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1.
Clin Radiol ; 78(3): e197-e203, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36481111

RESUMEN

AIM: To identify the characteristic diagnostic features of hepatocellular carcinoma (HCC) and focal nodular hyperplasia (FNH) in Fontan-associated liver disease (FALD) patients using dynamic gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI). MATERIALS AND METHODS: Thirty-one FALD patients (mean age, 28.3 ± 7.2 years) with liver nodules who underwent dynamic Gd-EOB-DTPA-enhanced MRI were enrolled prospectively. Twenty-five patients (mean age, 72.8 ± 11.4 years) with hepatitis C virus (HCV)-related HCC constituted the control group. The tumour-to-liver signal intensity (SI) ratio was measured at 30, 60, 100, 180 seconds and 15 minutes, and the SI ratio was compared among FALD-HCC, FALD-FNH, and HCV-HCC. RESULTS: FALD-HCC exhibited weak early enhancement with mild washout in late phases. FALD-FNH exhibited marked early enhancement that continued until the late phases. The SI ratio was significantly lower for FALD-HCC than for FALD-FNH in all phases. The SI ratio was significantly lower for FALD-HCC than for HCV-HCC only at 30 seconds (p<0.05), whereas poorer washout was seen in FALD-HCC than HCV-HCC in other phases. In 15 minutes, FALD-HCC had a significantly lower SI ratio compared to FALD-FNH (p<0.001). CONCLUSIONS: The time course of Gd-EOB-DTPA-enhanced MRI signal intensity in FALD-HCC was different from that in FALD-FNH or HCV-HCC. This imaging finding may be useful adjunctive information to distinguish FALD-HCC from FALD-FNH.


Asunto(s)
Carcinoma Hepatocelular , Hiperplasia Nodular Focal , Hepatitis C , Neoplasias Hepáticas , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Gadolinio , Hiperplasia Nodular Focal/diagnóstico por imagen , Hiperplasia Nodular Focal/patología , Medios de Contraste , Gadolinio DTPA , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos
2.
Int J Clin Pract ; 66(4): 394-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22420498

RESUMEN

OBJECTIVE: Plasma triglyceride (TG) levels were reported to be high in chronic kidney disease (CKD) patients undergoing haemodialysis (HD) treatment. One of the atherogenic causes of hypertriglyceridemia is the increase in TG-rich lipoprotein remnants, which are equivalent to remnant-like particle cholesterol (RLP-C). Here, we compared the plasma levels of TG, a representative indicator of TG-rich lipoproteins and RLP-C, as well as the TG/RLP-C ratio between CKD patients undergoing HD and controls, in an effort to elucidate the atherogenicity of TG-rich lipoproteins in CKD patients on HD. MATERIALS AND METHODS: Plasma lipid and apo(lipo)protein levels and the TG/RLP-C ratio were compared between 49 CKD patients undergoing HD and 627 controls. Blood sampling for lipid and apoprotein analysis was performed in a 12-h fasting state. Controls were divided into four subgroups according to TG level (from highest to lowest). RLP-C and apo(lipo)proteins were measured using the immunoprecipitation method and turbidimetric immunoassay, respectively. In addition, a comparison between HD patients and age-, gender-, and plasma TG level-matched controls was performed. RESULTS: Plasma TG levels were 107 ± 70 (mean ± SD) mg/dl in HD patients and 115 ± 72 mg/dl in controls. Plasma RLP-C levels were 6.7 ± 4.5 mg/dl in HD patients and 4.6 ± 3.5 mg/dl in the controls (p < 0.0001). RLP-C levels decreased in descending order from the highest to the lowest TG group in controls. RLP-C levels were higher in HD patients than in controls with plasma TG levels of < 150 mg/dl (p < 0.0001). TG/RLP-C ratios were 19.0 ± 12.0 in HD patients and 25.9 ± 9.5 in controls (p < 0.0001). This ratio was significantly lower in HD patients than in all four TG subgroups. The comparison between HD patients and age-, gender-, plasma TG-matched controls revealed identical results. CONCLUSION: Plasma RLP-C levels were high, and the TG/RLP-C ratio was low in CKD patients undergoing HD treatment. These findings indicate that total plasma TG-rich lipoprotein levels were not increased, but the distribution of plasma TG-rich lipoproteins were skewed towards remnant fractions in CKD patients undergoing HD treatment; these plasma TG-rich lipoproteins appear to be more atherogenic than those in controls.


