RESUMEN
In Saccharomyces cerevisiae, impairment of protein phosphatase PP2ARts1 leads to temperature and hyperosmotic stress sensitivity, yet the underlying mechanism and the scope of action of the phosphatase in the stress response remain elusive. Using a quantitative mass spectrometry-based approach we have identified a set of putative substrate proteins that show both hyperosmotic stress- and PP2ARts1-dependent changes in their phosphorylation pattern. A comparative analysis with published MS-shotgun data revealed that the phosphorylation status of many of these sites is regulated by the MAPKAP kinase Rck2, suggesting that the phosphatase antagonizes Rck2 signaling. Detailed gel mobility shift assays and protein-protein interaction analysis strongly indicate that Rck2 activity is directly regulated by PP2ARts1 via a SLiM B56-family interaction motif, revealing how PP2ARts1 influences the response to hyperosmotic stress in Yeast.
Asunto(s)
Presión Osmótica , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Monoéster Fosfórico Hidrolasas/metabolismo , Fosforilación , Proteína Fosfatasa 2 , Proteínas Serina-Treonina Quinasas , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transducción de Señal/fisiologíaRESUMEN
AIM: The study aimed to evaluate the incidence of disseminated tumour cells (DTCs) in bone marrow (BM) preoperatively and during follow up and to correlate these with established risk factors in patients with colorectal cancer. METHOD: We prospectively studied BM in 57 patients using the anti-cytokeratin antibody A45-B/B3. RESULTS: The overall detection rate of DTCs was 23% with a similar detection rate through all stages of the disease. No significant association was found between the presence of DTCs and clinicopathological parameters. After a median follow up of 35.4 months, no differences were found in relapse and overall survival between patients with and without DTC preoperatively. In 31 of 45 patients with local disease, we performed a follow-up BM examination after 1 year. In 26% of the patients, the BM status had changed as compared with the preoperative finding. CONCLUSION: This is the first study to report the follow up of DTC in BM in colorectal cancer using the A45-B/B3 antibody. The presence of tumour cells in the preoperative BM had no impact on outcome. The BM status had changed after 12 months in a quarter of patients.
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Médula Ósea/patología , Neoplasias Colorrectales/patología , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales , Médula Ósea/química , Neoplasias Colorrectales/cirugía , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica/métodos , Queratinas/análisis , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Estudios Prospectivos , Estadísticas no Paramétricas , Factores de TiempoRESUMEN
BACKGROUND: Soluble cytokeratin 18 (CK18; M65) and a caspase-cleaved fragment of CK18 (M30) have been used as biomarkers, corresponding to tumor cell death and apoptosis, respectively. METHODS: In the present study, M30 was quantified for the first time in serum samples of colon cancer patients pre- and postoperatively as well as during chemotherapy. Minimal residual disease (MRD) was assessed preoperatively by detection of pan-cytokeratin antibody A45-B/B3-positive cells in bone marrow aspirates. RESULTS: Out of 46 patients, those with colon tumors of stages I and IV had significantly elevated M30 serum concentrations compared to controls (n = 23). In 31 colon cancer patients, M30 determinations were performed prior to and seven days after tumor surgery. A group of 24 patients exhibited a significant decrease of M30 in response to tumor removal, in contrast to seven patients who revealed either persistent or higher M30 levels postoperatively. The frequency of MRD was not significantly different for patients with decreasing (4/24) and persisting (3/7) M30. However, M30 correlated significantly with the increased number of recurrences within 36 months in the group with persisting M30 (4/7 versus 2/24, p = 0.032; hazard ratio 8.3, p = 0.016). In a group of patients (n = 10) receiving capecitabine/oxaliplatin chemotherapy (CapOx), transient increases in M30 did not correlate with responses. CONCLUSION: The data obtained within the present limited pilot study in colon cancer patients demonstrate that perioperative changes of M30 may indicate systemic residual tumor load and increased risk of recurrence warranting further evaluation of this marker of apoptosis in a larger prospective clinical trial.
