase during the refolding pathway. In addition, S100A1 suppressed the heat-induced inactivation of citrate synthase activity, similar to that for Hsp90 and p23. The chaperone activity of S100A1 was antagonized by calmodulin antagonists, such as fluphenazine and prenylamine, that is, indeed an intrinsic function of the protein. The overexpression of S100A1 in COS-7 cells protected transiently expressed firefly luciferase and Escherichia coli beta-galactosidase from inactivation during heat shock. The results demonstrate a novel physiological function for S100A1 and bring us closer to a comprehensive understanding of the molecular mechanisms of the Hsp70/Hsp90 multichaperone complex.


Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Ciclofilinas , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Chaperonas Moleculares/metabolismo , Secuencia de Aminoácidos , Animales , Encéfalo/metabolismo , Calcio/metabolismo , Proteínas de Unión al Calcio/química , Proteínas de Unión al Calcio/genética , Calmodulina/metabolismo , Proteínas Portadoras/química , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Bovinos , Proteínas HSP70 de Choque Térmico/química , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/química , Proteínas HSP90 de Choque Térmico/genética , Humanos , Técnicas In Vitro , Cinética , Sustancias Macromoleculares , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Datos de Secuencia Molecular , Isomerasa de Peptidilprolil/química , Isomerasa de Peptidilprolil/genética , Isomerasa de Peptidilprolil/metabolismo , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas S100 , Resonancia por Plasmón de Superficie , Proteínas de Unión a Tacrolimus/química , Proteínas de Unión a Tacrolimus/genética , Proteínas de Unión a Tacrolimus/metabolismo
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