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1.
Eur Arch Otorhinolaryngol ; 277(4): 1031-1038, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31993767

RESUMEN

PURPOSE: Our aim was to determine whether perioperatively administered corticosteroid treatment has any beneficial effect on the outcome of stapes surgery, with special regard to the audiological results and early postoperative morbidity. METHODS: 84 CO2 laser stapedotomies performed in our institute between 2013 and 2018 were included in our investigation. All cases underwent preoperative and mid-term postoperative pure-tone audiometric evaluation. Vestibular complications were also evaluated. The cases were subdivided into two groups, 23 patients received perioperative i.v. methylprednisolone treatment ("S") while the other 61 patients ("nS") did not receive any adjuvant pharmacological therapy. The data were analyzed retrospectively using IBM SPSS Statistics. RESULTS: CO2 laser stapedotomy proved to be a successful intervention with a significant improvement in ABG and AC thresholds as well. Long-term BC levels were significantly better compared to preoperative ones in the S group; however, in the nS group, no difference could be shown. Hearing and ABG gain were significantly superior in group S [28.1 dB (SD11.2) vs. 18.1 dB (SD 10.9) and 23.9 dB(SD 9.8) vs. 17.2 dB (SD 9.5), respectively]. CONCLUSION: No significant inner ear damage was detectable in the results of our CO2 laser stapedotomy method; however, the positive effect of corticosteroid treatment could be demonstrated through the postoperative hearing levels. We found no statistical difference in early postoperative morbidity. According to our data, the routine administration of corticosteroids during stapes surgery could be an issue worthy of consideration. The effects of perioperative treatment vs that on the first day after surgery, and topical vs. systemic treatment could be the subject of further investigation in a prospective manner.


Asunto(s)
Glucocorticoides/administración & dosificación , Pérdida Auditiva/cirugía , Terapia por Láser , Metilprednisolona/administración & dosificación , Otosclerosis , Cirugía del Estribo , Adulto , Audiometría de Tonos Puros , Femenino , Pérdida Auditiva/diagnóstico , Pérdida Auditiva/tratamiento farmacológico , Humanos , Infusiones Intravenosas , Láseres de Gas/uso terapéutico , Masculino , Persona de Mediana Edad , Otosclerosis/diagnóstico , Otosclerosis/tratamiento farmacológico , Otosclerosis/cirugía , Atención Perioperativa , Estudios Retrospectivos , Resultado del Tratamiento
2.
Microsc Microanal ; 18(2): 406-20, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22436336

RESUMEN

In this series of articles, a method is presented that performs (semi)quantitative phase analysis for nanocrystalline transmission electron microscope samples from selected area electron diffraction (SAED) patterns. Volume fractions and degree of fiber texture are determined for the nanocrystalline components. The effect of the amorphous component is minimized by empirical background interpolation. First, the two-dimensional SAED pattern is converted into a one-dimensional distribution similar to X-ray diffraction. Volume fractions of the nanocrystalline components are determined by fitting the spectral components, calculated for the previously identified phases with a priori known structures. These Markers are calculated not only for kinematic conditions, but the Blackwell correction is also applied to take into account dynamic effects for medium thicknesses. Peak shapes and experimental parameters (camera length, etc.) are refined during the fitting iterations. Parameter space is explored with the help of the Downhill-SIMPLEX. The method is implemented in a computer program that runs under the Windows operating system. Part I presented the principles, while part II elaborated current implementation. The present part III demonstrates the usage and efficiency of the computer program by numerous examples. The suggested experimental protocol should be of benefit in experiments aimed at phase analysis using electron diffraction methods.

3.
Discrete Math ; 311(13): 1197-1203, 2011 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-21643469

RESUMEN

Various topological indices have been put forward in different studies from bio-chemistry to pure mathematics. Among them the Wiener index, the number of subtrees and the Randic index have received great attention from mathematicians. While studying the extremal problems regarding these indices among trees, one interesting phenomenon is that they share the same extremal tree structures. Much effort was devoted to the study of the correlations between these various indices. In this note we provide a common characteristic (the 'semi-regular' property) of these extremal structures with respect to the above mentioned indices, among trees with a given maximum degree. This observation leads to a more unified approach for characterizing these extremal structures. As an application/example, we illustrate the idea by studying the extremal trees regarding the sum of distances between all pairs of leaves of a tree, a new index, which recently appeared in phylogenetic tree reconstruction and the study of the neighborhood of trees.