Asunto(s)
Caspasas/sangre , Neoplasias del Colon/sangre , Queratina-18/sangre , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/sangre , Distribución de Chi-Cuadrado , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Terapia Combinada , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasia Residual , Modelos de Riesgos ProporcionalesRESUMEN
The aim of our study was to further improve the preoperative diagnosis of acute appendicitis in children and adolescents. All diagnostic parameters from the patients' medical history (duration and quality of abdominal pain, stool behaviour), the laboratory (leukocytes, C-reactive protein), the clinic (defense, tenderness on percussion, nausea, vomiting, dry tongue) and repeated ultrasound investigations (visualisation of the appendix, indirect signs of an inflammatory process in the appendix region) were documented prospectively and were re-assessed with regard to their diagnostic value. As an additional parameter, procalcitonin was determined. 1156 patients (593 male/563 female) with a mean age of 9.51 years (+/- 1.2 yrs) (max. 15 yrs/min. 2.3 yrs), referred to the department with acute abdominal pain, were examined. 233 (141 male/92 female; 20.1 %) of these patients with a mean age of 10.47 years (+/- 1.1 yr) had appendicitis. Based on the patients' medical history, laboratory findings, the initial clinical investigation and the initial ultrasound investigation, 173 patients (74.3 % of the later operated 233 children with appendicitis) were diagnosed with certainty. The diagnosis of 60 patients (25.7 %) of this group remained uncertain. These patients received a saline enema (Clysmol, Pharmacia & Upjohn Company) and were subjected to a second clinical and sonographic investigation after approximately four hours of parenteral fluid substitution (Ringer's lactate, Mayrhofer Pharmazeutika Company, 4 ml/kg/h). The other 923 patients (79.83 %) were discharged and were followed up as outpatients in the following days. Based on this stepwise procedure, the percentage of correctly diagnosed appendicitis could be increased to 97.4 %. The measurement of procalcitonin proved to be of no value in the diagnosis of acute appendicitis. It may be concluded that in children with abdominal pain, high diagnostic accuracy can only be achieved by a carefully combined evaluation of all individual diagnostic parameters and repeated investigations.
Asunto(s)
Apendicitis/diagnóstico , Enfermedad Aguda , Adolescente , Algoritmos , Proteína C-Reactiva/análisis , Calcitonina/sangre , Péptido Relacionado con Gen de Calcitonina , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Dimensión del Dolor , Estudios Prospectivos , Precursores de Proteínas/sangreRESUMEN
The detection of disseminated tumor cells in bone marrow and blood is increasingly used for staging and therapeutic decisions in breast cancer and other solid tumors. Molecular biological methods improve the diagnostic accuracy. Limitations of the approach relate to the lack of disease-specific marker genes. The detection of tumor cells in the bone marrow after primary therapy is a negative prognostic parameter in many solid tumours. Axillary lymph node dissection and histopathology remain the standard staging procedure in breast cancer, but nodal negative patients exhibiting tumor cells in the bone marrow have an inferior outcome and may benefit from adjuvant therapy. The immunohistochemical and molecular detection of tumour cells in lymph nodes reduces the number of truly nodal-negative patients considerably. Tumour cells in bone marrow and blood may be used to directly monitor therapeutic responses.
Asunto(s)
Neoplasia Residual/diagnóstico , Neoplasia Residual/terapia , Neoplasias/terapia , Humanos , Neoplasia Residual/genética , Reacción en Cadena de la Polimerasa , PronósticoRESUMEN
Immunocytochemical and molecular biological methods to analyze minimal residual disease (MRD) in colorectal cancer in blood and bone marrow were compared. The concept of a study in the Donauspital will be presented which will permit a comparative judgement of minimal residual disease in blood and bone marrow in patients with colorectal cancer.
Asunto(s)
Médula Ósea/patología , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/patología , Neoplasia Residual/sangre , Neoplasia Residual/patología , Neoplasias Colorrectales/genética , Humanos , Inmunohistoquímica/métodos , Biología Molecular/métodosRESUMEN
OBJECTIVE: To evaluate screening for trisomy 21 in a low-risk population utilizing a combination of nuchal translucency measurement in the first trimester and the triple test in the second trimester. METHODS: This was a retrospective study of 9342 women with singleton pregnancies who booked for delivery in our hospital over a period of 5 years. A nuchal translucency scan was carried out at 10-13 weeks' gestation and for those with a measurement of 3.5 mm or more chorionic villus sampling was performed. All other women were asked to return for the triple test at 16 weeks' gestation. Amniocentesis was offered to women in whom the nuchal translucency was 2.5-3.4 mm, the triple test showed a risk of > or = 1 : 250 and in women aged > or = 35 years. RESULTS: The detection rate using the combined screening method was 95% (18/19) with a screen-positive rate of 7.2%. In comparison, screening by maternal age alone would have identified nine (47%) trisomy 21 pregnancies with a screen-positive rate of 10.7%. CONCLUSION: Our data suggest that the combination of nuchal translucency measurement in the first trimester and the triple test in the second trimester is associated with a very high detection rate of trisomy 21 at a relatively low screen-positive rate.
