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1.
Sci Rep ; 13(1): 14324, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37652944

RESUMO

A new two-step densification method for wooden materials entitled hot isostatic pressing (HIP) is proposed. This method has the advantage over previous densification methods that can achieved almost the full densification of wood, reaching values up to 1.47 kg/m3, which exceeds any value ever reported for a hardwood species. Furthermore, it can preserve about 35% of the original volume, in comparison to other methods which typically can preserve only 20% of the volume. Although not tested in this investigation, in principle, the HIP method should be capable of densifying any shape of wood including circular and tubular cross sections because the main densification mechanism is based on gas pressure that is equally exerted in the entire surface, rather than localized mechanical compression, which can only be effective with rectangular cross sections. In the first stage of the two-step proposed method, the compressive strength of the anatomical wood structure is reduced by delignification, and, in the second, a full densification is achieved by hot isostatic pressing under argon atmosphere. Three tropical hardwood species with distinct anatomical characteristics and properties were used to test the method. The HIP-densified wood's microstructural, chemical, physical, and mechanical properties were assessed. Apart from the high densification values and volume preservation, the results indicate that proposed method was effective for all the tested species, showing homogenous density patterns, stable densification without noticeable shape recovery, and enhanced mechanical properties. Future research should test the HIP method in softwoods and consider the ring orientation in order to enhance the control of the densified geometry.

2.
Forensic Sci Int ; 328: 111054, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34666305

RESUMO

Capillary diffraction or microdiffraction are standard techniques for characterizing small samples when only a few milligrams are available. On the other hand, we have typical grazing incidence diffraction or different variations of grazing incidence (GI) diffraction used, such as in-plane grazing incidence (IP-GI) or GI using a micro focusing source, to study thin films. However, when few powder micrograms are available, the characterization task is complicated. In the present work, few micrograms of typical forensic samples are analyzed using standard Bragg-Brentano, X-ray powder diffraction geometry, and grazing incidence X-ray micro-diffraction (GIµXRD). Samples include soils, cosmetic eyeshadows, two different pyrotechnic materials, and a highly explosive mixture contained at primer cup of ammunition. The analysis was carried out from 1 to 5 degrees of the incident parallel beam with a shaking sample. Depending on the fixed incident angle, different small regions of the diffraction patterns showed an improvement in the intensity of the peaks with respect to the conventional Bragg-Brentano configuration. However, 3-5 degrees of the fixed incident beam showed the best results. This new data acquisition technique, based on the combination of two known diffraction methods, could be a powerful tool for studying samples outside of forensic sciences such as nanomaterials, medicine, or any other field where the sample quantity is extremely small, also, without the need to transport evidence and travel to external facilities with higher analytical performance such as synchrotron radiation installations or other large experimental facilities.

3.
Rev. mex. ing. bioméd ; 40(3): e201926, sep.-dic. 2019. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1127062

RESUMO

Resumen En estudios previos se ha demostrado que la endotoxemia inducida por lipopolisacárido (LPS) produce un desacoplamiento cardiorrespiratorio (CRP) debido a los efectos fisiológicos de la inflamación sistémica. Adicionalmente se sabe que la oxitocina tiene efectos antiinflamatorios y propiedades cardioprotectoras; sin embargo, se desconoce si ésta modifica el acoplamiento CRP. El objetivo del presente estudio fue comparar diferentes métodos matemáticos lineales y no lineales para la detección del desacoplamiento cardiorrespiratorio entre series de tiempo cardiacas y respiratorias. Se estudiaron series de tiempo R-R obtenidas de electrocardiogramas de grupos de roedores macho a los cuales se les administró solución salina o vehículo (V); lipopolisacárido (LPS); oxitocina (O) y LPS + oxitocina (LPS+Ox). Las series R-R y respiratorias derivadas del electrocardiograma (EDR) se analizaron en conjunto para cuantificar su grado de acoplamiento a través de las técnicas de correlación cruzada; entropía muestral cruzada; entropía condicional; información mutua; e información mutua de Rényi para los cuatro grupos. Se observó que la oxitocina no parece favorecer el acoplamiento CRP durante la endotoxemia inducida por LPS. Finalmente, se encontró que la entropía muestral cruzada y la entropía condicional presentaron las mayores diferencias estadísticas para identificar el desacoplamiento CRP producido por el LPS.