4.
Oncogene ; 26(7): 982-92, 2007 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-16909106

RESUMEN

We have previously identified PRIMA-1, a low molecular weight compound that restores the transcriptional transactivation function to mutant p53 and induction of apoptosis. To explore the molecular mechanism for PRIMA-1-induced mutant p53-dependent apoptosis, we examined the intracellular distribution of mutant p53 upon treatment with PRIMA-1(MET) by immunofluorescence staining. We found that PRIMA-1(MET) induced nucleolar translocation of mutant p53 and the promyelocytic leukemia (PML) nuclear body-associated proteins PML, CBP and Hsp70. Levels of Hsp70 were significantly enhanced by PRIMA-1(MET) treatment. PRIMA-Dead, a compound structurally related to PRIMA-1 but unable to induce mutant p53-dependent apoptosis, failed to induce nucleolar translocation of mutant p53. Our results suggest that redistribution of mutant p53 to nucleoli plays a role in PRIMA-1-induced apoptosis.


Asunto(s)
Compuestos Aza/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Nucléolo Celular/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Transporte Activo de Núcleo Celular , Apoptosis/genética , Línea Celular Tumoral , Nucléolo Celular/genética , Metilación de ADN , Humanos , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Proteína de la Leucemia Promielocítica , Factores de Transcripción/genética , Proteína p53 Supresora de Tumor/genética , Proteínas Supresoras de Tumor/genética
5.
Mol Cell Biol ; 18(2): 1084-93, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9448006

RESUMEN

PML is a nuclear protein with growth-suppressive properties originally identified in the context of the PML-retinoic acid receptor alpha (RAR alpha) fusion protein of acute promyelocytic leukemia. PML localizes within distinct nuclear structures, called nuclear bodies, which are disrupted by the expression of PML-RAR alpha. We report that PML colocalizes with the nonphosphorylated fraction of the retinoblastoma protein (pRB) within nuclear bodies and that pRB is delocalized by PML-RAR alpha expression. Both PML and PML-RAR alpha form complexes with the nonphosphorylated form of pRB in vivo, and they interact with the pocket region of pRB. The regions of PML and PML-RAR alpha involved in pRB binding differ; in fact, the B boxes and the C-terminal region of PML, the latter of which is not present in PML-RAR alpha, are essential for the formation of stable complexes with pRB. Functionally, PML abolishes activation of glucocorticoid receptor-regulated transcription by pRB, whereas PML-RAR alpha further increases it. Our results suggest that PML may be part of transcription-regulatory complexes and that the oncogenic potential of the PML-RAR alpha protein may derive from the alteration of PML-regulated transcription.


Asunto(s)
Proteínas de Neoplasias/metabolismo , Proteínas Nucleares , Proteínas de Fusión Oncogénica/metabolismo , Proteína de Retinoblastoma/metabolismo , Factores de Transcripción/metabolismo , División Celular , Humanos , Cuerpos de Inclusión/metabolismo , Sustancias Macromoleculares , Proteínas de Neoplasias/genética , Regiones Promotoras Genéticas , Proteína de la Leucemia Promielocítica , Unión Proteica , Receptores de Glucocorticoides/metabolismo , Factores de Transcripción/genética , Transcripción Genética , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor
6.
Oncogene ; 9(3): 809-18, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8108123

RESUMEN

The expression of the retinoblastoma susceptibility (RB-1) gene was investigated in highly proliferating mouse embryonic stem (ES) cells and in slowly proliferating mouse embryonic fibroblasts. The RB protein was expressed at the same level in these two cell types. Mainly hyperphosphorylated RB was detected in exponentially-growing ES cells. Embryonic fibroblasts and embryonic stem cells were synchronized by colcemid block followed by mitotic shake-off. In embryonic fibroblasts, DNA replication started 10-15 h after exit from mitosis and RB was transiently dephosphorylated during the G1 phase as previously described. In ES cells, DNA replication started 2 h after release from the colcemid block but virtually no hypophosphorylated RB was observed after the release. Instead, there was a dramatic decrease in the total RB protein level between exit from mitosis and entry into S phase. These observations were made by using two different monoclonal antibodies, both in immunoblotting and immunoprecipitation experiments. Absence of hypophosphorylated RB and cell cycle-dependent change in total RB protein level may be relevant to the high proliferation rate and to the tumorigenic nature of mouse embryonic stem cells.