Asunto(s)
Síndrome de Down/diagnóstico , Tamizaje Masivo/métodos , Cuello/diagnóstico por imagen , Cuello/embriología , Ultrasonografía Prenatal , Adolescente , Adulto , Amniocentesis , Biomarcadores/sangre , Síndrome de Down/diagnóstico por imagen , Femenino , Humanos , Edad Materna , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Embarazo , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Radioinmunoensayo , Estudios Retrospectivos , Medición de RiesgoRESUMEN
Placental size has been an interesting topic of research for many years. The main aim of this study was to investigate the feasibility of measuring the placental volume at the end of the first trimester using three-dimensional (3D) ultrasound and to correlate these volumes to known placental functional indices and to factors affecting the placenta. Women with singleton pregnancies at the end of the first trimester were included into this study. The volume data of the placentae were correlated to the crown-rump length (CRL), placenta-associated plasma protein A (PAPP-A), free beta-human chroangiogonadotropin (f-beta-hCG) and other factors that may affect the placental size or function. A total of 1462 pregnancies could be evaluated. Comparison between CRL and placental volume proved a significant correlation (r=0.43, P< 0.001). Due to the observed proportional growth of CRL and placental volume, a quotient (placental volume/CRL) was calculated for each case. There were no differences between placenta/CRL-quotients in relation to gravidity, parity or smoking. Correlations could be established between the placental volume and PAPP-A and f-beta-hCG (PAPP-A: r=0.28, P< 0.001, f-beta-hCG: r=0.10, P< 0.001). The measurement of the placenta in the first trimester can be performed in a high percentage of cases. The placenta/CRL quotient represents a simple method to compare placentae from different gestational days. The correlation between placental volume and maternal serum screening parameters might provide a chance to refine first trimester Down's syndrome serum screening. Future studies will be needed to evaluate the possible clinical use of first trimester placental volume measurements.
Asunto(s)
Edad Gestacional , Placenta/diagnóstico por imagen , Gonadotropina Coriónica Humana de Subunidad beta/sangre , Largo Cráneo-Cadera , Femenino , Humanos , Paridad , Embarazo , Proteína Plasmática A Asociada al Embarazo/análisis , UltrasonografíaRESUMEN
Binding of different regulatory subunits and methylation of the catalytic (C) subunit carboxy-terminal leucine 309 are two important mechanisms by which protein phosphatase 2A (PP2A) can be regulated. In this study, both genetic and biochemical approaches were used to investigate regulation of regulatory subunit binding by C subunit methylation. Monoclonal antibodies selectively recognizing unmethylated C subunit were used to quantitate the methylation status of wild-type and mutant C subunits. Analysis of 13 C subunit mutants showed that both carboxy-terminal and active site residues are important for maintaining methylation in vivo. Severe impairment of methylation invariably led to a dramatic decrease in Balpha subunit binding but not of striatin, SG2NA, or polyomavirus middle tumor antigen (MT) binding. In fact, most unmethylated C subunit mutants showed enhanced binding to striatin and SG2NA. Certain carboxy-terminal mutations decreased Balpha subunit binding without greatly affecting methylation, indicating that Balpha subunit binding is not required for a high steady-state level of C subunit methylation. Demethylation of PP2A in cell lysates with recombinant PP2A methylesterase greatly decreased the amount of C subunit that could be coimmunoprecipitated via the Balpha subunit but not the amount that could be coimmunoprecipitated with Aalpha subunit or MT. When C subunit methylation levels were greatly reduced in vivo, Balpha subunits were found complexed exclusively to methylated C subunits, whereas striatin and SG2NA in the same cells bound both methylated and unmethylated C subunits. Thus, C subunit methylation is critical for assembly of PP2A heterotrimers containing Balpha subunit but not for formation of heterotrimers containing MT, striatin, or SG2NA. These findings suggest that methylation may be able to selectively regulate the association of certain regulatory subunits with the A/C heterodimer.
