RESUMO
PURPOSE: It is unclear whether preoperative serum uric acid (SUA) elevation may play a role in the development of acute kidney injury (AKI) associated with cardiac surgery (CSA-AKI). We conducted a cohort study to evaluate the influence of preoperative hyperuricemia on AKI in patients at high risk for developing SC-AKI. DESIGN: Multicenter prospective international cohort study. SETTING: Fourteen university hospitals in Spain and the United Kingdom. PARTICIPANTS: We studied 261 consecutive patients at high risk of developing CSA-AKI, according to a Cleveland scoreâ¯≥â¯4 points, from July to December 2017. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: AKIN criteria were used for the definition of AKI. Multivariable logistic regression models and propensity score-matched pairwise analysis were used to determine the adjusted association between preoperative hyperuricemia (≥7â¯mg/dL) and AKI. Elevated preoperative AUS (≥7â¯mg/dL) was present in 190 patients (72.8%), whereas CSA-AKI occurred in 145 patients (55.5%). In multivariable logistic regression models, hyperuricemia was not associated with a significantly increased risk of AKI (adjusted Odds Ratio [OR]: 1.58; 95% confidence interval [CI]: 0.81-3; Pâ¯=â¯.17). In propensity score-matched analysis of 140 patients, the hyperuricemia group experienced similar adjusted odds of AKI (OR 1.05, 95%CI 0.93-1.19, Pâ¯=â¯.37). CONCLUSIONS: Hyperuricemia was not associated with an increased risk of AKI in this cohort of patients undergoing cardiac surgery at high risk of developing CSA-AKI.
Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Hiperuricemia , Complicações Pós-Operatórias , Ácido Úrico , Humanos , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/sangue , Estudos Prospectivos , Masculino , Feminino , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ácido Úrico/sangue , Idoso , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/sangue , Pessoa de Meia-Idade , Hiperuricemia/epidemiologia , Hiperuricemia/sangue , Fatores de Risco , Pontuação de PropensãoRESUMO
Rib fractures are common lesions in blunt chest trauma. Disregarding the severity of other high energy associated lesions, chest wall trauma characteristically causes intense pain, respiratory complications and long-term disability. Pain relief and chest wall function restoration are obtained by surgical stabilization of rib fractures. In nowdays still there is a considerable variability in surgical techniques and devices, as well as in their results and clinical indications. We report two cases of chest wall trauma and rib fractures repaired with osteosynthesis (Synthes® system MatrixRIB. Solothurn, Switzerland) and we discuss their new clinical indications and results.
Las fracturas costales son lesiones frecuentes en los traumatismos torácicos contusos. Sin contar aquellas lesiones asociadas con la alta absorción de energía, las fracturas costales causan característicamente dolor intenso, complicaciones respiratorias y ausentismo laboral significativo. Una de las estrategias terapéuticas es la estabilización quirúrgica del foco de fractura, la cual tiene múltiples ventajas teóricas como la disminución del dolor y la restauración de la función de la pared costal. Existen múltiples formas de fijación costal, pero su indicación, técnica quirúrgica y resultados son muy disímiles. Presentamos dos casos de reparación de pared torácica con material de osteosíntesis especialmente diseñado para este efecto (Synthes® MatrixRIB, Solothurn, Suiza), y se discuten sus alcances en las indicaciones y resultados clínicos.
Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Fixação Interna de Fraturas/métodos , Fraturas das Costelas/cirurgia , Titânio/uso terapêutico , Resultado do Tratamento , Parafusos Ósseos , Traumatismos Torácicos/cirurgiaRESUMO
OBJECTIVE: To analyze clinical records of cardiac surgery patients in an attempt to identify factors associated with mortality in the postoperative critical care units of the public health service hospitals in the Community of Valencia, Spain, in 2007. METHODS: Retrospective study of cases from January 1, 2007 to December 31, 2007. The charts of all patients who underwent cardiac surgery with or without extracorporeal circulation were reviewed. A data collection protocol was followed to obtain information on age, sex, body mass index (BMI), presurgical risk factors, type of surgery, duration of extracorporeal circulation, duration of ischemia, cause of death, and length of stay in the postoperative critical care unit. RESULTS: The study population consisted of 2113 patients at 5 public hospitals; 124 patients (70 men, 54 women) died. The mean (SD) age was 70 (9.43) years (range, 36-91 years). The mean BMI was 28.19 kg/m2 (maximum, 42 kg/m2). The mean Euroscore was 21.92 (maximum, 94.29). Hypertension was present as a preoperative risk factor in most patients (74.2%); dyslipidemia was present in 51.6%, diabetes mellitus in 38.7%, stroke in 73%, and renal failure in 2.4%. It was noteworthy was that the group who underwent coronary revascularization had the highest mortality rate (nearly 35% of the 124 patients). The next highest mortality rate (19.4%) was in patients who had combined procedures (valve repair or substitution plus coronary revascularization). Mortality was 18.5% in the group undergoing aortic valve surgery and 11.3% in those undergoing mitral valve surgery. The mean duration of extracorporeal circulation was 148.63 minutes. The mean duration of myocardial ischemia was 94.91 minutes. The most frequent cause of death was cardiogenic shock (54.8%). This was followed by distributive shock (29.8%) and hemorrhagic shock (8.9%). The mean length of stay in the postoperative critical care unit was 13.6 days. Overall mortality was 5.87%. CONCLUSIONS: The highest mortality rate among cardiac surgery patients in postoperative critical care units in hospitals in the Community of Valencia in 2007 was in patients who underwent coronary revascularization. The most prevalent preoperative risk factor was hypertension. Cardiogenic shock and distributive shock were the most frequent causes of death in these patients. A system for classifying risk is needed in order to predict mortality in critical care units and improve perioperative care.
Assuntos
Procedimentos Cirúrgicos Cardíacos/mortalidade , Mortalidade Hospitalar , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Comorbidade , Diabetes Mellitus/epidemiologia , Circulação Extracorpórea/efeitos adversos , Feminino , Humanos , Hipertensão/epidemiologia , Nefropatias/epidemiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Estudos Retrospectivos , Fatores de Risco , Choque/etiologia , Choque/mortalidade , Espanha/epidemiologiaRESUMO
We present coarse-grained molecular dynamics simulations of poly(ethylene-alt-propylene) (PEP) melts, ranging in chain length from about N(e) (the entanglement length) to N=6N(e). The coarse-grained parameters, potential of mean force and bare friction, were determined from fully atomistic molecular dynamics simulations carried out on a PEP cell containing 12 chains of 80 monomers each and subjected to periodic boundary conditions. These atomistic simulations were previously validated by means of extensive neutron scattering measurements. Uncrossability constrains were also introduced in the coarse-grained model to prevent unphysical bond crossing. The coarse-grained simulations were carried out at 492 K and focus on chain dynamics. The results obtained were analyzed in terms of Rouse coordinates and Rouse correlators. We observe deviations from Rouse behavior for all chain lengths investigated, even when the chain stiffness is incorporated in the Rouse model. These deviations become more important as the chain length increases. The general scenario emerging from the results obtained is that the deviations from Rouse-like behavior are due to correlations among the forces acting upon a chain bead, which seem to be related with the constraint of uncrossability among the chains. As consequence, nonexponentiality of the Rouse correlators and mode- and time-dependent friction are observed. It seems that, in the molecular weight explored, these effects still give not raise to reptation behavior but to a crossover regime between Rouse and reptation. On the other hand, the results obtained are in qualitative agreement with those expected from the so-called generalized Rouse models, based on memory function formalisms.
