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1.
Clin Microbiol Infect ; 27(2): 283.e9-283.e16, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32470569

RESUMO

OBJECTIVES: During the last decade, some changes in the epidemiology of invasive infections have been reported; however, specific studies with patient-level data are scarce. The aim of this study was to describe and evaluate the epidemiologic changes in bloodstream infections (BSI) during the last decade in Andalucía, Spain. METHODS: Data from two prospective cohorts of BSI in adults with the same methodology performed 10 years apart in 11 hospitals (eight tertiary and three community) in Andalucía, Spain, were compared; the 2006-7 cohort study was performed between October 2006 and March 2007, and the 2016-17 cohort study was performed between October 2016 and March 2017. Population-based incidence rates were calculated and extrapolated for 1 year. Relative risk ratios were calculated between the 2 periods. Multivariate analyses were performed by logistic regression. RESULTS: Overall, 1262 episodes of BSI were included, 563 (44.6%) in 2006-7 and 699 (55.3%) in 2016-17. Multivariate models selected the following changes in patients' features in 2016-17, after controlling for type of acquisition: higher age (odds ratio (OR) = 1.02; 95% confidence interval [CI] 1.01-1.03), lower urinary catheter (OR = 0.37; 95% CI, 0.26-0.48) and lower Pitt score (OR = 0.76; 95% CI, 0.71-0.82). Adjusted estimations considering patients' features and exposure to procedures showed a reduction in coagulase-negative staphylococci (OR = 0.47; 95% CI, 0.32-0.69), and an increase in Proteus spp. (OR = 3.12; 95% CI, 1.18-8.23) and Candida spp. (OR = 3.01; 95% CI, 1.03-8.86). CONCLUSIONS: We found relevant epidemiologic changes in BSI in our area, including rates, frequency of acquisition types, changes in patient's profiles and aetiologic agents.


Assuntos
Infecções Bacterianas/epidemiologia , Micoses/epidemiologia , Sepse/microbiologia , Idoso , Infecções Bacterianas/mortalidade , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Mortalidade , Micoses/mortalidade , Estudos Prospectivos , Fatores de Risco , Sepse/epidemiologia , Sepse/mortalidade , Espanha/epidemiologia
2.
Rev Esp Anestesiol Reanim (Engl Ed) ; 65(1): 31-40, 2018 Jan.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28987399

RESUMO

The management of difficult airway (DA) in thoracic surgery is more difficult due to the need for lung separation or isolation and frequent presence of associated upper and lower airway problems. We performed an article review analysing 818 papers published with clinical evidence indexed in Pubmed that allowed us to develop an algorithm. The best airway management in predicted DA is tracheal intubation and independent bronchial blockers guided by fibroscopy maintaining spontaneous ventilation. For unpredicted DA, the use of videolaryngoscopes is recommended initially, and adequate neuromuscular relaxation (rocuronium/sugammadex), among other maneuvers. In both cases, double lumen tubes should be reserved for when lung separation is absolutely indicated. Finally, extubation should be a time of maximum care and be performed according to the safety measures of the Difficult Arway Society.


Assuntos
Manuseio das Vias Aéreas/métodos , Procedimentos Cirúrgicos Torácicos , Algoritmos , Humanos , Intubação Intratraqueal , Pulmão/cirurgia
3.
Arch Soc Esp Oftalmol ; 90(12): 562-5, 2015 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26279484

RESUMO

OBJECTIVE: To determine the importance of intratumoral genetic analysis in the diagnosis of germ-line mutations in patients with retinoblastoma. To underline the importance of performing these genetic tests in every case of retinoblastoma. METHOD: Intratumoral genetic analysis of RB1 mutation was performed on 17 enucleated eyes that were non-responsive to conservative treatment. Patients had no family history of retinoblastoma, and lesions were always single. The identified mutations were then also studied in peripheral blood analysis. RESULTS: There were 12 (70.6%) cases with positive results in intratumoral analysis. In 8 cases (47.1%) mutation of both RB1 alelli were detected, and in 4 (23.5%) cases only one allele was found mutated. In 5 patients (29.4%) no mutation was identified. In the first hit, mutations comprised 7 frameshift or nonsense and 2 splice, whereas in the second hit, one splice mutation, 2 nonsense and 8 loss of heterozygosity were identified. Among 6 patients where intratumoral analysis detected a single mutation associated with a loss of heterozygosity, the peripheral blood analysis was able to detect the same mutation in 3 cases (50%). CONCLUSIONS: Intratumoral genetic analysis of sporadic retinoblastoma can detect germ-line mutations. These patients are at higher risk of bilateralization and development of second tumors or trilateral retinoblastoma. Genetic screening is recommended in every patient diagnosed with retinoblastoma.