Asunto(s)
Fosfoproteínas Fosfatasas/metabolismo , Células 3T3 , Animales , Anticuerpos Monoclonales , Antígenos Transformadores de Poliomavirus/metabolismo , Autoantígenos/metabolismo , Proteínas de Unión a Calmodulina/metabolismo , Dominio Catalítico , Proteínas de la Membrana/metabolismo , Metilación , Ratones , Mutación , Proteínas del Tejido Nervioso/metabolismo , Fosfoproteínas Fosfatasas/genética , Fosfoproteínas Fosfatasas/inmunología , Unión Proteica , Proteína Fosfatasa 2 , Subunidades de ProteínaRESUMEN
Protein phosphatase 2A (PP2A) is an essential eukaryotic serine/threonine phosphatase known to play important roles in cell cycle regulation. Association of different B-type targeting subunits with the heterodimeric core (A/C) enzyme is known to be an important mechanism of regulating PP2A activity, substrate specificity, and localization. However, how the binding of these targeting subunits to the A/C heterodimer might be regulated is unknown. We have used the budding yeast Saccharomyces cerevisiae as a model system to investigate the hypothesis that covalent modification of the C subunit (Pph21p/Pph22p) carboxyl terminus modulates PP2A complex formation. Two approaches were taken. First, S. cerevisiae cells were generated whose survival depended on the expression of different carboxyl-terminal Pph21p mutants. Second, the major S. cerevisiae methyltransferase (Ppm1p) that catalyzes the methylation of the PP2A C subunit carboxyl-terminal leucine was identified, and cells deleted for this methyltransferase were utilized for our studies. Our results demonstrate that binding of the yeast B subunit, Cdc55p, to Pph21p was disrupted by either acidic substitution of potential carboxyl-terminal phosphorylation sites on Pph21p or by deletion of the gene for Ppm1p. Loss of Cdc55p association was accompanied in each case by a large reduction in binding of the yeast A subunit, Tpd3p, to Pph21p. Moreover, decreased Cdc55p and Tpd3p binding invariably resulted in nocodazole sensitivity, a known phenotype of CDC55 or TPD3 deletion. Furthermore, loss of methylation also greatly reduced the association of another yeast B-type subunit, Rts1p. Thus, methylation of Pph21p is important for formation of PP2A trimeric and dimeric complexes, and consequently, for PP2A function. Taken together, our results indicate that methylation and phosphorylation may be mechanisms by which the cell dynamically regulates PP2A complex formation and function.
Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas Fúngicas/metabolismo , Fosfoproteínas Fosfatasas/química , Fosfoproteínas Fosfatasas/metabolismo , Proteínas Represoras/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción , Sustitución de Aminoácidos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Dominio Catalítico , Proteínas de Ciclo Celular/química , Proteínas Fúngicas/química , Cinética , Metilación , Mutagénesis Sitio-Dirigida , Nocodazol/farmacología , Fosfoproteínas Fosfatasas/genética , Proteína Fosfatasa 2 , Subunidades de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Represoras/química , Saccharomyces cerevisiae/genéticaRESUMEN
Prolactin is a suspected promotor of breast cancer cell growth, and it shares pleiotropic immunoregulatory properties. We studied plasma prolactin and its drug-induced modulation in 20 women with breast cancer undergoing high-dose chemotherapy and autologous blood stem-cell transplantation. Plasma prolactin levels were serially assayed before and during conditioning and within and beyond 30 days after transplant. Before transplant, prolactin plasma levels were in the age-adjusted range of normal women. During conditioning and within 30 days after transplant, prolactin levels increased in all patients (p < 0.0001), but remained in the normal range. Antiemetic drugs such as metoclopramide and phenothiazines, known to enhance pituitary prolactin secretion, further elevated prolactin plasma levels (p < 0.00001). Patients remaining in continuous complete remission after transplant (median follow-up, 3 years) disclosed higher prolactin levels compared with those obtaining only partial remission or ensuing early relapse. Prolactin levels are regularly elevated during conditioning and within 30 days after autologous transplantation for breast cancer. Further elevations of prolactin plasma levels are induced by metoclopramide and other antiemetic drugs. Elevated plasma prolactin had no adverse effect on disease-free survival after transplant. We propose to investigate further the upregulation of prolactin after transplant aiming to induce a posttransplant consolidative immune reaction.