Assuntos
Alcenos/química , Polietileno/química , Simulação por Computador , Simulação de Dinâmica MolecularRESUMO
Oleoylethanolamide (OEA), agonist of nuclear PPAR-alpha receptors and antagonist of vanilloid TRPV1 receptors, has been reported to show cytoprotective properties. In this study, OEA-induced neuroprotection has been tested in vitro and in vivo models of 6-OHDA-induced degeneration of substantia nigra dopamine neurons. First, PPAR-alpha receptors were confirmed to be located in the nigrostriatal circuit, these receptors being expressed by dopamine neurons of the substantia nigra, and intrinsic neurons and fibers bundles of the dorsal striatum. In the substantia nigra, their location was confined to the ventral tier. The in vitro study showed that 1 microM OEA exerted a significantly neuroprotective effect on cultured nigral dopamine neurons, effects following U-shaped dose-response curves. Regarding the in vivo study, rats were locally injected with OEA into the right striatum and vehicle into the left striatum 30 min before 6-OHDA-induced striatal lesion. In the short term, signals of heme oxygenase-1 (oxidation marker, 24 and 48 h post-lesion) and OX6 (reactive microglia marker, 96 h post-lesion) were found to be significantly less intense in the striatum pretreated with 5 microM OEA. In the long term (1 month), reduction in striatal TH and synaptophysin was less intense whether the right striatum was pretreated with 5 microM OEA, and nigral TH+ neuron death was significantly reduced after pretreatment with 1 and 5 microM OEA. In vivo effects also followed U-shaped dose-response curves. In conclusion, OEA shows U-shaped partial and dose-dependent neuroprotective properties both in vitro and in vivo models of substantia nigra dopamine neuron degeneration. The occurrence of U-shaped dose-response relationships normally suggests toxicity due to high drug concentration or that opposing intracellular pathways are activated by different OEA doses.
Assuntos
Dopamina/metabolismo , Degeneração Neural/prevenção & controle , Fármacos Neuroprotetores/uso terapêutico , Ácidos Oleicos/uso terapêutico , Substância Negra/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Endocanabinoides , Masculino , Degeneração Neural/induzido quimicamente , Neurônios/metabolismo , Oxidopamina , PPAR alfa/metabolismo , Ratos , Ratos Wistar , Substância Negra/efeitos dos fármacos , Sinaptofisina/metabolismoAssuntos
Tumor Glômico , Antro Pilórico , Neoplasias Gástricas , Adulto , Gastrectomia , Gastroscopia , Tumor Glômico/diagnóstico , Tumor Glômico/patologia , Tumor Glômico/cirurgia , Humanos , Laparoscopia , Masculino , Antro Pilórico/patologia , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgiaRESUMO
Objetivo: El objetivo primario del estudio es evaluar el impacto del índice pronóstico de Van Nuys (VNPI) en la recurrencia del carcinoma ductal in situ de mama (CDIS). Entre los objetivos secundarios se incluye la valoración de otros parámetros histológicos: el tamaño, el grado nuclear, la necrosis, la supervivencia libre de enfermedad y la supervivencia global. Método: Se analizaron los casos con diagnóstico de CDIS entre enero de 1995 a diciembre de 2000, de la base de datos de la Unidad de Mama del Hospital Universitario La Paz, Madrid, España. Se han recogido los hallazgos mamográficos, histológicos, así como la evolución de las pacientes. Resultados: Se diagnosticaron 95 CDIS en el periodo estudiado, de los que solo se incluyeron 79 casos en el análisis estadístico. El CDIS representa el 7,1 por ciento de todos los cánceres de mama en nuestro centro. La presencia de microcalcificaciones en la mamografía de cribado es el hallazgo diagnóstico mas frecuente. Ninguna de las variables clínicas analizadas se asoció a una mayor tasa de recaídas. Se asoció significativamente (p<0,05) a una mayor tasa de recurrencias el tamaño tumoral, el alto grado y la necrosis, así como el VNPI. Conclusiones: El CDIS tiene un comportamiento muy variable y ha de considerarse como entidades aisladas más que como una única enfermedad. Los parámetros biológicos e histológicos, principalmente el VNPI, podrían ayudara individualizar el tratamiento.