Assuntos
Neoplasias Oculares/genética , Mutação , Retinoblastoma/genética , Alelos , Análise Mutacional de DNA , Enucleação Ocular , Neoplasias Oculares/sangue , Neoplasias Oculares/química , Neoplasias Oculares/cirurgia , Genes do Retinoblastoma , Testes Genéticos , Mutação em Linhagem Germinativa , Humanos , Perda de Heterozigosidade , Proteínas de Neoplasias/sangue , Proteínas de Neoplasias/genética , Especificidade de Órgãos , Retinoblastoma/sangue , Retinoblastoma/química , Retinoblastoma/cirurgia , Proteínas de Ligação a Retinoblastoma/análise , Proteínas de Ligação a Retinoblastoma/sangue , Proteínas de Ligação a Retinoblastoma/genética , Proteína do Retinoblastoma/sangue , Proteína do Retinoblastoma/genética , Ubiquitina-Proteína Ligases/análise , Ubiquitina-Proteína Ligases/sangue , Ubiquitina-Proteína Ligases/genética
4.
Arch Soc Esp Oftalmol ; 90(9): 414-20, 2015 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-25817468

RESUMO

OBJECTIVE: To analyze the genetic alterations identified in the RB1 gene in retinoblastoma patients who do not respond to systemic chemotherapy. METHODS: A genetic analysis was performed on 115 patients with retinoblastoma, 40 of whom had received systemic chemotherapy, and 29 of them had bilateral disease. Descriptive and retrospective study. Non-responders were considered as patients who are finally enucleated. RESULTS: Patients with deletion type mutations are those with less preservation of the eyeball (Pearson Chi-square, P=.055). Patients with an impaired nonsense-frameshift type are more likely to preserve the eyeball. Of the 3 patients who had undergone bilateral enucleation, 2 of them had deletions and one missense alteration. Survival analysis (Kaplan-Meier curve) shows that patients with deletion type mutations are more resistance to chemotherapy, are suffering higher rates of enucleation, and for a shorter period of time (log rank [Mantel-Cox] with a significance level of P=.053), which are also associated with increased rate of being bilateral. CONCLUSIONS: Patients with a genotype show increased resistance to chemotherapy should be evaluated more closely and treated with various therapeutic weapons early. Patients that have deletions in the RB1 gene are at increased risk of chemoresistance. It is likely that other genetic alterations other than RB1 gene may be related to tumor aggressiveness and treatment resistance.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mutação , Neoplasias da Retina/genética , Proteínas de Ligação a Retinoblastoma/genética , Retinoblastoma/genética , Ubiquitina-Proteína Ligases/genética , Análise Mutacional de DNA , Resistencia a Medicamentos Antineoplásicos , Enucleação Ocular , Feminino , Genótipo , Humanos , Estimativa de Kaplan-Meier , Masculino , Invasividade Neoplásica , Neoplasias Primárias Múltiplas/tratamento farmacológico , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/cirurgia , Modelos de Riscos Proporcionais , Neoplasias da Retina/tratamento farmacológico , Neoplasias da Retina/cirurgia , Retinoblastoma/tratamento farmacológico , Retinoblastoma/cirurgia , Estudos Retrospectivos , Deleção de Sequência
5.
Acta Ortop Mex ; 29(1): 46-8, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-26999926

RESUMO

Femoroacetabular impingement is the mechanical contact between the femur and the pelvis, frequently between the femur neck and the acetabular rim, whether due to a deformity of the former (cam type) or the latter (pincer type). However, there may be extraarticular causes of impingement. Together with the increased diagnosis of impingement, arthroscopic treatment is increasingly frequent and has become the standard treatment. This report analyzes a case of extraarticular hip impingement caused by contact between the femur and a prominent anteroinferior iliac spine (AIIS), probably due to a healed old avulsion and its later arthroscopic management.