Asunto(s)
Neoplasias de la Mama/terapia , Trasplante de Células Madre Hematopoyéticas , Inmunoterapia , Prolactina/sangre , Adulto , Antieméticos/uso terapéutico , Antineoplásicos/uso terapéutico , Intervalos de Confianza , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Metoclopramida/uso terapéutico , Persona de Mediana Edad , Fenotiazinas/uso terapéutico , Prolactina/efectos de los fármacos , Inducción de Remisión , Tasa de Supervivencia , Acondicionamiento Pretrasplante , Trasplante Autólogo , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Interaction between the heterodimeric form of protein phosphatase 2A (PP2A) and polyomavirus middle T antigen (MT) is required for the subsequent assembly of a transformation-competent MT complex. To investigate the role of PP2A catalytic activity in MT complex formation, we undertook a mutational analysis of the PP2A 36-kDa catalytic C subunit. Several residues likely to be involved in the dephosphorylation mechanism were identified and mutated. The resultant catalytically inactive C subunit mutants were then analyzed for their ability to associate with a cellular (B subunit) or a viral (MT) B-type subunit. Strikingly, while all of the inactive mutants were severely impaired in their interaction with B subunit, most of these mutants formed complexes with polyomavirus MT. These findings indicate a potential role for these catalytically important residues in complex formation with cellular B subunit, but not in complex formation with MT. Transformation-competent MT is known to associate with, and modulate the activity of, several cellular proteins, including pp60(c-src) family kinases. To determine whether association of MT with an active PP2A A-C heterodimer is necessary for subsequent association with pp60(c-src), catalytically inactive C subunits were examined for their ability to form complexes containing pp60(c-src) in MT-expressing cells. Two catalytically inactive C subunit mutants that efficiently formed complexes with MT also formed complexes that included an active pp60(c-src) kinase, demonstrating that PP2A activity is not essential in cis in MT complexes for subsequent pp60(c-src) association.
Asunto(s)
Antígenos Transformadores de Poliomavirus/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Proteínas Proto-Oncogénicas pp60(c-src)/metabolismo , Células 3T3 , Secuencia de Aminoácidos , Animales , Catálisis , Dominio Catalítico , Células HeLa , Humanos , Ratones , Datos de Secuencia Molecular , Mutagénesis , Fosfoproteínas Fosfatasas/genética , Proteína Fosfatasa 2RESUMEN
Carboxymethylation of proteins is a highly conserved means of regulation in eukaryotic cells. The protein phosphatase 2A (PP2A) catalytic (C) subunit is reversibly methylated at its carboxyl terminus by specific methyltransferase and methylesterase enzymes which have been purified, but not cloned. Carboxymethylation affects PP2A activity and varies during the cell cycle. Here, we report that substitution of glutamine for either of two putative active site histidines in the PP2A C subunit results in inactivation of PP2A and formation of stable complexes between PP2A and several cellular proteins. One of these cellular proteins, herein named protein phosphatase methylesterase-1 (PME-1), was purified and microsequenced, and its cDNA was cloned. PME-1 is conserved from yeast to human and contains a motif found in lipases having a catalytic triad-activated serine as their active site nucleophile. Bacterially expressed PME-1 demethylated PP2A C subunit in vitro, and okadaic acid, a known inhibitor of the PP2A methylesterase, inhibited this reaction. To our knowledge, PME-1 represents the first mammalian protein methylesterase to be cloned. Several lines of evidence indicate that, although there appears to be a role for C subunit carboxyl-terminal amino acids in PME-1 binding, amino acids other than those at the extreme carboxyl terminus of the C subunit also play an important role in PME-1 binding to a catalytically inactive mutant.