Asunto(s)
Fibroblastos/metabolismo , Proteína de Retinoblastoma/genética , Células Madre/metabolismo , Animales , Western Blotting , Ciclo Celular/genética , Diferenciación Celular , Células Cultivadas , Demecolcina/farmacología , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Técnica del Anticuerpo Fluorescente , Expresión Génica , Ratones , Pruebas de Precipitina , Células Madre/citología , Células Madre/efectos de los fármacos
7.
Oncogene ; 8(12): 3427-31, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8247547

RESUMEN

Using a temperature sensitive p53 construct (ts p53), we have earlier shown that expression of wild-type (wt) p53 triggers apoptosis in a v-myc-induced T-cell lymphoma line that lacks endogenous p53, and in a Burkitt lymphoma line that carries mutant p53. We have suggested that apoptosis is elicited by the contradictory signals emanating from the constitutively activated myc gene and the growth arresting signal of wt p53 (Ramqvist et al., 1993; Wang et al., 1993). Work in other laboratories has shown that constitutive c-myc expression can induce apoptosis when cell proliferation is inhibited due to the lack of growth stimulating factors. Expression of bcl-2 could inhibit apoptosis. In order to test whether p53-induced apoptosis can be prevented by bcl-2, we have introduced a retrovirally driven bcl-2 construct into our v-myc-induced murine T-cell lymphoma line, previously transfected with ts p53. About 90% of the parental ts p53 transfected cells died of apoptosis within 3 days after induction of wt p53 expression at 32 degrees C. Two clones of ts p53/bcl-2 double transfectants that expressed high levels of bcl-2 from the introduced construct were completely protected from apoptosis, following transfer of the cells to 32 degrees C. One clone that expressed the exogenous bcl-2 only at a low level was partially protected from wt p53-induced apoptosis. Clones of the parental ts p53 carrying cells transfected with the puromycin resistance gene vector, without the bcl-2 gene underwent 90% apoptosis. These results suggest that bcl-2 may prevent apoptosis in cells simultaneously exposed to the proliferation-stimulating effect of activated myc and the growth arresting signal of wt p53.


Asunto(s)
Apoptosis/fisiología , Genes myc/genética , Genes myc/fisiología , Linfoma de Células T/patología , Proteínas Proto-Oncogénicas/fisiología , Proteína p53 Supresora de Tumor/fisiología , Animales , Apoptosis/efectos de los fármacos , Linfoma de Burkitt/patología , División Celular , Regulación Neoplásica de la Expresión Génica , Ratones , Mutación , Pruebas de Precipitina , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-bcl-2 , Linfocitos T/química , Linfocitos T/efectos de los fármacos , Linfocitos T/patología , Temperatura , Transfección , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/análisis
8.
Oncogene ; 19(14): 1801-6, 2000 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-10777214

RESUMEN

EBNA-3 (also called EBNA-3A) is one of the EBV encoded nuclear antigens that are necessary for B-cell transformation. EBNA-3 is known to target RBPs, nuclear proteins that also interacts with EBNA-2, EBNA-4 and EBNA-6. In order to identify additional EBNA-3 targets, an EBV-transformed human lymphocyte cDNA library was screened in the yeast two-hybrid system with N-terminus truncated EBNA-3 that cannot interact with RBP-Jkappa. A clone, encoding Xap-2 protein, a cellular partner of Hepatitis B virus X-antigen was isolated. This protein is also known as the p38 subunit of the aryl hydrocarbon receptor complex (ARA9). The specific binding to EBNA-3 was confirmed by showing that the GST-Xap-2 precipitated EBNA-3 from CV1 cells that were infected with recombinant vaccinia virus expressing EBNA-3. Deletion of the C-terminus of Xap-2 eliminated the binding. Fusion with green fluorescent protein showed that Xap-2 is preferentially cytoplasmic but translocates to the nucleus upon expression of EBNA-3.


Asunto(s)
Antígenos Nucleares del Virus de Epstein-Barr/metabolismo , Antígenos de la Hepatitis B/metabolismo , Herpesvirus Humano 4/metabolismo , Proteínas/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Transactivadores/metabolismo , Células 3T3 , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Línea Celular , Línea Celular Transformada , ADN Complementario , Antígenos Nucleares del Virus de Epstein-Barr/genética , Herpesvirus Humano 4/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular , Ratones , Datos de Secuencia Molecular , Proteínas/genética , Receptores de Hidrocarburo de Aril/genética , Proteínas Recombinantes de Fusión/genética , Fracciones Subcelulares , Técnicas del Sistema de Dos Híbridos , Proteínas Reguladoras y Accesorias Virales
9.
Oncogene ; 8(6): 1495-500, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8502475