Assuntos
Artroscopia/métodos , Impacto Femoroacetabular/cirurgia , Fêmur/diagnóstico por imagem , Adulto , Impacto Femoroacetabular/diagnóstico , Impacto Femoroacetabular/diagnóstico por imagem , Humanos , Masculino , Pelve/diagnóstico por imagem , Tomografia Computadorizada por Raios X
6.
Arch Soc Esp Oftalmol ; 89(1): 4-9, 2014 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-24269417

RESUMO

OBJETIVE: To determine the correlation between the presence of genetic anomalies identified in the RB1 gene and the development of trilateral retinoblastoma. METHOD: No patients with primitive neuroectodermal tumour (PNET) were identified out of a total of 206 patients, but there were 17 cases of pineal cysts, of which 11 had a genetic study. RESULTS: Of the 11 patients who had a genetic study performed, the anomaly in the germinal line was identified in 8 cases, which was equivalent to 100% of the bilateral retinoblastomas, and 25% of the unilateral ones. It is more common to find a germinal mutation in patients with bilateral disease (P=.024). There are no significant differences in the type of anomaly identified, although the nonsense-frameshift type is more frequent in cases with bilateral involvement. Identification of the genetic anomaly is more frequent in patients who have pineal cysts (Fisher test; P=.490). Nine of the 17 patients received systemic chemotherapy (52.29% of the cases), which could be able to prevent the development of PNET. Although a certain trend was observed in all the mentioned parameters, there was a relationship between, the presence of pineal cysts and bilateral disease (Pearson Chi X2: P=.191), a known family history (Fisher test; P=.114) and age of early diagnosis (Fisher test; P=.114). There were no significant differences in the mutation type identified. CONCLUSIONS: Considering pineal cysts as a pre-malignant form of pinealoblastoma, we found a relationship between the germinal line mutation of the RB1 gene and the cases with bilateral or unilateral retinoblastoma.


Assuntos
Cistos/genética , Genes do Retinoblastoma , Mutação em Linhagem Germinativa , Neoplasias Primárias Múltiplas/genética , Glândula Pineal/patologia , Neoplasias da Retina/genética , Retinoblastoma/genética , Adenoma/epidemiologia , Adenoma/genética , Antineoplásicos/uso terapêutico , Malformação de Arnold-Chiari/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/prevenção & controle , Malformações Vasculares do Sistema Nervoso Central/genética , Cistos/epidemiologia , Cistos/patologia , Mutação da Fase de Leitura , Humanos , Neoplasias Primárias Múltiplas/patologia , Tumores Neuroectodérmicos Primitivos/genética , Tumores Neuroectodérmicos Primitivos/prevenção & controle , Pinealoma/genética , Pinealoma/prevenção & controle , Neoplasias Hipofisárias/genética , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Estudos Retrospectivos
7.
Actas Urol Esp ; 34(9): 802-5, 2010 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-20843459

RESUMO

INTRODUCTION: We evaluate the effectiveness of REMEEX® (readjustable sling) for the treatment of male urinary stress incontinence (SUI). MATERIALS AND METHOD: Between February 2007 and December 2009, 14 male patients with mild to severe SUI were operated with the use of REMEEX® system. The origin of incontinence was radical open prostatectomy (n=9), laparoscopic prostatectomy (n=4) and TUR (n=1). We evaluate postoperatively complications in three groups: intraoperatively, early complications (before 1 month) and late complications (after 1 month). Follow up was done at 1, 3, 6 and 12 months after intervention. RESULTS: The mean age was 68,5 years (range: 62-71). The average follow-up time was 18,6 months (range: 10,1-35,2). The mean of readjustment was 3,7 (range: 1-6). Twelve patients were readjusted during the early period (24-72h after intervention). The mesh was removed in 3 cases (21,4%) owing to infection in one and the others because patients didn't want more system readjustment. There were four (28,5%) intraoperative bladder perforations. The early complication more frequent was acute urinary retention with five cases (35,7%). To the year of follow-up 41,7% of the patients are totally continent (5/12) and 33,3% presents light urinary incontinence (4/12). CONCLUSIONS: The REMEEX® system for the treatment of male SUI presents (in our experience) a 75% of good results (continent patients or patients with light urinary incontinence) at the year of follow-up with a high rate of light complications. Readjustment are frequent at the first six months after intervention and it's necessary an intense follow-up. We need more studies that evaluate the long-term efficiency of this system.