Objective: The primary endpoint of our study was to evaluate the impact of Van Nuys Prognostic index (VNPI) on recurrence of the breast ductal carcinoma in situ (DCIS). Secondary endpoints included other histologic features: size, nuclear grade, necrosis and architectural pattern, disease-free survival and ove-rail survival. Methods: Database of the breast unit was searched for patients with DCIS diagnose between January 1995 and December 2000. Clinical data, mammographic findings, pathological features, outcome and prognosis were studied. Results: Ninty five DCIS were detected at our center between 1995-2000, but only 79 patients were included in the statistical analysis. The incidence was 7.1 percent over the total number of breast cancers. Diagnose was made by a screening mammography in the majority of cases, and presence of microcalcifications was the most frequent mammographic finding. None of the clinical variables was associated to bigger rates of relapse. Tumour size, high grade and necrosis and VNPI had a significant association with recurrence. Conclusions: Disease outcomes are very diverse, and it is necessary to consider DCIS as different entities, more than as an isolated disease. Biologic and histological factors, mainly VNPI, allow to stratify patients according to their risk and help to individualize treatment.
Assuntos
Humanos , Feminino , Carcinoma Ductal de Mama/patologia , Carcinoma in Situ/patologia , Neoplasias da Mama/patologia , Índice de Gravidade de Doença , Carcinoma Ductal de Mama/mortalidade , Carcinoma in Situ/mortalidade , Intervalo Livre de Doença , Necrose , Recidiva Local de Neoplasia , Neoplasias da Mama/mortalidade , Prognóstico , Estudos Retrospectivos , Espanha , Taxa de SobrevidaRESUMO
We report a 45 years-old woman operated in 2003 for a stage IV uterine leiomyosarcoma with lung metastases. Pulmonary metastases were surgically excised in 2003, 2005 and finally in July, 2006. Since then, the patient is in good conditions. There is evidence that resection of pulmonary metastases of gynecologic cancers, when the primary tumor is controlled, significantly prolongs survival.
Assuntos
Leiomiossarcoma/secundário , Neoplasias Pulmonares/secundário , Neoplasias Uterinas/patologia , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reoperação , Tomografia Computadorizada por Raios XRESUMO
Pancoast tumors represent a rare presentation of lung cancer. Their particular location delays diagnosis and makes resection difficult. Nevertheless recent advances in surgical techniques and multi-modality therapy (chemo-radiation followed by surgery) had increased resection rates and achieved long term survival. We present the case of a 62-year-old woman with an extensive Pancoast tumor and a synchronous hypofisiary lesion. We carried out an exhaustive staging workout determining that the infratentorial lesion was a hypofisiary adenoma. She underwent induction chemo-radiotherapy and posterior surgery. A complete resection was possible with prolonged survival and minimal functional disability. We present the evolution in management of Pancoast tumors and our approach to patients with suspicious metastases in potentially resectable tumors.
Los tumores de Pancoast representan una presentación poco frecuente de los cánceres pulmonares. Su particular localización retrasa el diagnóstico y dificulta su resección. En los últimos años se han realizado importantes avances en las técnicas quirúrgicas y se ha consolidado la terapia tri-modal en el manejo de estos pacientes mejorando su sobrevida. Presentamos el caso de una mujer de 62 años con un extenso tumor de Pancoast y una lesión sincrónica hipofísiaria. Un exhaustivo estudio de diseminación permitió determinar que esta lesión era un adenoma hipofisiario. Se realizó quimio y radioterapia de inducción y posteriormente una resección completa del tumor, con una sobrevida prolongada sin secuelas funcionales. Se presenta la evolución del manejo de estos tumores y nuestra conducta en el enfrentamiento de posibles metástasis en tumores potencialmente curables.
Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/tratamento farmacológico , Síndrome de Pancoast/cirurgia , Síndrome de Pancoast/tratamento farmacológico , Terapia Combinada , Neoplasias Hipofisárias/secundário , Neoplasias Pulmonares/patologia , Síndrome de Pancoast/patologia , Resultado do TratamentoRESUMO
We report a 45 years-old woman operated in 2003 for a stage IV uterine leiomyosarcoma with lung metastases. Pulmonary metastases were surgically excised in 2003, 2005 and finally in July, 2006. Since then, the patient is in good conditions. There is evidence that resection of pulmonary metastases of gynecologic cancers, when the primary tumor is controlled, significantly prolongs survival.
Assuntos
Feminino , Humanos , Pessoa de Meia-Idade , Leiomiossarcoma/secundário , Neoplasias Pulmonares/secundário , Neoplasias Uterinas/patologia , Neoplasias Pulmonares/cirurgia , Estadiamento de Neoplasias , Reoperação , Tomografia Computadorizada por Raios XRESUMO
The fluorescence spectroscopy technique has been tested as regards its ability to differentiate between refined hazelnut and olive oils. Classification of these oils based on their excitation-emission fluorescence spectra data (spectral range 300-500 nm of the excitation spectra at lambdaem=655 and spectral range 650-900 of the emission spectra at lambdaex=50 nm) was performed using principal component analysis and artificial neural networks. Both methods provided good discrimination between the refined hazelnut and olive oils. The results have also pointed out the possibilities of a spectrofluorimetric method joined to multivariate analysis, to differentiate refined oils, and even to detect the presence of refined hazelnut oils in refined olive oils at percentages higher than 9%.
Assuntos
Corylus/química , Contaminação de Alimentos/análise , Óleos de Plantas/análise , Espectrometria de Fluorescência , Análise de Variância , Azeite de Oliva , Óleos de Plantas/classificaçãoRESUMO
The effects of UV radiation on the chemical and sensory characteristics of virgin olive oils (cv. Arbequina and Picual) were assessed. Even small doses of UV radiation induced oxidation of the virgin olive oil samples. Total phenols and fatty acids contents decreased during the process as well as the intensity of the bitter and fruity sensory attributes, while the intensity of the rancid sensory attribute notably increased. Acetaldehyde, 2-butenal, 2-pentenal, octane, octanal, hexanal, nonanal, and 2-decenal were the volatile compounds most affected, showing an important increase during the irradiation process. Nonanal, hexanal, and pentanal showed high correlation with the rancid sensory attribute (90%, 86%, and 86%, respectively). 2-Decenal and nonanal concentrations allowed us to predict the alteration level of the samples by mean of multiple Ridge regression.
Assuntos
Óleos de Plantas/efeitos da radiação , Raios Ultravioleta , Cromatografia Gasosa , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Azeite de Oliva , Oxirredução , Fenóis/análise , Óleos de Plantas/química , Análise de Regressão , Olfato , Paladar , VolatilizaçãoRESUMO
We report a 67 years old male with a history of pulmonary tuberculosis at the age of 15, that consults for malaise, weight loss and productive cough. Chest X ray examination showed a left pleural effusion. A pleural tap obtained a sterile exudate. A thorax CAT scan showed a proliferating mass in the splenic angle of the colon, with left lung and diaphragmatic invasion. Endoscopic biopsies confirmed the diagnosis of adenocarcinoma. The patient underwent a subtotal colectomy with partial excision of diaphragm and left lung. The pathological report showed a mucosecretory adenocarcinoma, infiltrating the pericolonic adipose tissue without adjacent organ infiltration and a chronic inflammatory process involving colonic serosa, diaphragm pleura, and lung. Adjuvant chemotherapy was indicated and the patient is asymptomatic and without evidences of tumor recurrence after a 24 months follow up (Rev Méd Chile 2004; 132: 985-88).