Asunto(s)
Hipertrigliceridemia/etiología , Fallo Renal Crónico/sangre , Lipoproteínas/metabolismo , Diálisis Renal , Triglicéridos/metabolismo , Anciano , Apolipoproteínas/metabolismo , Estudios de Casos y Controles , Colesterol/metabolismo , Femenino , Humanos , Hipertrigliceridemia/sangre , Fallo Renal Crónico/terapia , Metabolismo de los Lípidos/fisiología , Masculino , Persona de Mediana Edad
4.
Kyobu Geka ; 57(3): 241-4, 2004 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-15035084

RESUMEN

A 20-year-old male was clinically diagnosed as having a mediastinal non seminomatous germ cell tumor because of the elevation of the serum AFP and a large mass lesion in the anterior mediastinal and right thoracic cavity. After 3 courses of chemotherapy with cisplatin (CDDP) and etoposide (VP-16), the serum level decreased to normal range. But, the mediastinal mass enlarged after chemotherapy due to hemorrhage. The tumor was completely removed with sternotomy and right thoracotomy. Postoperative course was uneventful, and he has been free of recurrence for 2 years.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Mediastino/cirugía , Neoplasias de Células Germinales y Embrionarias/cirugía , Neumonectomía/métodos , Adulto , Bleomicina/administración & dosificación , Cisplatino/administración & dosificación , Etopósido/administración & dosificación , Humanos , Masculino , Neoplasias del Mediastino/tratamiento farmacológico , Neoplasias del Mediastino/patología , Invasividad Neoplásica , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias de Células Germinales y Embrionarias/patología , Terapia Recuperativa , Esternón/cirugía , Toracotomía/métodos , Resultado del Tratamiento
5.
Cytopathology ; 13(1): 46-53, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11985568

RESUMEN

Endometrial cytology is important not only for observing cytological findings, but also for assessing histological architecture. Therefore, we attempted to produce a histological preparation from the sample using an automatic fixation apparatus (ACF 1000) which employs a membrane filter method. After observation of the cytological features, the cover slip was removed and a paraffin-embedded section was prepared. Producing a histological section from a cytological specimen prepared with the ACF 1000 apparatus was more useful and easier than with the techniques described to date. Peelability of the cell was avoided by using a silane-coated membrane filter. Observation of the same cell cluster as that observed in the cytological sample was also facilitated in the histological section by this technique.


Asunto(s)
Endometrio/patología , Técnicas de Preparación Histocitológica/métodos , Biopsia , Femenino , Técnicas de Preparación Histocitológica/instrumentación , Humanos , Manejo de Especímenes/métodos , Fijación del Tejido/instrumentación , Fijación del Tejido/métodos , Ultrafiltración
6.
Kyobu Geka ; 55(1): 85-7, 2002 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-11797413

RESUMEN

A 40-year-old female was admitted because of abnormal chest shadows. Chest CT and pulmonary angiography revealed bilateral multiple arteriovenous fistulas in the right S5a, S5b and left S5, S9. Fistula excision and bilateral partial resection of lung were performed through median sternotomy in one stage. This surgical options allows entire removal of the fistulas as well as preservation of lung function.


Asunto(s)
Fístula Arteriovenosa/cirugía , Arteria Pulmonar , Procedimientos Quirúrgicos Pulmonares/métodos , Venas Pulmonares , Esternón/cirugía , Adulto , Fístula Arteriovenosa/complicaciones , Femenino , Humanos , Arteria Pulmonar/cirugía , Venas Pulmonares/cirugía , Telangiectasia Hemorrágica Hereditaria/complicaciones
7.
Cytopathology ; 12(1): 37-43, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11256935

RESUMEN

We conducted a comparative study of angiogenesis observed in endometrial aspirates according to histological type. Cytological specimens from 14 cases of proliferative phase endometrium, 21 cases of endometrial hyperplasia and 18 cases of well-differentiated endometrial adenocarcinoma were used in the investigation. Immunohistochemical staining was performed according to standard methods using CD34 monoclonal antibody, and new vessels were examined. New vessels were identified in all of the histological types, but no morphological differences were seen. New vessels were observed in more cases of adenocarcinoma than in cases of normal tissue or hyperplasia, and the differences were significant. The difference between the maximum and minimum rates of occurrence of cell clusters possessing new vessels tended to be greater in adenocarcinoma than in the other tissue types (P < 0.05). Based on the above findings, examination of new vessels appearing in aspirated endometrial specimens appeared to be of help in differential diagnosis, but it also seemed necessary to take changes due to the menstrual cycle etc. into consideration.