Abstract Previous studies have shown that LPS-induced endotoxemia causes a cardiorespiratory (CRP) uncoupling owing to the physiological effects of systemic inflammation. Also, it is known that oxytocin has anti-inflammatory effects and cardioprotective properties; however, it is unknown whether it can modify the CRP coupling. This study aimed to compare different linear and nonlinear mathematics methods for the detection of cardiorespiratory uncoupling between cardiac and respiratory time series. The R-R time series of electrocardiograms of male rodents that were administered with saline solution (V); lipopolysaccharide (LPS); oxytocin (O) and LPS + oxytocin (LPS + Ox) were studied. We tested the R-R and respiratory series derived from the electrocardiogram (EDR) for the four groups to quantify the degree of coupling with cross-correlation; cross sample entropy; conditional entropy; mutual information; and Rényi's mutual information. We found that oxytocin does not seem to favor the CRP coupling during endotoxemia induced by LPS. Finally, we observed that the cross-sample entropy and the conditional entropy presented the highest statistical differences to identify the CRP uncoupling produced by LPS.

4.
Curr Top Med Chem ; 18(14): 1188-1202, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30117393

RESUMO

Bacterial resistance is a growing problem worldwide and is estimated that deaths by infectious diseases associated with resistant pathogens will generate 10 million deaths per year in 2050. This problem becomes more serious due to the low level of research and development of new drugs, which has fallen drastically in the last 40 years. For example, in the last decade of a total of 293 new drugs approved by the FDA, only 9 corresponded to antimicrobial drugs and none constituted a new structural class. The majority of the molecules in the clinical phase II or III, coming from modifications of drugs in clinical use, this strategy makes easier the bacterial susceptibility to generate resistance through the mechanisms expressed for their drug predecessors. Under this scenario, it is urgent to generate the most novel strategies for the development of antibacterial compounds with new targets or mechanism of action, without a structural relationship with the antibiotic drugs predecessors. Under this look, the present review addresses the development of the latest antibacterial drugs in clinical phases II and III, analyzing the design strategies by which these new molecules were obtained and the structure-activity relationship of these new families of antibiotics, in order to define the state of the vanguard antibacterial drugs in the post-antibiotic era.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Animais , Humanos , Relação Estrutura-Atividade
5.
Rev. pediatr. electrón ; 15(2): 2-10, ago. 2018. tab
Artigo em Espanhol | LILACS | ID: biblio-994498

RESUMO

Introducción: Existen varias curaciones para quemaduras. La sulfadiazina de plata se ha usado por años pero las membranas microporosas son cada vez más preferidas. Objetivos: Comparar la eficiencia de las membrana microporosa (Telfa Clear®) versus sulfadiazina de plata (Platsul®) en menores de 15 años hospitalizados por quemadura. Pacientes y Métodos: Estudio de cohorte retrospectivo de 87 pacientes, dividido en 2 grupos comparables en extensión y profundidad de la quemadura, edad y sexo. Durante enero a diciembre 2007 se curaron 52 pacientes con Platsul® y desde enero a octubre 2008 se curaron 35 con Telfa Clear®. Se evalúa tiempos y extensión de reepitelización, porcentaje de injertos, costos, días de hospitalización, número de curaciones, complicaciones, almacenamiento-estabilidad y costos. Estadística no paramétrica para el análisis univariado y regresión logística multivariado en Stata 11.2. Resultados: Los pacientes curados con Platsul® se injertaron más tardíamente y presentan más curaciones. Platsul® es peor evaluado por su almacenamiento-estabilidad y mayores costos. No hay diferencia en la incidencia de infección. Conclusiones: Ambas Técnicas son eficientes en permitir reepitelización, pero Platsul® puede demorar el injerto. La Telfa Clear® es mejor evaluado por el equipo de salud en cuanto a almacenamiento y estabilidad. El menor costo de Telfa Clear® es una ventaja.