Asunto(s)
Hidrolasas de Éster Carboxílico/metabolismo , Fosfoproteínas Fosfatasas/genética , Fosfoproteínas Fosfatasas/metabolismo , Células 3T3 , Secuencia de Aminoácidos , Animales , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/aislamiento & purificación , Dominio Catalítico , Clonación Molecular , ADN Complementario/química , Inhibidores Enzimáticos/farmacología , Humanos , Ratones , Datos de Secuencia Molecular , Peso Molecular , Mutagénesis Sitio-Dirigida , Ácido Ocadaico/farmacología , Proteína Fosfatasa 2 , Relación Estructura-Actividad , LevadurasRESUMEN
BACKGROUND: The mechanism of atrial natriuretic peptide (ANP) release has been difficult to demonstrate in patient studies because of inaccuracies in measuring atrial volumes using conventional techniques. METHODS: Magnetic resonance imaging was performed in 28 clinically stable patients (New York Heart Association class 3) with chronic heart failure to determine right atrial (RA), left atrial (LA), and ventricular volumes. In addition, right heart catheterization was serially performed and plasma ANP levels (in picograms per milliliter) were drawn from the right atrium. RESULTS: Five patients had to be excluded from data analysis for technical reasons. The remaining 23 patients had the following hemodynamic measurements (mean +/- SD): RA mean pressure 7+/-5 mm Hg, pulmonary artery mean pressure 28+/-10, pulmonary capillary wedge pressure 21+/-8 mm Hg, and cardiac index 2.9+/-1.4 (L/min/m2), respectively. Plasma ANP levels were significantly elevated at 162+/-117 (normal range 20 to 65 pg/ml, p < 0.05), as were LA and RA volumes compared with healthy controls (RA volume 128+/-64 ml vs 82+/-25 ml, p < 0.05; LA volume 157+/-54 ml vs 71+/-24 ml, p < 0.01, respectively). ANP showed a stronger relation with atrial volumes (RA volume, r = 0.91, p = 0.0001; LA volume, r = 0.80, p = 0.001) than with atrial pressures (RA mean pressure, r = 0.45, p = 0.03; pulmonary capillary wedge pressure, r = 0.67, p = 0.001). A subgroup analysis of patients with increased RA or LA volumes (>1 SD of mean of controls) revealed a stronger relation between ANP and RA volumes than between ANP and LA volumes. CONCLUSIONS: These data suggest that increased right heart volume with subsequent increased atrial stretch is the major determinant for ANP release in patients with stable CHF.
Asunto(s)
Factor Natriurético Atrial/biosíntesis , Atrios Cardíacos/anatomía & histología , Insuficiencia Cardíaca/sangre , Adulto , Anciano , Función Atrial , Presión Sanguínea , Cateterismo Cardíaco , Enfermedad Crónica , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Contracción Miocárdica , Estudios Prospectivos , Presión Esfenoidal Pulmonar , Radioinmunoensayo , Ventriculografía con Radionúclidos , Análisis de RegresiónRESUMEN
BACKGROUND: In patients with gynecologic malignancies, a 6 kD polypeptide known as the tumor-associated trypsin inhibitor (TATI) is present in high concentrations, both in the urine and the serum. This study attempts to evaluate the usefulness of pretreatment serum levels of TATI (cutoff level 21 ng ml-1) and CA 125 (cutoff levels 35 U ml-1 and 65 U ml-1) in the prediction of early endometrial cancer. PATIENTS AND METHODS: One hundred twenty-seven patients with stage I and II endometrial carcinomas, 110 healthy women and 258 women with benign pelvic pathologies were evaluated. The data obtained were correlated with the tumor stage and tumor grade. RESULTS: Overall, TATI showed a sensitivity of 31% and a specificity of 81%. The sensitivity and specificity of CA 125 > 35 U ml-1 was 25% and 86%, respectively. When both serum tumor markers were combined the sensitivity increased to 48% (CA 125 > 35 U ml-1), with a specificity of 71%. A correlation with the depth of myometrial infiltration was found for neither of the tumor markers under investigation. In addition, neither TATI nor CA 125 correlated well with tumor grade. The combination of TATI and CA 125 had a high positive predictive value (84%) when no other gynecologic pathologies were present. Furthermore, if TATI and CA 125 levels are within normal ranges and gynecological examination does not show other abnormalities besides vaginal bleeding, endometrial carcinoma appears to be very unlikely. CONCLUSION: We concluded that, while TATI and CA 125 may not be recommended as a screening method for the detection of endometrial cancer, the combination of TATI and CA 125 is a valuable additional tool for further evaluation of women with suspected uterine cancer.