Asunto(s)
Adenocarcinoma/patología , Hiperplasia Endometrial/patología , Neoplasias Endometriales/patología , Endometrio/irrigación sanguínea , Neovascularización Patológica , Endometrio/patología , Femenino , Humanos
8.
J Cardiol ; 34(1): 35-40, 1999 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-10422624

RESUMEN

A 48-year-old man with hypertrophic obstructive cardiomyopathy was treated by nonsurgical septal ablation. He had previously received medical treatment using atenolol and verapamil, but severe symptoms of chest discomfort, dyspnea, and shortness of breath had persisted for 2 years. Under coronary angiography control, the first major septal branch of the anterior descending coronary artery was catheterized with a 2.0 mm coaxial percutaneous transluminal coronary angioplasty balloon catheter. After inflation of the balloon, 1.5 ml of absolute alcohol was slowly injected into the septal artery to induce a small septal infarction. The left ventricular outflow pressure gradient was decreased from 108 before to 30 mmHg after the procedure as measured by Doppler echocardiography. His chest symptom improved from New York Heart Association class III to II and left ventricular outflow gradient was maintained at 0 mmHg (at rest) at 3 months after treatment. This is a new, less invasive treatment using catheterization instead of surgical myectomy. The indication, complication, and long-term effect of the treatment must be carefully evaluated, but this is expected to become a useful method.


Asunto(s)
Cardiomiopatía Hipertrófica/terapia , Ablación por Catéter/métodos , Etanol/administración & dosificación , Angioplastia Coronaria con Balón , Angiografía Coronaria , Ecocardiografía Doppler , Humanos , Masculino , Persona de Mediana Edad
9.
Panminerva Med ; 41(1): 18-21, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10230251

RESUMEN

BACKGROUND: The aim of this study was to find out whether intravenously administered heparin is distributed equally not only proximal but also distal to the arterial occlusion level in vascular reconstructive surgery. METHODS: Ten consecutive patients (7 men and 3 women) with an average age of 69.9 years (range, 51 to 76 years) who underwent graft replacement for aortic abdominal aneurysm from April to December 1994 were studied. Mean aortic clamp time was 76 minutes. Heparin sodium (100 U/kg) was administered intravenously to keep activated clotting time (ACT) over 250 secs and was neutralized by protamine sulfate (1 mg/kg) just after reperfusion. ACT, blood lactate and CPK-MM in the brachial and dorsal pedis artery were measured before heparin administration (control), just after arterial occlusion, just before reperfusion and 10 minutes after protamine administration. RESULTS: ACT was significantly prolonged after arterial occlusion and recovered after protamine administration with no significant differences between proximal and distal values at each point. Lactate showed significant increase after arterial occlusion which was more remarkable distally. CPK-MM was all the way within the normal range. CONCLUSIONS: In vascular reconstructive surgery which requires temporary arterial occlusion for as long as 80 minutes, the effect of heparin is excellent and equal throughout the body by collateral vessels, and the metabolic influence due to blockade of the blood flow is not so critical as to lead to cellular damage although anaerobic glycolysis is promoted distally due to hypoxia.


Asunto(s)
Anticoagulantes/uso terapéutico , Aneurisma de la Aorta Abdominal/terapia , Heparina/uso terapéutico , Procedimientos de Cirugía Plástica , Procedimientos Quirúrgicos Vasculares , Anciano , Terapia Combinada , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
J Cardiovasc Surg (Torino) ; 39(2): 175-8, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9639001

RESUMEN

In Behçet's disease, an aneurysm is prone to progress rapidly to a pseudoaneurysm. Acute limb ischemia due to acute thrombosis of a femoral pseudoaneurysm and subsequent Horner's syndrome due to another subclavian pseudoaneurysm are very rare but acceptable complications in Behçet's disease. We present a case of Behçet's disease with multiple pseudoaneurysms, which also showed these other clinical manifestations. Over a short time span, the patient rapidly developed left femoral and right subclavian pseudoaneurysms, which were successfully resected with graft replacements.