Assuntos
Masculino , Humanos , Idoso , Neoplasias Colorretais , Adenocarcinoma Mucinoso/cirurgia , Adenocarcinoma Mucinoso/patologia , Neoplasias Musculares , SeguimentosRESUMO
Pig liver oligosaccharyltransferase (OST) is a heterooligomeric protein complex responsible for the co-translational transfer of GlcNAc2-Man9-Glc3 from Dol-PP onto specific asparagine residues in the nascent polypeptide. OST48, one of the catalytic subunits in this complex, exerts a typical type I membrane topology, containing a large luminal domain, a hydrophobic transmembrane domain and a short cytosolic peptide tail. Because OST48 is found within the endoplasmic reticulum (ER) when overexpressed in COS-1 cells, we carried out experiments to identify structural signals potentially capable of directing ER-targeting, using OST48 mutants and hybrid proteins consisting of individual OST48 domains and Man9-mannosidase. Immunofluorescence microscopy showed that OST48 mutants in which the C-terminal lysine-3 or lysine-5, but not lysine-7, had been replaced by leucine (OST48AK) could be detected on the cell surface. This indicates that these two lysine residues are sufficient for conferring ER-residency on OST48. The double-lysine motif operates only when exposed cytosolically, where it acts as a relocation signal rather than causing retention. OST48AK-3, when co-expressed in COS-1 cells together with myc-tagged ribophorin 1, was quantitatively retained in the ER. By contrast, co-expression in the presence of ribophorin I resulted in no reduction of cell surface fluorescence for the OMOdeltaK-5 chimera containing the cytosolic and transmembrane domain of OST48 attached to the C-terminus of the Man9-mannosidase luminal domain. Thus ER-localisation of OST48 is probably brought about by complex formation with ribophorin I and this most likely involves the luminal domains of both proteins. Consequently, the double-lysine motif in the cytosolic domain of OST48 is unlikely to have a primary function except being involved in re-capture of molecules which have escaped from the ER.
Assuntos
Retículo Endoplasmático/enzimologia , Hexosiltransferases , Fígado/enzimologia , Suínos/metabolismo , Transferases/metabolismo , Motivos de Aminoácidos , Animais , Western Blotting , Células COS , Sequência de Carboidratos , Chlorocebus aethiops , Citosol/enzimologia , Retículo Endoplasmático/fisiologia , Fígado/ultraestrutura , Proteínas de Membrana/metabolismo , Microscopia de Fluorescência , Mutagênese Sítio-Dirigida , Estrutura Terciária de Proteína , Transdução de Sinais/fisiologia , Transfecção , Transferases/genéticaRESUMO
A sensor array of 32 conducting polymer sensors has been used to detect the rancid defect in virgin olive oils. A training set, composed of admixtures of a Portuguese virgin olive oil with different percentages (0-100%) of a rancid standard oil, was used for the selection of the best sensors classifying correctly the samples. Information on volatile compounds responsible for rancidity and the sensory evaluation of samples by assessors were used for explaining the mathematical selection of sensors. A tentative calibration, using unsupervised procedures (PCA and MDS) and a nonlinear regression, was carried out, with the training set, and later confirmed with a test set with which rancid commercial samples of different varieties were used to spike a Greek extra virgin olive oil at low levels of rancidity (0.5-6%).