RESUMEN

All Burkitt lymphoma (BL) biopsies and cell lines carry a c-myc/Ig translocation. The resulting constitutive activation of c-myc is regarded as an essential factor for the progressive growth of the tumor cells. At least 60% of BL cell lines carry a mutated p53 gene as well. It has been shown that the growth of mutant p53 carrying tumor cells could be inhibited by the introduction of wild-type p53. In order to examine whether this also applies to the presumably 'myc-driven' BL cell, we have transfected the Epstein-Barr virus (EBV) negative BL41 cell line with a temperature sensitive p53 mutant (p53-Val135) that expresses p53 with a largely mutant conformation at 37.5 degrees C and mostly wild-type conformation at 32 degrees C. At 37.5 degrees C, the p53-Val135 transfected cells behaved like the parental or neo transfected control cells. However, expression of exogenous wild-type p53 at 32 degrees C resulted in a rapid reduction of the number of viable cells while the parental and neo control cells remained unaffected. Cell death was due to apoptosis as shown by chromatin and nuclear condensation and specific DNA fragmentation. The first signs of apoptosis were evident after 10 h at 32 degrees C and after 3 days 90-100% of the cells had undergone apoptosis. These findings indicate an incompatibility between expression of wild-type p53 and progressive growth of BL cells if their neoplastic development has included a p53 mutation. The question whether apoptosis was induced in by the wild-type protein per se or by the contradictory signals of a constitutively activated c-myc and wild-type p53 needs further investigation.


Asunto(s)
Apoptosis/genética , Linfoma de Burkitt/genética , Linfoma de Burkitt/patología , Genes p53 , Mutación , Secuencia de Bases , Biopsia , División Celular , Cromosomas Humanos Par 14 , Cromosomas Humanos Par 8 , ADN de Neoplasias/genética , Genes de Inmunoglobulinas , Genes myc , Humanos , Cadenas Pesadas de Inmunoglobulina , Cinética , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos , Reacción en Cadena de la Polimerasa , Transfección , Translocación Genética , Células Tumorales Cultivadas
10.
Oncogene ; 10(9): 1869-74, 1995 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-7753563

RESUMEN

Using immunofluorescence technique we have analysed the Rb, p53, EBNA-2 and EBNA-5 expression pattern in EBV infected human B-cells and established lymphoblastoid cell lines (LCL-s). Resting B-cells showed only a faint Rb and no p53 immunostaining. The expression of both Rb and p53 increased after EBV infection. The change was first detectable 6 h after infection. The frequency of brilliantly Rb positive cells increased more rapidly than p53 positives. EBNA-2 and EBNA-5 became first detectable 12 h after infection. The frequency of EBNA positive cells in the freshly infected cultures was concordant with the proportion of CD23 and PCNA positives, but remained consistently below the frequency of Rb and p53 positive cells. Double immunofluorescence staining showed that all EBNA-5 positive cells were strongly Rb and p53 positive. LCL-s did not stain for p53, whereas the Rb staining was maintained at a high level. The EBNA-5 staining pattern changed from brilliant almost homogeneous nuclear staining in the freshly infected B-cells, to a nonhomogeneous pattern with a small number of strongly fluorescent nuclear bodies in established LCL-s. There was no change in the EBNA-2 staining pattern. Our findings indicate that the immortalization of B-cells by EBV may initially involve a high expression of EBNA-5, p53 and Rb, but only cells with low p53 and focal expression of EBNA-5 in nuclear bodies have the selective advantage required to grow into immortalized lines.


Asunto(s)
Antígenos Virales/metabolismo , Linfocitos B/citología , Proteínas de Unión al ADN/metabolismo , Infecciones por Herpesviridae/metabolismo , Proteína de Retinoblastoma/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Infecciones Tumorales por Virus/metabolismo , Linfocitos B/metabolismo , Línea Celular , Antígenos Nucleares del Virus de Epstein-Barr , Técnica del Anticuerpo Fluorescente , Herpesvirus Humano 4 , Humanos , Antígeno Nuclear de Célula en Proliferación/metabolismo , Receptores de IgE/metabolismo , Factores de Tiempo
11.
J Comput Biol ; 1(2): 153-63, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8790461

RESUMEN

For a sequence of colors independently evolving on a tree under a simple Markov model, we consider conditions under which the tree can be uniquely recovered from the "sequence spectrum"-the expected frequencies of the various leaf colorations. This is relevant for phylogenetic analysis (where colors represent nucleotides or amino acids; leaves represent extant taxa) as the sequence spectrum is estimated directly from a collection of aligned sequences. Allowing the rate of the evolutionary process to vary across sites is an important extension over most previous studies-we show that, given suitable restrictions on the rate distribution, the true tree (up to the placement of its root) is uniquely identified by its sequence spectrum. However, if the rate distribution is unknown and arbitrary, then, for simple models, it is possible for every tree to produce the same sequence spectrum. Hence there is a logical barrier to accurate, consistent phylogenetic inference for these models when assumptions about the rate distribution are not made. This result exploits a novel theorem on the action of polynomials with non-negative coefficients on sequences.