Assuntos
Slings Suburetrais , Incontinência Urinária por Estresse/cirurgia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Neurocirugia (Astur) ; 20(4): 367-71, 2009 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-19688138

RESUMO

Endodermal cysts (EC) of the central nervous system are very uncommon lesions predominantly located in the spinal canal. Although rare, intracranial EC have been mainly described in the posterior fossa, with the supratentorial location considered exceptional. Apart from the low frequency of these lesions, their pathoembriology still remais unknown. We report a patient with a huge frontal EC and review the literature. A 62-year-old man presented with abnormal behaviour, disorientation and decreased level of consciousness after moderate head injury. Initial cranial CT scan revealed a large cyst in the left frontal region with marked midline shift. Emergency puncture and decompression of the cyst demonstrated a milky fluid with high protein levels. Cranial MRI after patient improvement confirmed the existence of the cystic lesion with less mass effect. Delayed surgery was performed with craniotomy and total removal of the cyst. Pathological examination confirmed the presence of a typical EC. Patient made a complete recovery on follow-up with no recurrence on postoperative MRIs. Differential diagnosis of EC based on radiological data is quite difficult. As aggresive behaviour of this condition has been described following incomplete resections, the treatment of choice is a radical removal of the cyst in one or two stages depending on patient clinical condition.


Assuntos
Cistos do Sistema Nervoso Central/diagnóstico , Endoderma/patologia , Lobo Frontal/patologia , Neoplasias Supratentoriais/diagnóstico , Cistos do Sistema Nervoso Central/complicações , Cistos do Sistema Nervoso Central/diagnóstico por imagem , Cistos do Sistema Nervoso Central/embriologia , Cistos do Sistema Nervoso Central/cirurgia , Confusão/etiologia , Traumatismos Craniocerebrais/complicações , Traumatismos Craniocerebrais/diagnóstico por imagem , Craniotomia , Emergências , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/cirurgia , Humanos , Achados Incidentais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Agitação Psicomotora/etiologia , Neoplasias Supratentoriais/complicações , Neoplasias Supratentoriais/diagnóstico por imagem , Neoplasias Supratentoriais/embriologia , Neoplasias Supratentoriais/cirurgia , Tomografia Computadorizada por Raios X
9.
Neurocirugia (Astur) ; 19(4): 332-7, 2008 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-18726043

RESUMO

Radiation induced tumors are well-known but rare complications of radiotherapy. Meningiomas are the most common radiation-induced (RI) cranial tumors, followed by gliomas and sarcomas, while other tumors as haemangioblastomas remain extremely exceptional. We present 7 patients with RI brain tumors diagnosed and treated at our institution between 1990 and 2006. Retrospective review of their clinical charts is supplied. All patients were irradiated during childhood as a treatment for another disease, and fulfilled the criteria of RI neoplasia. Four patients developed meningiomas and three developed other tumors (one glioblastoma, one softtissue sarcoma and one hemangioblastoma). In all cases a complete surgical removal was achieved. Preoperative assessment based on MRI supplied the correct diagnosis in six patients. The most important risks factors described in the literature for developing RI tumors are the age at which radiotherapy was administered and the dose of radiation applied. Differential diagnosis of RI tumors includes any tumor appearing after radiotheraphy, especially recurrences of the primary disease, as RI neoplasias are a rare complication. Even in cases with complete surgical resection, prognosis of this clinical entity is basically related to the histology of the RI tumor.