Asunto(s)
Biomarcadores de Tumor/sangre , Antígeno Ca-125/sangre , Neoplasias Endometriales/sangre , Neoplasias Endometriales/diagnóstico , Inhibidor de Tripsina Pancreática de Kazal/sangre , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Endometriales/patología , Neoplasias Endometriales/cirugía , Endometriosis/sangre , Femenino , Enfermedades de los Genitales Femeninos/sangre , Enfermedades de los Genitales Femeninos/diagnóstico , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Radioinmunoensayo , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Prostaglandin E1 or prostacyclin were randomly infused in 18 patients with severe chronic heart failure who did not respond to oral treatment. Maximally tolerated dosages of both agents increased cardiac index; however, only prostacyclin decreased mean arterial pressure and increased plasma norepinephrine significantly. Twelve hours after 50% peak dose reduction, atrial natriuretic peptide levels, right atrial pressure, mean pulmonary artery pressure, and mean arterial pressure continued to decrease with prostaglandin E1, whereas the increase in cardiac index was sustained; in contrast, at 50% prostacyclin dose reduction, cardiac index decreased toward baseline, suggesting that, with reduced dosages for chronic infusions, desired hemodynamic changes seem to be sustained with prostaglandin E1 only.
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Alprostadil/administración & dosificación , Antihipertensivos/administración & dosificación , Epoprostenol/administración & dosificación , Insuficiencia Cardíaca/tratamiento farmacológico , Hemodinámica/efectos de los fármacos , Neurotransmisores/sangre , Vasodilatadores/administración & dosificación , Alprostadil/efectos adversos , Antihipertensivos/efectos adversos , Factor Natriurético Atrial/sangre , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Gasto Cardíaco/efectos de los fármacos , Gasto Cardíaco/fisiología , Relación Dosis-Respuesta a Droga , Endotelina-1 , Endotelinas/sangre , Epoprostenol/efectos adversos , Femenino , Insuficiencia Cardíaca/fisiopatología , Hemodinámica/fisiología , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Precursores de Proteínas/sangre , Presión Esfenoidal Pulmonar/efectos de los fármacos , Presión Esfenoidal Pulmonar/fisiología , Vasodilatadores/efectos adversosRESUMEN
The carboxy terminus of protein phosphatase 2A (PP2A) catalytic subunit is highly conserved. Seven out of the last nine residues, including two potential in vivo phosphorylation sites, threonine 304 and tyrosine 307, are completely invariant in all known PP2As. Mutational analysis of the carboxy terminus in vivo was facilitated by efficient immunoprecipitation of trimeric PP2A holoenzyme via an epitope-tagged catalytic subunit. The results indicate that the catalytic subunit carboxy terminus is important for complex formation with the PP2A 55 kDa regulatory B subunit, but not with polyomavirus oncogene, middle tumor antigen (MT), a viral B-type regulatory subunit. Replacing catalytic subunit threonine 304 or tyrosine 307 with a negatively charged amino acid abolished binding of the B subunit to the dimeric enzyme core and altered substrate specificity. Certain other amino acid substitutions of different size and/or charge also abolished or greatly reduced B subunit binding. Substitution of alanine at position 304 or phenylalanine at position 307 did not dramatically reduce B subunit binding or phosphatase activity in vitro, yet the latter substitutions are not found in naturally occurring PP2As. Thus, the wild-type residues are important for a yet unknown function in vivo. Additionally, deleting the carboxy terminal nine amino acids inhibited binding of the B subunit to the dimeric enzyme core, indicating a requirement for one or more of these amino acids for complex formation. MT interaction with the dimeric PP2A enzyme core was not inhibited by any of these mutations. Finally, unlike B subunit, MT does not activate the phosphatase activity of the PP2A heterodimer towards cdc2-phosphorylated histone H1.