Asunto(s)
Modelos Biológicos , Filogenia , Análisis de Secuencia , Cadenas de Markov , Reproducibilidad de los Resultados , Alineación de Secuencia
12.
Pediatrics ; 90(3): 380-4, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1518692

RESUMEN

Recurrent episodes of hypoxemia may affect the growth, cardiac function, neurologic outcome, and survival of infants with bronchopulmonary dysplasia (BPD). As oral feeding might stress these infants by compromising pulmonary function even after hospital discharge, we measured oxygen saturation (SaO2) via pulse oximetry before, during the initial 10 minutes of, and immediately after oral feeding in 11 patients with BPD, 12 very low birth weight infants, and 23 healthy full-term infants. All infants with BPD had been previously discharged from the hospital after weaning from supplemental oxygen. Studies were done at a mean postconceptional age of 43 weeks while the infants were fed at home by one of their parents. Levels of SaO2 for the three groups were comparable before and during feeds. After feeding, the infants with BPD had significantly lower mean levels of SaO2 (84 +/- 8% [SD] vs 93 +/- 4% and 93 +/- 3%, respectively; P less than .01). They also spent more time after feeding with an SaO2 less than 90% (64 +/- 34% of time vs 27 +/- 33% for the very low birth weight and 22 +/- 20% for the term group; P less than .01) and greater time with an SaO2 less than 80% (37 +/- 28% vs 4 +/- 10% and 4 +/- 8%, respectively; P less than .01). Desaturation in infants with BPD was related to larger volume and faster oral intake during feeding. Thus, the data indicate that desaturation after feeding remains a recurrent problem for survivors of BPD after discharge.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Displasia Broncopulmonar/sangre , Ingestión de Alimentos , Recién Nacido de Bajo Peso , Enfermedades del Prematuro/sangre , Recien Nacido Prematuro , Oxígeno/sangre , Peso Corporal , Estudios de Seguimiento , Edad Gestacional , Humanos , Alimentos Infantiles , Recién Nacido , Oximetría , Factores de Tiempo
13.
J Thorac Cardiovasc Surg ; 115(3): 517-25; discussion 525-7, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9535437

RESUMEN

OBJECTIVE: A prospective randomized study was performed to test whether removal of endothelin-1, by ultrafiltration techniques, will reduce pulmonary hypertension after operations for congenital heart disease. METHODS: Twenty-four patients with pulmonary hypertension (systolic pulmonary/systemic arterial pressure ratio > 60%) undergoing cardiac operations were randomized into a control group (n = 12) having conventional ultrafiltration and an experimental group (n = 12) undergoing dilutional ultrafiltration during and modified ultrafiltration after cardiopulmonary bypass. Plasma endothelin-1, nitric oxide metabolites, and cyclic guanosine monophosphate were assayed before bypass, 10 minutes into bypass, after bypass, and 0, 3, 6, and 12 hours after the operation in both groups, as well as in the ultrafiltrates and after modified ultrafiltration in the experimental group. Both groups received alpha-blockers (chlorpromazine and/or prazosin) postoperatively using the same guidelines. RESULTS: The ultrafiltrates contained significant amounts of endothelin-1 (1.81 +/- 0.86 pg/ml, dilutional, and 6.44 +/- 1.82 pg/ml, modified ultrafiltrate). Endothelin-1 and the pulmonary/systemic pressure ratio were significantly lower in experimental compared with control patients. Nitric oxide metabolites and cyclic guanosine monophosphate increased similarly in both groups for 12 hours after the operation (p = not significant). Three of 12 control patients (25%) but no experimental patients had pulmonary hypertensive crises (p = 0.07). The experimental patients required significantly less ventilatory support (67 +/- 47 hours vs 178 +/- 139 hours for control patients, p = 0.048). CONCLUSIONS: Dilutional and modified ultrafiltration reduce endothelin-1 and the pulmonary/systemic pressure ratio postoperatively and may become an important adjunct for preventing pulmonary hypertension after operations for congenital heart disease in high-risk patients.


Asunto(s)
Cardiopatías Congénitas/cirugía , Hemofiltración , Hipertensión Pulmonar/prevención & control , Complicaciones Posoperatorias/prevención & control , Puente Cardiopulmonar , GMP Cíclico/sangre , Endotelina-1/sangre , Femenino , Cardiopatías Congénitas/sangre , Hemofiltración/métodos , Humanos , Hipertensión Pulmonar/sangre , Hipertensión Pulmonar/etiología , Lactante , Masculino , Óxido Nítrico/sangre , Estudios Prospectivos
14.
Chest ; 111(3): 550-8, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9118686