Asunto(s)
Aneurisma Falso/complicaciones , Síndrome de Behçet/complicaciones , Arteria Femoral , Arteria Subclavia , Adulto , Aneurisma Falso/diagnóstico por imagen , Aneurisma Falso/cirugía , Angiografía de Substracción Digital , Implantación de Prótesis Vascular , Estudios de Seguimiento , Síndrome de Horner/complicaciones , Humanos , Masculino , Trombosis/diagnóstico por imagen , Trombosis/etiología , Trombosis/cirugía , Tomografía Computarizada por Rayos X
11.
J Neurooncol ; 38(1): 41-9, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9540056

RESUMEN

Association of p53 gene abnormalities with tumor progression and prognosis of many neoplasms has been demonstrated, but little is known about the clinical significance of p53 abnormalities in meningiomas. The significance of p53 protein expression in recurrent meningiomas and its relationships with MDM2 protein and proliferation activity were investigated by analyzing 39 meningiomas immunohistochemically. p53 protein was expressed in 11 (35%) of 31 non-recurrent and 7 (88%) of 8 recurrent meningiomas. A high frequency of p53 expression was observed in recurrent meningiomas, which tended to have a high p53 positive index (p53 PI), indicating that p53 immunoreactivity may be a marker for predicting tumor recurrence. Four recurrent meningiomas with high p53 PIs were analyzed by the polymerase chain reaction-single strand conformation polymorphism method to detect p53 gene mutations, but none were found in exons 4-8 of this gene. Fifteen (71%) of 21 MDM2-positive and 3 (17%) of 18 MDM2-negative tumors expressed p53 protein, showing that MDM2 expression was more common in meningiomas with p53 expression. p53 immunoreactivity in the absence of mutation may indicate stabilization of the wild type through interaction with the MDM2 protein. The Ki-67/MIB-1 proliferation index (MIB-1 PI) correlated well with recurrence. The p53-positive tumors had a significantly higher mean MIB-1 PI than p53-negative tumors, suggesting that wild-type p53 inactivation by the MDM2 protein may be involved in controlling the proliferative activity in meningiomas. In conclusion, immunohistochemical examination for p53 protein as well as proliferative activity may help predict the malignant potential of tumor recurrence.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Proteínas de Neoplasias/biosíntesis , Recurrencia Local de Neoplasia/metabolismo , Adulto , Anciano , Antígenos Nucleares , Femenino , Humanos , Antígeno Ki-67/biosíntesis , Masculino , Neoplasias Meníngeas/patología , Meningioma/patología , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Proteínas Nucleares/biosíntesis , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas c-mdm2 , Proteína p53 Supresora de Tumor/biosíntesis
12.
J Biol Chem ; 273(9): 5243-7, 1998 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-9478980

RESUMEN

Each amino acid in the putative transmembrane helix III and its flanking regions (from Gly-62 to Tyr-98) of the Tn10-encoded metal-tetracycline/H+ antiporter (Tet(B)) was individually replaced with Cys. Out of these 37 cysteine-scanning mutants, the mutants from G62C to R70C and from S92C to Y98C showed high or intermediate reactivity with [14C]N-ethylmaleimide (NEM) except for the M64C mutant. On the other hand, the mutants from R71C to S91C showed almost no reactivity with NEM except for the P72C mutant. These results confirm that the transmembrane helix III is composed of 21 residues from Arg-71 to Ser-91. The majority of Cys replacement mutants retained high or moderate tetracycline transport activity. Cys replacements for Gly-62, Asp-66, Ser-77, Gly-80, and Asp-84 resulted in almost inactive Tet(B) (less than 3% of the wild-type activity). The Arg-70 --> Cys mutant retained very low activity due to a mercaptide between Co2+ and a SH group (Someya, Y., and Yamaguchi, A. (1996) Biochemistry 35, 9385-9391). Three of these six important residues (Ser-77, Gly-80, and Asp-84) are located in the transmembrane helix III and one (Arg-70) is located in the flanking region. These four functionally important residues are located on one side of the helical wheel. Only two of the residual 31 Cys mutants were inactivated by NEM (S65C and L97C). Ser-65 and Leu-97 are located on the cytoplasmic and periplasmic loops, respectively, in the topology of Tet(B). The degree of inactivation of these Cys mutants with SH reagents was dependent on the volume of substituents. In the presence of tetracycline, the reactivity of the S65C mutant with NEM was significantly increased, in contrast, the reactivity of L97C was greatly reduced, indicating that the cytoplasmic and periplasmic loop regions undergo substrate-induced conformational change in the mutually opposite direction.