Assuntos
Irradiação Craniana/efeitos adversos , Neoplasias Induzidas por Radiação , Radioterapia/efeitos adversos , Adolescente , Adulto , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/diagnóstico , Neoplasias Induzidas por Radiação/patologia , Prognóstico , Estudos Retrospectivos
10.
Arch Soc Esp Oftalmol ; 82(2): 73-9, 2007 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-17323246

RESUMO

OBJECTIVE: To describe an epidemic nosocomial outbreak of keratoconjunctivitis affecting at least 43 people in a Neonatal Intensive Care Unit in Madrid, between May and October 2002, perform epidemiologic research and determine preventive measures to prevent new outbreaks. METHODS: Description of the outbreak, clinical case definition, microbiologic and epidemiologic research through the use of questionnaires. Analysis of the incidence of subepithelial infiltrates 1 year after infection and the use of topical corticosteroid therapy. RESULTS: The epidemic began in the Neonatal Service, with a pair of twins being found as the initial focus. Dissemination occurred to about 24 workers of the unit, and 19 workers from other services. The microbiologic diagnosis confirmed adenovirus in 10 conjunctival smears and one serologically, with the remainder obeying clinical and epidemiological criteria of such infection. Infected patients using topical corticosteroids had a higher incidence of infiltrates 12 months later than those not using such agents (p=0.003 in Fisher test). CONCLUSIONS: Epidemic keratoconjunctivitis occurs frequently, is highly contagious and has possible long-term sequelae, necessitating the use of preventive measures to avoid spread and new outbreaks.


Assuntos
Conjuntivite/epidemiologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Unidades de Terapia Intensiva Neonatal , Ceratite/epidemiologia , Adulto , Conjuntivite/complicações , Feminino , Humanos , Ceratite/complicações , Masculino
11.
Arch Soc Esp Oftalmol ; 81(3): 165-8, 2006 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-16572361

RESUMO

CASE REPORT: A 37-year-old psychotic patient inflicted injuries to his skin and eyes in the context of an interpretational delirium with aesthetic content. He used magnifying glasses to concentrate sunlight and suffered burns to his arms and face. In the eyes, these resulted in massive iridial atrophy with loss of the sphincteric function, photic maculopathy and peripheral retinal coagulation. The macular lesion resolved spontaneously although he did not recover visual acuity. DISCUSSION: This is the first reported case of ocular self-injury secondary to sunlight. It is also the first case reporting retinal photo-coagulative lesions secondary to sunlight.


Assuntos
Queimaduras Oculares/etiologia , Doenças da Íris/etiologia , Iris/lesões , Transtornos Psicóticos/complicações , Doenças Retinianas/etiologia , Adulto , Queimaduras Oculares/diagnóstico , Angiofluoresceinografia , Fundo de Olho , Humanos , Doenças da Íris/diagnóstico , Macula Lutea/patologia , Masculino , Doenças Retinianas/diagnóstico , Acuidade Visual
12.
Arch Soc Esp Oftalmol ; 80(6): 331-8, 2005 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-15986273

RESUMO

UNLABELLED: PURPOSE, MATERIAL AND METHODS: To present the experience in management of orbital rhabdomiosarcoma over 21 years in our centre. Review of the 12 cases of paediatric rhabdomiosarcoma and results of treatment in terms of mortality and morbidity comparing our results with other studies. RESULTS/CONCLUSION: Management of orbital rhabdomyosarcoma following the European Protocol leads to poor results compared with the American protocol. Early radiotherapy and complete tumoral excision could play a role in management of this tumour


Assuntos
Neoplasias Orbitárias/terapia , Rabdomiossarcoma Embrionário/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Quimioterapia Adjuvante , Criança , Pré-Escolar , Protocolos Clínicos , Terapia Combinada , Irradiação Craniana , Dactinomicina/administração & dosagem , Intervalo Livre de Doença , Epirubicina/administração & dosagem , Etoposídeo/administração & dosagem , Enucleação Ocular , Feminino , Seguimentos , Humanos , Ifosfamida/administração & dosagem , Lactente , Tábuas de Vida , Masculino , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Neoplasias Orbitárias/tratamento farmacológico , Neoplasias Orbitárias/mortalidade , Neoplasias Orbitárias/patologia , Neoplasias Orbitárias/radioterapia , Neoplasias Orbitárias/cirurgia , Lesões por Radiação/etiologia , Radioterapia Adjuvante/efeitos adversos , Reoperação , Rabdomiossarcoma Embrionário/tratamento farmacológico , Rabdomiossarcoma Embrionário/mortalidade , Rabdomiossarcoma Embrionário/patologia , Rabdomiossarcoma Embrionário/radioterapia , Rabdomiossarcoma Embrionário/cirurgia , Análise de Sobrevida , Resultado do Tratamento , Vincristina/administração & dosagem
15.
Actas Esp Psiquiatr ; 30(6): 382-91, 2002.
Artigo em Espanhol | MEDLINE | ID: mdl-12487949