RESUMEN

Bilateral volume reduction surgery (VRS) improves lung function for selected patients with emphysema. However, predictors of outcome are not well defined. We reviewed the preoperative characteristics of the first 47 consecutive patients who underwent bilateral VRS at the Massachusetts General Hospital in order to define potential predictors of unacceptable outcome. Preoperative data included spirometry, plethysmography, diffusion of carbon monoxide (Dco), maximum inspiratory pressure (MIP), maximum expiratory pressure, resting arterial blood gases (ABG), cardiopulmonary exercise testing with ABG and lactate sampling, and radionuclide ventriculography. Prepulmonary and postpulmonary rehabilitation 6-min walk tets (6MWT), and preoperative chest CT scans were also obtained. Twenty-two subjects were male and 17 of the subjects were on the lung transplant list. Patient characteristics included age of 60.5 +/- 7.5 years, FEV1 of 0.67 +/- 0.20 L, total lung capacity of 7.56 +/- 1.7 L, Dco of 7.40 +/- 4.1 mL/min/mm Hg, and PaCO2 of 41.6 +/- 6.4 mm Hg (mean +/- SD). The FEV1, vital capacity, MIP, resting room air PaCO2, prepulmonary and postpulmonary rehabilitation 6MWT, and PaCO2 at maximum oxygen consumption correlated with length of hospitalization (p < 0.05). Based on analysis of 41 of 47 patients for whom there were complete data, the inability to walk more than 200 m on the 6MWT before or after preoperative pulmonary rehabilitation, and resting PaCO2 > or = 45 mm Hg were the best predictors of an unacceptable outcome. If either of these characteristics was present, six of 16 vs zero of 25 died (Fisher's Exact Test, p = 0.0025, one-tailed) and 11 of 16 vs four of 25 had hospital courses > 21 days (p < 0.002). Both the 6MWT < 200 m and resting PaCO2 > or = 45 mm Hg alone correlated with death (p = 0.004 and p = 0.012, respectively) and the resting PaCO2 > or = 45 mm Hg correlated with hospital days > 21 (p = 0.0002). In conclusion, the data suggest that the inability to walk at least 200 m in 6 min before or after pulmonary rehabilitation and a resting room air PaCO2 > or = 45 mm Hg are excellent preoperative predictors of unacceptable postoperative outcomes.


Asunto(s)
Enfermedades Pulmonares Obstructivas/cirugía , Pulmón/cirugía , Complicaciones Posoperatorias , Prueba de Esfuerzo , Femenino , Humanos , Tiempo de Internación , Enfermedades Pulmonares Obstructivas/mortalidad , Enfermedades Pulmonares Obstructivas/fisiopatología , Masculino , Persona de Mediana Edad , Pruebas de Función Respiratoria , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento
15.
Ann Thorac Surg ; 66(2): 500-5, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9725392

RESUMEN

BACKGROUND: Adrenomedullin is a newly identified peptide with profound hypotensive effects. We investigated perioperative adrenomedullin levels among patients with congenital heart disease with and without pulmonary hypertension. METHODS: Levels of plasma adrenomedullin, endothelin-1, and nitric oxide metabolites were measured in three groups: (1) low pulmonary flow (n=11); (2) high flow/low pulmonary arterial pressure (less than 60% systemic pressure) (n=9); and (3) high flow/high pressure (n=10). Samples were obtained preoperatively, on and off pump, and 3, 6, and 12 hours after bypass. RESULTS: Adrenomedullin levels were highest in the low pulmonary flow group (189.7+/-15 pg/mL low flow versus 103.1+/-9.5 pg/mL high flow/low pulmonary and 139+/-17.5 pg/mL high flow/high pressure at 12 hours; p < or = 0.05). The arterial pressure/systemic pressure remained significantly lower in the high flow/low pulmonary pressure compared with the high flow/high pressure group (0.37+/-0.08 versus 0.62+/-0.11; p < 0.005). Perioperative endothelin-1 and nitric oxide levels remained low in the low pulmonary flow group but increased progressively in both high flow groups. CONCLUSIONS: Circulating plasma adrenomedullin appears to affect baseline vascular tone in patients with intact endothelial function. It may interact with nitric oxide and endothelin-1 to help regulate blood pressure perioperatively in patients with congenital heart disease.