Asunto(s)
Antiportadores/química , Proteínas Bacterianas/química , Estructura Secundaria de Proteína , Tetraciclinas/metabolismo , Secuencia de Aminoácidos , Antiportadores/genética , Antiportadores/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Transporte Biológico , Cisteína/genética , Elementos Transponibles de ADN/genética , Etilmaleimida/metabolismo , Metales/metabolismo , Metilmetanosulfonato/análogos & derivados , Metilmetanosulfonato/farmacología , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Protones , Reactivos de Sulfhidrilo/metabolismo
13.
J Antibiot (Tokyo) ; 51(12): 1081-6, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10048566

RESUMEN

A new antifungal antibiotic, BE-31405, was isolated from the culture broth of a fungal strain, Penicillium minioluteum F31405. BE-31405 was isolated by adsorption on high porous polymer resin (Diaion HP-20), followed by solvent extraction, precipitation and crystallization. BE-31405 showed potent growth inhibitory activity against pathogenic fungal strains such as Candida albicans, Candida glabrata and Cryptococcus neoformans, but did not show cytotoxic activity against mammalian cells such as P388 mouse leukemia. The mechanism studies indicated that BE-31405 inhibited the protein synthesis of C. albicans but not of mammalian cells.


Asunto(s)
Antifúngicos/farmacología , Hidrocarburos Aromáticos con Puentes/farmacología , Penicillium/metabolismo , Animales , Antibióticos Antineoplásicos/farmacología , Antifúngicos/biosíntesis , Antifúngicos/química , Hidrocarburos Aromáticos con Puentes/química , Hidrocarburos Aromáticos con Puentes/metabolismo , Candida/efectos de los fármacos , Candida albicans/efectos de los fármacos , Fenómenos Químicos , Química Física , Cryptococcus neoformans/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Fermentación , Técnicas In Vitro , Indenos , Leucemia P388/tratamiento farmacológico , Espectroscopía de Resonancia Magnética , Ratones , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Inhibidores de la Síntesis de la Proteína/farmacología , Conejos , Reticulocitos/efectos de los fármacos , Reticulocitos/metabolismo , Células Tumorales Cultivadas
14.
Ann Thorac Surg ; 64(2): 394-8, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9262582

RESUMEN

BACKGROUND: There have been sporadic cases of persistent atrial fibrillation and sick sinus syndrome after the maze procedure. The purpose of this study was to identify the predictors of sinus rhythm restoration after operation. METHODS: Between March 1993 and June 1995, we evaluated retrospectively 96 consecutive patients who underwent the maze procedure (maze III) in combination with another type of cardiac operation. Four patients who died and 6 patients who required permanent pacemaker implantation because of sick sinus syndrome were excluded. Ambulatory electrocardiographic monitoring was evaluated 1 year after operation. Multiple logistic regression analysis was applied to identify the predictors of sinus rhythm restoration. RESULTS: The final population comprised 86 patients (mean age, 59.8 years; 67 patients with mitral valve disease). Overall, sinus rhythm was restored in 68 of 86 patients (79.1%). The magnitude of the atrial fibrillatory wave positively predicted postoperative sinus rhythm restoration. Conversely, left atrial diameter was inversely related to postoperative sinus rhythm restoration. The odds ratio of having both a fine atrial fibrillatory wave (< 1.0 mm) and enlarged left atrial diameter (> or = 65 mm) for patients with sinus rhythm restoration was 0.04 (95% confidence interval, 0.01 to 0.28). CONCLUSIONS: Atrial fibrillatory wave and left atrial diameter were independent predictors of sinus rhythm restoration after the maze procedure in patients with chronic atrial fibrillation and organic heart disease.


Asunto(s)
Fibrilación Atrial/cirugía , Procedimientos Quirúrgicos Cardíacos , Adulto , Anciano , Fibrilación Atrial/complicaciones , Fibrilación Atrial/fisiopatología , Cateterismo Cardíaco , Intervalos de Confianza , Ecocardiografía , Electrocardiografía Ambulatoria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Análisis de Regresión , Estudios Retrospectivos , Resultado del Tratamiento
15.
Nihon Kyobu Geka Gakkai Zasshi ; 45(11): 1898-902, 1997 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-9430975

RESUMEN

Aortic arch coarctation proximal to the left subclavian artery is a rare anomaly. It is about 1% of all coarctation of the aorta. This 16 days neonate with coarctation of aortic arch with severe subaortic stenosis and ventricular septal defect was underwent two staged repair. In the first-stage operation, coarctation of the aortic arch was reconstructed by extended end to end direct anastomosis through posterolateral thoracotomy. In the second stage, we performed intracardiac repair with use of a technique which included resection of superior margin of conus septum through VSD and patch closure of VSD. The postoperative pressure study showed no gradient between left ventricle and left radial artery. The postoperative course was satisfactory. This patient is doing well.