Assuntos
Gorduras Insaturadas na Dieta/análise , Odorantes/análise , Óleos de Plantas/análise , Gorduras Insaturadas na Dieta/normas , Eletrônica , Conservação de Alimentos , Humanos , Azeite de Oliva , Óleos de Plantas/normas , Padrões de Referência , VolatilizaçãoRESUMO
The aim of this work was the characterization of the glycoconjugates of the premeiotic spermatogenetic cells of the testis of an urodele amphibian, Pleurodeles waltl, by means of lectins in combination with several chemical and enzymatic procedures, in order to establish the distribution of N- and O-linked oligosaccharides in these cells. In the cytoplasm of the primordial germ cells, primary and secondary spermatogonia and primary spermatocytes, a granular structure can be observed close to the nucleus. These granules contain four types of sugar chains according to their appearance during the differentiation process: 1. some oligosaccharides that are identified in all the four cell types above mentioned, which include N-linked oligosaccharides with Fuc, Gal beta1,4GlcNAc and Neu5Ac alpha2,3Gal beta1,4GlcNAc and O-linked oligosaccharides with Gal beta1,4GlcNAc and Neu5Ac alpha2,3Gal beta1,4GlcNAc; 2. other glycan chains that are not present in the primary spermatocytes (N-linked oligosaccharides with DBA-positive GalNAc, GlcNAc, and a slight amount of Neu5Ac alpha2,6Gal/GalNAc and O-linked oligosaccharides with WGA-positive GlcNAc); 3. the sugar chains that are not in the earliest step of spermatogenesis (formed by both N-linked and O-linked oligosaccharides with Glc); and 4. other that appear at the earliest and latest stages, but not in the intermediate ones, (N-linked oligosaccharides with Man and O-linked oligosaccharides with SBA- and HPA-positive GalNAc and PNA-positive Gal beta1,3GalNAc). This structure could be related with the Drosophila spectrosome and fusome, unusual cytoplasmic organelles implicated in cystic germ cell development. Data from the present work, as compared with those from mammals and other vertebrates, suggest that, although no dramatic changes in the glycosylation pattern are observed, some cell glycoconjugates are modified in a predetermined way during the early steps of the spermatogenetic differentiation process.
Assuntos
Células Germinativas/metabolismo , Meiose/fisiologia , Oligossacarídeos/metabolismo , Pleurodeles/metabolismo , Polissacarídeos/metabolismo , Espermatogênese/fisiologia , Testículo/metabolismo , Acetilgalactosamina/metabolismo , Acetilglucosamina/metabolismo , Animais , Fucose/metabolismo , Galactose/metabolismo , Células Germinativas/citologia , Lectinas/farmacologia , Masculino , Manose/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Nitrogênio/metabolismo , Oxigênio/metabolismo , Pleurodeles/anatomia & histologia , Espermatócitos/citologia , Espermatócitos/metabolismo , Espermatogônias/citologia , Espermatogônias/metabolismo , Testículo/citologiaRESUMO
Oligosaccharyltransferase (OST) is an oligomeric protein complex which catalyses the transfer en bloc of Glc(3)-Man(9)-GlcNAc(2) from Dol-PP to specific asparagine residues in the nascent polypeptide chain. In order to study the function of the pig enzyme subunits, we have cloned OST48, ribophorin I and ribophorin II and characterized these proteins after in vitro translation as well as after expression in COS-1 cells. The individual full-length cDNAs contained open reading frames (ORFs) encoding polypeptides with calculated molecular masses of approximately 48.9 kDa (OST48), approximately 68.7 kDa (ribophorin I) and approximately 69.3kDa (ribophorin II), respectively. A Kyte and Doolittle hydrophobicity analysis revealed that OST48, ribophorin I and ribophorin II possess a type I membrane topology with the bulk of their polypeptide chains directed towards the ER-lumen. In contrast to OST48, ribophorin I and II contain, respectively, three or two potential N-glycosylation sites of the Asn-Xaa-Thr/Ser type; only one is found to function as the acceptor site in each protein. Transfection of COS-1 cells with vector constructs encoding either OST48, ribophorin I, or a ribophorin I variant tagged with a myc-peptide sequence, resulted in the over-expression of polypeptides whose molecular masses were similar to those calculated from the respective cDNA ORFs. None of these three polypeptides, or ribophorin II, were found to display OST activity when over-expressed alone. By contrast, a modest but reproducible approximately 25% increase of activity was observed when OST48 together with ribophorin I, or OST48 and myc-tagged ribophorin I, were co-expressed, indicating that these two subunits are probably responsible for the catalytic activity in the hetero-oligomeric OST complex. The only modest over-expression of transferase activity suggests that either the dimeric enzyme complex is catalytically unstable, or that the OST48 and ribophorin I polypeptides are unable to fold properly when other subunit components of the hetero-oligomeric OST complex are lacking. OST48 as well as ribophorin I are expressed in COS-1 cells as ER-resident proteins. Whereas OST48 carries a double-lysine motif in the -3/-5 position of its cytosolic C-terminal domain, ribophorin I does not contain recognizable ER-retention information. Replacing the lysine residue in the -3 position by leucine resulted in plasma membrane expression of the OST48-Leu polypeptide, indicating that this sequence motif may be able to influence OST48 localisation. No cell surface staining was observed when OST48-Leu was co-expressed with ribophorin I. This suggests that localisation of OST48 in the ER is mediated by interaction with ribophorin I rather than by the double-lysine motif.