Asunto(s)
Cardiopatías Congénitas/complicaciones , Hipertensión Pulmonar/etiología , Péptidos/sangre , Adrenomedulina , Presión Sanguínea , Preescolar , Endotelina-1/sangre , Femenino , Cardiopatías Congénitas/sangre , Cardiopatías Congénitas/cirugía , Humanos , Masculino , Óxido Nítrico/sangre , Circulación Pulmonar/fisiología , Factores de Riesgo
16.
Ann Thorac Surg ; 66(3): 821-7; discussion 828, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9768937

RESUMEN

BACKGROUND: Modified ultrafiltration (MUF) after cardiopulmonary bypass (CPB) in children decreases body water, removes inflammatory mediators, improves hemodynamics, and decreases transfusion requirements. The optimal target population for MUF needs to be defined. This prospective, randomized study attempted to identify the best candidates for MUF during operations for congenital heart disease. METHODS: Informed consent was obtained from 100 consecutive patients with complex congenital heart disease undergoing operations with CPB. They were randomized into a control group (n = 50) of conventional ultrafiltration during bypass and an experimental group using dilutional ultrafiltration during bypass and venovenous modified ultrafiltration after bypass (MUF group, n = 50). Postoperative arterial oxygenation, duration of ventilatory support, transfusion requirements, hematocrit, chest tube output, and time to chest tube removal were compared between the groups stratified by age and weight, CPB technique, existence of preoperative pulmonary hypertension, and diagnosis. RESULTS: There were no MUF-related complications. In patients with preoperative pulmonary hypertension, MUF significantly improved postoperative oxygenation (445 +/- 129 mm Hg versus control: 307 +/- 113 mm Hg, p = 0.002), shortened ventilatory support (42.9 +/- 29.5 hours versus control: 162.4 +/- 131.2 hours, p = 0.0005), decreased blood transfusion (red blood cells: 16.2 +/- 18.2 mL/kg versus control: 41.4 +/- 27.8 mL/kg, p = 0.01; coagulation factors: 5.3. +/- 6.9 mL/kg versus control: 32.3 +/- 15.5 mL/kg, p = 0.01), and led to earlier chest tube removal. In neonates (< or =30 days), MUF significantly reduced transfusion of coagulation factors (5.4 +/- 5.0 mL/kg versus control: 39.9 +/- 25.8 mL/kg, p = 0.007), and duration of ventilatory support (59.3 +/- 36.2 hours versus 242.1 +/- 143.1 hours, p = 0.0009). In patients with prolonged CPB (>120 minutes), MUF significantly reduced the duration of ventilatory support (44.7 +/- 37.0 hours versus 128.7 +/- 133.4 hours, p = 0.002). No significant differences were observed between MUF and control patients for any parameter in the presence of ventricular septal defect without pulmonary hypertension, tetralogy of Fallot, or aortic stenosis. CONCLUSIONS: Modified ultrafiltration after CPB is safe and decreases the need for homologous blood transfusion, the duration of ventilatory support, and chest tube placement in selected patients with complex congenital heart disease. The optimal use of MUF includes patients with preoperative pulmonary hypertension, neonates, and patients who require prolonged CPB.


Asunto(s)
Cardiopatías Congénitas/cirugía , Hemofiltración/métodos , Pérdida de Sangre Quirúrgica/prevención & control , Puente Cardiopulmonar , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Respiración Artificial
17.
J Virol Methods ; 73(1): 89-97, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9705180

RESUMEN

Simultaneous detection of two antigens by immunostaining usually requires primary antibodies from two different species or a hapten modification of one of the antibodies if they are from the same species. A novel double staining method is described for immunodetection of two independent antigens using two mouse monoclonal antibodies. The principle of the method is the following: The first antigen is detected by a monoclonal antibody that is diluted so extensively that it cannot be recognized with conventional detection systems. A highly sensitive biotin-tyramide amplification system is used to identify this antibody. The second antigen is stained with a monoclonal antibody by dilution and detected by conventional immunostaining. The method was tested for both alkaline-phosphatase staining on paraffin sections and immunofluorescence staining on cultured cells in cytospin preparation. The absence of cross-reaction in the former system was demonstrated by the mutually exclusive detection of T- and B-cells in human lymph nodes or T-cells and carcinoma cells in nasopharyngeal carcinoma biopsies. Similarly, the EBV encoded EBNA2 and ZEBRA proteins showed a mutually exclusive staining by immunofluorescence on B95-8 cells. The method could be used to demonstrate co-expression of two independent antigens in the same cells, such as PCNA and keratin in carcinoma cells in paraffin sections and for EBNA2 and LMP1 EBV proteins in immunofluorescence preparations of B95-8 cells.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos/análisis , Técnica del Anticuerpo Fluorescente , Técnicas para Inmunoenzimas , Fosfatasa Alcalina , Animales , Antígenos/inmunología , Antígenos CD/análisis , Antígenos Virales/análisis , Biotina/análogos & derivados , Reacciones Cruzadas , Herpesvirus Humano 4/inmunología , Humanos , Queratinas/análisis , Queratinas/inmunología , Neoplasias Pulmonares , Tejido Linfoide , Ratones , Neoplasias Nasofaríngeas , Adhesión en Parafina , Antígeno Nuclear de Célula en Proliferación/análisis , Células Tumorales Cultivadas , Tiramina/análogos & derivados
18.
J Dev Behav Pediatr ; 17(2): 69-76, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8727839