Asunto(s)
Coartación Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Defectos del Tabique Interventricular/cirugía , Anastomosis Quirúrgica , Aorta Torácica/cirugía , Procedimientos Quirúrgicos Cardíacos/métodos , Humanos , Recién Nacido , Masculino
16.
FEBS Lett ; 391(3): 243-6, 1996 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-8764982

RESUMEN

Three transmembrane aspartyl residues play essential roles in the transposon Tn10-encoded metal-tetracycline/H+ antiporter (Tet(B)) [Yamaguchi, A. et al. (1992) J. Biol. Chem. 267, 7490-7498]. The tetK gene-encoding tetracycline resistance protein (Tet(K)) of Staphylococcus aureus mediates metal-tetracycline/H+ antiport similarly to Tet(B); however, it has no transmembrane aspartyl residue. On the other hand, Tet(K) has three glutamyl residues, Glu-30, Glu-152 and Glu-397, in the putative transmembrane regions. In the present work, tet(K) gene was expressed in Escherichia coli and the transport activity was measured in everted membrane vesicles. When these glutamyl residues were replaced with Gln, the tetracycline transport activity was almost completely lost, indicating the important roles of these residues in Tet(K). In the case of Glu-397, even the charge-conserved mutation to Asp caused complete loss of the activity. On the other hand, the mutation of Glu-30 and Glu-152 to Asp resulted in significant retention of transport activity. These results are similar to those on the mutation of the three transmembrane aspartyl residues in Tet(B), indicating that the transmembrane glutamyl residues in Tet(K) play roles similar to those of the transmembrane aspartyl residues in Tet(B).


Asunto(s)
Antiportadores/química , Proteínas Bacterianas/química , Ácido Glutámico/metabolismo , Staphylococcus aureus/metabolismo , Secuencia de Aminoácidos , Antiportadores/genética , Ácido Aspártico/metabolismo , Proteínas Bacterianas/genética , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Estructura Secundaria de Proteína , Staphylococcus aureus/genética , Tetraciclina/metabolismo , Resistencia a la Tetraciclina
17.
Acta Neuropathol ; 92(1): 1-7, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8811118

RESUMEN

Nucleolin (110 kDa) is a major nucleolar protein in eukaryotic cells and one of the nucleolar organizer region (NOR)-associated proteins. We studied immunohistochemically 32 cases of meningioma, using specific antisera against nucleolin, and analyzed various nucleolin parameters, such as the number of regions and the total area of nucleolin staining per nucleus. The mean number and area of nucleolin stainings per nucleus were compared with the histological malignancy and Ki-67/MIB-1 proliferation index; the correlation with parameters of silver-stained NOR (AgNOR) was also studied. The results showed that there were statistically significant differences in the mean number and area of nucleolin stainings per nucleus between meningiomas and other two groups, atypical and anaplastic meningiomas (P < 0.05), although there was no difference between atypical and anaplastic meningiomas. The mean number and area of nucleolin stainings per nucleus were correlated with the incidence of Ki-67 positivity and AgNOR area. In view of the technical problems inherent in AgNOR staining, immunohistochemistry for nucleolin may represent a more specific and reproducible means for NOR visualization and be a promising technique for assessing cell proliferation.


Asunto(s)
Neoplasias Meníngeas/química , Neoplasias Meníngeas/patología , Meningioma/química , Meningioma/patología , Proteínas Nucleares/análisis , Fosfoproteínas/análisis , Proteínas de Unión al ARN , Adulto , Anciano , Antígenos Nucleares , Biomarcadores/análisis , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Región Organizadora del Nucléolo/química , Región Organizadora del Nucléolo/patología , Células Tumorales Cultivadas , Nucleolina
18.
Kyobu Geka ; 49(7): 567-9, 1996 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-8753032

RESUMEN

A 40-year-old male underwent operation with a suspected diagnosis of a ruptured of Valsalva aneurysm and a bicuspid aortic valve. The aneurysm with an apical rupture protruded into the membranous septum, between the leaflets of the tricuspid valve. The aortic valve was bicuspid, with the aneurysm originating from the right sinus of Valsalva. We presume that the bicuspid aortic valve tends to cause the sinus of Valsalva aneurysm in point that each coronary sinus is given excessive pressure compared with that in the normal aortic valve. Rarity of the combined cases is possibly because the bicuspid aortic valve is frequent while the sinus of Valsalva aneurysm is rare in Western countries and vice versa in Japan.