RESUMO

The history of estrangement as a clinical object is very recent and concrete. It is negatively defined through the following syndromes: depersonalization, derealization and disturbances of the self. The limits that are established for its definition are very lax and unsuitable. The models that have been applied to these phenomena are explained in this paper: the model of the psychology of faculties, the model of the self-awareness as a reflective structure and the model of the consciousness as a passive synthesis. The authors propose to recover estrangement as a primary experience and to concentrate on the concepts of subject and person's re-examination.


Assuntos
Despersonalização/psicologia , Ego , Humanos , Modelos Psicológicos
16.
J Mol Biol ; 314(5): 1067-75, 2001 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-11743723

RESUMO

Lrp is a global regulator of metabolism in Escherichia coli that helps cells respond to changes in environmental conditions. The action of Lrp as a transcriptional activator or repressor is sometimes affected by whether the medium contains exogenous leucine. The abundance of Lrp in cells is relatively high (about 15 microM in monomer), and given the relatively high Lrp binding affinity in vitro for specific binding sites (nanomolar apparent dissociation constants), the expectation is that all binding sites will be saturated with Lrp in vivo. Here we consider the fraction of the total Lrp in cells that is free and the fraction that is bound to DNA. Using minicell-producing strains, we measured the distribution of Lrp between cytoplasm and nucleoid in cells grown under different nutritional conditions and in cells in different phases of growth. In E. coli cells grown in minimal medium to mid-log phase, the ratio of free to DNA-bound Lrp was about 0.67. This ratio decreased about threefold when the cells were grown in minimal medium supplemented with leucine. Our results also confirmed the previous finding that growth rate regulates lrp expression by as much as three to fourfold. Growth rate-regulated lrp expression, along with changes in the extent of non-specific binding, influences the level of free Lrp in vivo over a 16-fold range. We propose that the net effect of these processes is to regulate the relative concentrations of free Lrp hexadecamer and leucine-bound octamer, leading to promoter selection in response to environmental conditions.


Assuntos
DNA Bacteriano/metabolismo , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Leucina/farmacologia , Fatores de Transcrição , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , DNA Bacteriano/genética , Proteínas de Ligação a DNA/química , Escherichia coli/citologia , Escherichia coli/crescimento & desenvolvimento , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Proteína Reguladora de Resposta a Leucina , Modelos Genéticos , Óperon/genética , Ligação Proteica/efeitos dos fármacos , Estrutura Quaternária de Proteína , Transporte Proteico/efeitos dos fármacos , Especificidade por Substrato
17.
J Mol Biol ; 312(4): 625-35, 2001 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-11575919

RESUMO

Lrp is a global regulatory protein in Escherichia coli that activates expression of more than a dozen operons and represses expression of another dozen. For some operons, exogenous leucine reduces the extent of Lrp action, for others it potentiates the effect of Lrp, and for yet other operons it has no effect. In an effort to understand how leucine affects Lrp-mediated expression, we examined Lrp self-association and the effect of leucine on self-association using light scattering, chemical cross-linking, and analytical ultracentrifugation. The following results were obtained. (i) Lrp self-associates to a hexadecamer and octamer with the predominant species being hexadecamer at microM concentrations. (ii) Lrp undergoes a leucine-induced dissociation of hexadecamer to octamer. (iii) A mutant Lrp lacking 11 amino acid residues at the C terminus does not form higher-order oligomers, suggesting that the C terminus is involved in subunit association. (iv) At nM concentrations, Lrp dissociates to a dimer. It is proposed that leucine regulates the equilibrium between Lrp oligomers and thus Lrp occupancy of sites within different operons, leading to diverse regulatory patterns.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Escherichia coli , Leucina/metabolismo , Fatores de Transcrição , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Reagentes de Ligações Cruzadas/metabolismo , Dimerização , Proteínas de Escherichia coli , Regulação Bacteriana da Expressão Gênica , Proteína Reguladora de Resposta a Leucina , Luz , Modelos Biológicos , Peso Molecular , Óperon/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Espalhamento de Radiação , Soluções , Termodinâmica , Ultracentrifugação
18.
Arch Esp Urol ; 54(5): 451-4, 2001 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-11494721