Introduction: There are several dressings for burns. Silver sulfadiazine has been used for years but microporous membranes are increasingly preferred. Objectives: To compare the efficiency of microporous membrane (Telfa Clear®) versus silver sulfadiazine (Platsul®) in children younger than 15 years old hospitalized for burns. Patients and Methodology: Retrospective cohort study of 87 patients, divided into 2 comparable groups in extent and depth of the burn, age and sex. During January to December 2007, in 52 patients Platsul® were use and in 35 patients Telfa Clear® were use from January to October 2008. The time and extent of re-epithelialization, percentage of grafts, costs, length of stay, number of dressing change, complications, storage-stability and costs are evaluated. Non-parametric statistics were used for univariate analysis and logistic regression for multivariate analysis en Stata 11.2. Results: Platsul® was associate to a later graft and had a greater number of dressing changes. Platsul® is worst rated for its storage-stability and higher costs. No difference in infection rate was observed. Conclusions: Both techniques are efficient in allowing re-epithelialization, but burns treated with Platsul® were grafted later than when Telfa Clear® was used. Telfa Clear® is best evaluated by the health team in terms of storage and stability. The cost of Telfa Clear® is presented as an advantage.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Sulfadiazina de Prata/uso terapêutico , Bandagens , Queimaduras/terapia , Anti-Infecciosos Locais/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Reepitelização
6.
PLoS One ; 12(10): e0185652, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29020065

RESUMO

While 2-amino-4-(4-chlorophenyl)thiazole (AT) drug and thiazole derivatives have several biological applications, these compounds present some drawbacks, such as low aqueous solubility and instability. A new complex of ßCD-AT has been synthesized to increase AT solubility and has been used as a substrate for the deposit of solid-state AuNPs via magnetron sputtering, thus forming the ßCD-AT-AuNPs ternary system, which is stable in solution. Complex formation has been confirmed through powder X-ray diffraction and 1D and 2D nuclear magnetic resonance. Importantly, the amine and sulfide groups of AT remained exposed and can interact with the surfaces of the AuNPs. The complex association constant (970 M-1) has been determined using phase solubility analysis. AuNPs formation (32 nm average diameter) has been studied by UV-Visible spectroscopy, transmission/scanning electron microscopy and energy-dispersive X-ray analysis. The in vitro permeability assays show that effective permeability of AT increased using ßCD. In contrast, the ternary system did not have the capacity to diffuse through the membrane. Nevertheless, the antibacterial assays have demonstrated that AT is transferred from ßCD-AT-AuNPs, being available to exert its antibacterial activity. In conclusion, this novel ßCD-AT-AuNPs ternary system is a promising alternative to improve the delivery of AT drugs in therapy.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Preparações Farmacêuticas/metabolismo , Tiazóis/química , beta-Ciclodextrinas/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Transporte Biológico , Cristalização , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Permeabilidade , Pós , Espectroscopia de Prótons por Ressonância Magnética , Solubilidade , Soluções , Espectrometria por Raios X , Tiazóis/farmacologia , Difração de Raios X , beta-Ciclodextrinas/farmacologia
7.
Arch Virol ; 161(3): 665-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26611910

RESUMO

Zika virus (ZIKV) is an emerging mosquito-borne flavivirus circulating in Asia and Africa. In 2013, a large outbreak was reported on the archipelago of French Polynesia. In this study, we report the detection and molecular characterization of Zika virus for the first time in Chile from an outbreak among the inhabitants of Easter Island. A total of 89 samples from patients suspected of having ZIKV infection were collected between the period from January to May, 2014. Molecular diagnosis of the virus was performed by RT-PCR followed by the sequencing of the region containing the NS5 gene. A comparison of the viral nucleic acid sequence with those of other strains of ZIKA virus was performed using the MEGA software. Fifty-one samples were found positive for ZIKV by RT-PCR analysis. Further analysis of the NS5 gene revealed that the ZIKV strains identified in Easter Island were most closely related to those found in French Polynesia (99.8 to 99.9% nt and 100% aa sequence identity). These results strongly suggest that the transmission pathway leading to the introduction of Zika virus on Easter Island has its origin in French Polynesia.