RESUMEN

Infants with very low birth weight (VLBW) are at increased risk for feeding disorders that can affect growth and development. One hundred and forty one mother-infant pairs were compared [55 with infants with high medical risk due to infant VLBW and bronchopulmonary dysplasia (BPD), 34 VLBW without BPD, and 52 term infants] on operationally defined measures of feeding behaviors and maternal self-report of depression and anxiety. Mothers of VLBW infants with and without BPD spent more time prompting their infants to feed when their infants engaged in nonfeeding behavior. Despite increased maternal efforts, infants with BPD took in less formula, spent less time sucking, and spent a greater proportion of time nonfeeding. VLBW infants without BPD were equivalent to term infants in percentage of time sucking and in volume of formula ingested and were more likely to take in higher calories than infants with BPD. Mothers of VLBW infants with and without BPD were also more likely to report clinically significant symptoms of depression and anxiety than mothers of term infants. Because mothers of VLBW infants who were more depressed or anxious were less likely to verbally prompt their infants to eat, maternal psychological symptoms should be considered in assessing interactions of VLBW mother-infant dyads.


Asunto(s)
Alimentación con Biberón/psicología , Displasia Broncopulmonar/psicología , Cuidado del Lactante/psicología , Recién Nacido de muy Bajo Peso/psicología , Relaciones Madre-Hijo , Conducta en la Lactancia , Adulto , Ansiedad/psicología , Displasia Broncopulmonar/rehabilitación , Depresión/psicología , Ingestión de Energía , Femenino , Humanos , Recién Nacido , Masculino , Conducta Materna , Madres/psicología , Determinación de la Personalidad , Conducta Verbal , Aumento de Peso
19.
J Dev Behav Pediatr ; 12(2): 115-20, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2045484

RESUMEN

Four children with cystic fibrosis, ranging in age from 10 to 40 months, were admitted to a specialized pediatric unit for evaluation and treatment of malnutrition. All were below the fifth percentile for weight despite appropriate pancreatic enzyme replacement and outpatient nutritional counseling. Dietary evaluation revealed oral intake of 48% to 62% of that required for growth. Standardized nursing and psychological assessments of feeding behaviors during meals indicated a low acceptance rate of foods and a high rate of maladaptive feeding behaviors. Treatment consisted of behavioral management using positive reinforcement of food acceptance, extinction of negative behaviors, and parent training. Mean percentage of caloric intake increased from 54% to 92% for the four patients. At long-term follow-up, the patients who continued the program demonstrated substantial and persistent catch-up growth. Behavioral feeding disorders may contribute to failure to thrive in patients with cystic fibrosis and must be considered when growth failure occurs despite correct medical management and apparently mild pulmonary and gastrointestinal involvement.


Asunto(s)
Terapia Conductista/métodos , Trastornos de la Nutrición del Niño/terapia , Fibrosis Quística/complicaciones , Insuficiencia de Crecimiento/terapia , Peso Corporal , Trastornos de la Nutrición del Niño/psicología , Preescolar , Fibrosis Quística/psicología , Insuficiencia de Crecimiento/psicología , Conducta Alimentaria , Femenino , Estudios de Seguimiento , Hospitalización , Humanos , Lactante , Masculino , Medio Social
20.
Clin Pediatr (Phila) ; 40(1): 27-33, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11210083

RESUMEN

This paper acquaints pediatricians and health care personnel with the triad of poor weight gain, frequent breastfeeding, and food refusal in infants during the second 6 months of life. The histories of six infants aged 8-11 months, with failure to thrive, food refusal, and frequent breastfeeding, are presented. All the mothers were facing significant stresses, which may have decreased their breast milk supply, and were leading them to use breastfeeding for their comfort and/or the comfort of their infant. The infants responded with continued frequent breastfeeding, refusal of complementary foods, and decreased weight gain. These infants fit the characteristics of the vulerable child syndrome. Treatment of these infants required evaluation and treatment of the mothers' psychosocial issues along with a behavioral feeding program. Even with this multidisciplinary approach, these infants showed very slow catch-up growth. Pediatricians and health care personnel should use and build on this information in the evaluation and treatment of infants with similar problems.


Asunto(s)
Lactancia Materna , Alimentos Infantiles , Lactancia Materna/psicología , Insuficiencia de Crecimiento , Femenino , Humanos , Lactante , Lactancia/fisiología , Masculino , Relaciones Madre-Hijo
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