RESUMO

OBJECTIVE: To report a case of extrinsic ureteral obstruction arising from mucocele of the appendix and review the clinical, diagnostic and therapeutic aspects of this appendiceal pathology of interest in urology. METHODS: A 71-year-old female patient that had previously undergone radical gynecological surgery and postoperative radiotherapy presented with right lumbar pain. Patient evaluation by ultrasound, IVP and CT showed a pelvic mass causing right extrinsic ureteral obstruction. Release and reinsertion of the right ureter and appendectomy were performed. RESULTS: The anatomopathological study showed an appendiceal mucinous cystadenoma. The patient is asymptomatic after surgery. CONCLUSIONS: Appendiceal mucocele is a dilatation of the vermiform appendix due to collection of mucoid material that is frequently produced by a cystadenoma. The presenting feature is usually that of acute appendicitis. The definitive diagnosis is based on the anatomopathological findings. Treatment is by appendectomy for the benign tumors and by right hemicolectomy in a second stage procedure for malignant tumors. This appendiceal pathology should be taken into account in the differential diagnosis of right extrinsic ureteral obstruction.


Assuntos
Apêndice , Doenças do Ceco/complicações , Mucocele/complicações , Obstrução Ureteral/etiologia , Idoso , Feminino , Humanos
19.
J Bacteriol ; 183(13): 4004-11, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11395465

RESUMO

Lrp (leucine-responsive regulatory protein) plays a global regulatory role in Escherichia coli, affecting expression of dozens of operons. Numerous lrp-related genes have been identified in different bacteria and archaea, including asnC, an E. coli gene that was the first reported member of this family. Pairwise comparisons of amino acid sequences of the corresponding proteins shows an average sequence identity of only 29% for the vast majority of comparisons. By contrast, Lrp-related proteins from enteric bacteria show more than 97% amino acid identity. Is the global regulatory role associated with E. coli Lrp limited to enteric bacteria? To probe this question we investigated LrfB, an Lrp-related protein from Haemophilus influenzae that shares 75% sequence identity with E. coli Lrp (highest sequence identity among 42 sequences compared). A strain of H. influenzae having an lrfB null allele grew at the wild-type growth rate but with a filamentous morphology. A comparison of two-dimensional (2D) electrophoretic patterns of proteins from parent and mutant strains showed only two differences (comparable studies with lrp(+) and lrp E. coli strains by others showed 20 differences). The abundance of LrfB in H. influenzae, estimated by Western blotting experiments, was about 130 dimers per cell (compared to 3,000 dimers per E. coli cell). LrfB expressed in E. coli replaced Lrp as a repressor of the lrp gene but acted only to a limited extent as an activator of the ilvIH operon. Thus, although LrfB resembles Lrp sufficiently to perform some of its functions, its low abundance is consonant with a more local role in regulating but a few genes, a view consistent with the results of the 2D electrophoretic analysis. We speculate that an Lrp having a global regulatory role evolved to help enteric bacteria adapt to their ecological niches and that it is unlikely that Lrp-related proteins in other organisms have a broad regulatory function.


Assuntos
Acetolactato Sintase , Proteínas de Ligação a DNA/genética , Proteínas de Escherichia coli , Haemophilus influenzae/genética , Fatores de Transcrição , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Haemophilus influenzae/citologia , Proteína Reguladora de Resposta a Leucina , Dados de Sequência Molecular , Mutação , Fenótipo , Ligação Proteica , Homologia de Sequência de Aminoácidos
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