Asunto(s)
Aneurisma Roto/cirugía , Aneurisma de la Aorta/cirugía , Válvula Aórtica/anomalías , Seno Aórtico , Adulto , Aneurisma Roto/etiología , Aneurisma de la Aorta/etiología , Femenino , Humanos
19.
Kyobu Geka ; 49(5): 405-7, 1996 May.
Artículo en Japonés | MEDLINE | ID: mdl-8992047

RESUMEN

A 20-year-old man underwent total cavopulmonary shunt for univentricular heart type A (A.L.L.) with hemiazygos connection six years ago. Four years later, his condition deteriorated with easy fatigue and cyanosis. Cardiac catheterization showed recanalization of ligated SVC. Chest CT showed tight adhesion between the chest wall and the ascending aorta. We approached the heart through left anterolateral thoracotomy in order to avoid injury of the aorta and the ventricle during redo median sternotomy. Total cavopulmonary connection with intraatrial conduit was performed under circulatory arrest and retrograde cardioplegia without aortic cross clamp. His postoperative course was satisfactory. Left thoracotomy was useful for total cavopulmonary connection following total cavopulmonary shunt associated with postoperative adhesion.


Asunto(s)
Puente Cardíaco Derecho , Defectos del Tabique Interventricular/cirugía , Adulto , Paro Cardíaco Inducido , Humanos , Masculino , Reoperación , Toracotomía/métodos
20.
J Biol Chem ; 271(7): 3706-13, 1996 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-8631984

RESUMEN

Biosynthesis and intracellular transport of 70-kda peroxisomal membrane protein (pmp70) has been studied in rat hepatoma, h-4-ii-e cells. Pulse-chase analysis showed that a newly synthesized 35S-PMP70 first appeared in the cytosolic fraction and was then transported into the peroxisomal fraction. The half-life of 35S-PMP70 in the cytosolic fraction was approximately 3 min. Integration of 35S-PMP70 into membranes occurred in the peroxisomal fraction and was completed within 30 min. No proteolytic processing of 35S-PMP70 was observed. An in vitro import system was reconstituted to characterize the insertion mechanism of PMP70 into peroxisomes. Peroxisomes isolated from rat liver were incubated at 26 degrees C with [35S]methionine-labeled in vitro translation products of PMP70 mRNA in the presence of the cytosolic fraction. The peroxisomes were reisolated and insertion of 35S-PMP70 into the membrane was analyzed using a Na2CO3 procedure. The binding and insertion of 35S-PMP70 were dependent on temperature and incubation time and was specific for peroxisomes. Pretreatment of peroxisomes with trypsin and chymotrypsin almost abolished the binding and insertion of 35S-PMP70. The translation products contained several truncated 35S-PMP70s. The NH2 terminally truncated 35S-PMP70s, with a molecular mass greater than 50 kDa, bound to and inserted into peroxisomal membranes, whereas truncated 35S-PMP70s smaller than 45 kDa did not. These results suggest that PMP70 is post-translationally transported to peroxisomes without processing and inserted into peroxisomal membranes by a specific mechanism in which a proteinaceous receptor and a certain internal sequence of PMP70 are involved.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Membranas Intracelulares/metabolismo , Hígado/metabolismo , Proteínas de la Membrana/biosíntesis , Microcuerpos/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Fraccionamiento Celular , Línea Celular , Clonación Molecular , Cinética , Neoplasias Hepáticas Experimentales , Proteínas de la Membrana/aislamiento & purificación , Proteínas de la Membrana/metabolismo , Metionina/metabolismo , Mitocondrias Hepáticas/metabolismo , Biosíntesis de Proteínas , Procesamiento Proteico-Postraduccional , Ratas , Radioisótopos de Azufre , Transcripción Genética , Células Tumorales Cultivadas
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