Assuntos
Hexosiltransferases , Fígado/enzimologia , Proteínas de Membrana/genética , Transferases/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Células COS , Domínio Catalítico , Clonagem Molecular , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Proteínas Recombinantes/metabolismo , Suínos , Transferases/metabolismoRESUMO
Phenolic and orthodiphenolic compounds together with carotenoids, tocopherols, pigments, and fatty acids were tested for their antioxidant effect in 79 samples of virgin olive oils cv. Picual and Hojiblanca. A linear regression based on the oleic/linoleic ratio and the contents of phenols and tocopherols showed a good correlation (adjusted-R(2) = 0.91) with the stability measured by Rancimat, later verified with an external text set (adjusted-R(2) = 0.95). A tentative study on the percentage contribution of each chemical variable to stability is discussed. The contribution of phenolic and orthodiphenolic compounds was around 51%, the composition of fatty acids 24%, and in less percentage alpha-tocopherol, carotenoids, and chlorophylls. No effect, or very little, was shown by beta- and gamma-tocopherols.
Assuntos
Antioxidantes/análise , Óleos de Plantas/química , Carotenoides/análise , Clorofila/análise , Ácidos Graxos/análise , Conservação de Alimentos , Humanos , Azeite de Oliva , Fenóis/análise , Vitamina E/análiseRESUMO
A clinical case is presented of a 37 year old patient with acute myelocytic leukemia who conceived while in therapy. The pregnancy was controlled in our department in association with the Hematology Department. A cesarean section was performed in the 37th week of gestation, resulting in a healthy newborn. A review of literature is presented, analyzing the association between these two conditions, as well as repercussion on the mother and infant and the recommended obstetric management.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Leucemia Mielomonocítica Aguda/terapia , Complicações Neoplásicas na Gravidez/terapia , Adulto , Antimetabólitos Antineoplásicos/administração & dosagem , Transfusão de Componentes Sanguíneos , Chile , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Feminino , Humanos , Recém-Nascido , Leucemia Mielomonocítica Aguda/diagnóstico , Masculino , Gravidez , Indução de RemissãoRESUMO
La pleuroneumonía complicada con empiema tabicada en el niño presenta una evolución tórpida con prolongados períodos de hospitalización. Se ha destacado el rol de la toracotomía y aseo quirúrgico en estos pacientes. Presentamos nuestra experiencia en 5 niños con empiema pleural tabicado, cuya evolución fue tórpida tratados medicamente con antibióticos y drenajes pleurales. En dos casos el cultivo de líquido pleural fue positivo para neumococo y en un caso para hemophilus influenzae B-lactamasa (+). La ultrasonografía torácica demostró derrame pleural tabicado con múltiples loculaciones en todos los casos. Todos ellos fueron tratados quirúrgicamente con toracotomía y aseo quirúrgico entre el cuarto y octavo días de hospitalización, extrayendo líquido pleural citrino y gran cantidad de fibrina. La evolución postoperatoria fue satisfactoria en 4 casos. Un niño presentó como complicación una fístula broncopleural que requirió una segunda intervención quirúrgica. Se destaca la ultrasonografía torácica en el diagnóstico de empiema tabicado y el rol de la toracotomía con aseo quirúrgico en el tratamiento de esta complicación ante el fracaso de la terapia médica convencional