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Fosfoproteínas Fosfatasas/química , Fosfoproteínas Fosfatasas/fisiología , Poliomavirus/inmunología , Células 3T3 , Animales , Antígenos de Neoplasias/metabolismo , Antígenos Virales/metabolismo , Sitios de Unión/fisiología , Ratones , Mutagénesis Sitio-Dirigida , Fosfoproteínas Fosfatasas/genética , Fosforilación , Pruebas de Precipitina , Proteína Fosfatasa 2 , Especificidad por Sustrato , Treonina , TirosinaRESUMEN
BACKGROUND: Prostaglandins of the E type are potent endogenous vasodilators that also interfere with the activity of the sympathetic nervous system. Thus treating patients with end-stage heart failure with prostaglandin E1 (PGE1) infusions seems to accord well with the hypothesis that neurohumoral imbalance rather than hemodynamic derangements should be the priority in the treatment of heart failure. METHODS: We sought to investigate neurohumoral in addition to hemodynamic changes during long-term PGE1 infusion and determined plasma renin activity, atrial natriuretic peptide, norepinephrine, and big endothelin plasma levels in 13 male patients with heart failure whose symptoms remained severe in spite of optimized oral therapy with digitalis, nitrates, furosemide (185 +/- 72 mg/d) and enalapril (33 +/- 3 mg/d). PGE1 infusion rate was started with 2.5 ng/kg/min and stepwise increased to the maximum tolerated dose (26 +/- 4 ng/kg/min), which was halved for continuous infusion through the following 12 hours and further stepwise reduced to an average dose of 8 +/- 1 ng/kg/min. Right heart catheterization was performed for acute hemodynamic studies and after 4 weeks. All patients were discharged with a catheter that was connected to a portable pump for home therapy. RESULTS: Acute effects of PGE1 were reductions in systemic blood pressure, (p < 0.05), right atrial pressure (p < 0.001), pulmonary artery pressure (p < 0.05), pulmonary capillary wedge pressure (p < 0.01), systemic and pulmonary vascular resistance index (both p < 0.01) and an increase in cardiac and stroke volume index (both p < 0.001) without a change in heart rate. After 4 weeks a persistent increase from baseline in cardiac index (from 1.9 +/- 0.1 to 2.5 +/- 0.2 L/min/m2; p < 0.01) and in pulmonary vascular resistance index (from 479 +/- 50 to 331 +/- 29 dynes x sec/cm5 x m2; p < 0.05) was observed. Atrial natriuretic peptide (p < 0.05) decreased, and norepinephrine and big endothelin showed a tendency to a lower level. Concomitantly, New York Heart Association functional class changed (p = 0.0001), with one patient's condition remaining class IV, the conditions of seven patients decreasing to class II, and the conditions of five patients decreasing to class III. CONCLUSION: Thus long-term parenteral home therapy with PGE1 infusions in patients with severe end-stage heart failure elicited beneficial clinical and hemodynamic effects without activating neurohumoral counterregulatory systems.
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Alprostadil/uso terapéutico , Atención Ambulatoria , Insuficiencia Cardíaca/tratamiento farmacológico , Vasodilatadores/uso terapéutico , Cateterismo Cardíaco , Estudios de Factibilidad , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/fisiopatología , Hemodinámica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Neurotransmisores/sangre , Proyectos Piloto , Índice de Severidad de la EnfermedadAsunto(s)
Endotelinas/sangre , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/fisiopatología , Trasplante de Corazón , Hemodinámica , Norepinefrina/sangre , Precursores de Proteínas/sangre , Aldosterona/sangre , Factor Natriurético Atrial/sangre , Biomarcadores/sangre , Cateterismo Cardíaco , Cardiomiopatías/sangre , Cardiomiopatías/fisiopatología , Cardiomiopatía Dilatada/sangre , Cardiomiopatía Dilatada/fisiopatología , Endotelina-1 , Femenino , Insuficiencia Cardíaca/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Renina/sangre , Reproducibilidad de los Resultados , Tasa de SupervivenciaRESUMEN
OBJECTIVE: To show that in patients with endometriosis a 6 kD polypeptide, the tumour-associated trypsin inhibitor (TATI), can occur at elevated concentrations in serum. DESIGN: In a prospective study TATI serum levels were assessed prior to surgery in 368 consecutive patients suffering from benign gynaecological diseases (e.g. pelvic pain, infertility, elective sterilisation, uterine fibroids and pelvic masses) with (n = 71) and without (n = 297) endometriosis, who underwent laparoscopy or laparotomy for diagnosis and/or treatment. RESULTS: The TATI serum levels of patients suffering from endometriosis were significantly different from those in the control group and showed a positive correlation with the stage of endometriosis. The sensitivity of TATI was 0.34 with a specificity of 0.85 for all cases of endometriosis, with an increase of sensitivity (0.67) and slight decrease of specificity (0.82), considering only a group of Stage III/IV patients. Excluding patients with benign ovarian cysts, the specificity of TATI was 0.91 and 0.85, respectively. The combination of TATI and CA125 showed an increase of sensitivity to 0.59 for all cases of endometriosis and 0.89 for patients with Stage III/IV endometriosis. CONCLUSIONS: The sensitivity of TATI as a screening method for endometriosis is too low, but considering its high specificity, TATI in combination with CA125 could provide an additional diagnostic tool in diagnosis and follow up of patients with endometriosis.