Assuntos
Surtos de Doenças , Infecção por Zika virus/epidemiologia , Zika virus/isolamento & purificação , Análise por Conglomerados , Humanos , Epidemiologia Molecular , Filogenia , Polinésia/epidemiologia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência , Zika virus/classificação , Zika virus/genética
8.
Epidemiol Infect ; 143(14): 3069-73, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25687254

RESUMO

Clostridium difficile infection has gained importance in recent years as a result of the rapid spread of epidemic strains, including hypervirulent strains. This study reports the molecular epidemiology of C. difficile obtained from hospitalized patients in Chile. Seven hundred and nineteen isolates of toxigenic C. difficile from 45 hospitals across the country were characterized through toxin profile, pulsed-field gel electrophoresis (PFGE), and sequencing of the tcdC gene. In addition, polymerase chain reaction (PCR) ribotyping and multilocus sequence typing (MLST) were performed on a subset of selected strains. PFGE typing of 719 isolates of C. difficile produced 60 PFGE patterns (subtypes). Subtype 1 was predominant (79% of isolates) and related to the hypervirulent strain (NAP1). Subtype 1 showed 73% relatedness with nine other subtypes, which had a similar tcdC deletion. Subtype 1 corresponded to ribotype 027 and ST1. This report shows the wide dissemination of the hypervirulent strain NAP1/027/ST1 in Chile.


Assuntos
Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Epidemias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Toxinas Bacterianas/genética , Criança , Pré-Escolar , Chile/epidemiologia , Clostridioides difficile/classificação , Clostridioides difficile/genética , Análise por Conglomerados , Eletroforese em Gel de Campo Pulsado , Feminino , Genótipo , Hospitais , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Ribotipagem , Adulto Jovem
9.
Acta pediatr. esp ; 71(9): e287-e292, oct. 2013. ilus
Artigo em Espanhol | IBECS | ID: ibc-129425

RESUMO

La obstrucción nasal es un síntoma frecuente de consulta en otorrinolaringología pediátrica, y su etiología más frecuente es la hipertrofia adenoidea. Los pólipos antrocoanales son una entidad clínica infrecuente que representa el 28-33% de las poliposis nasosinusales en la población infantil. Presentamos el caso clínico de una niña de 8 años de edad, adenoidectomizada, con síntomas de insuficiencia respiratoria nasal, rinorrea en ocasiones purulenta y cefaleas frontoorbitarias sin epistaxis. El estudio endoscópico nasal y las pruebas de imagen diagnosticaron la presencia de una lesión polipoidea que ocupaba ambas fosas nasales y coanas, siendo tratada mediante cirugía endoscópica nasosinusal. El estudio histológico informó de la presencia de un pólipo antrocoanal y el estudio alérgico mediante prick-test descartó la existencia de alergias. Hoy en día aún no disponemos de la suficiente evidencia histológica y/o alergológica que determine la etiología de los pólipos antrocoanales (AU)


Nasal obstruction is a frequent symptom of consultation in pediatric otolaryngology, and its most common etiology is adenoidal hypertrophy. Antrochoanal polyps are an uncommon clinical entity that represents 28-33% of the sinonasal polyposis in children. We report the case of an 8-year-old child, with previous adenoidectomy, with symptoms of nasal obstruction, purulent rhinorrhea, headache frontoorbitarias without epistaxis. The nasal endoscopy and imaging tests diagnosed the presence of a polypoid lesion occupying both nostrils and choanae, being treated by endoscopic sinus surgery. Histology disclosed an antrochoanal polyp and allergy study by prick-test ruled out the existence of allergies. Today, we have not yet sufficient histological and/or allergological evidence to determine the etiology of polyps antrochoanal (AU)


Assuntos
Humanos , Feminino , Criança , Pólipos Nasais/complicações , Pólipos Nasais/diagnóstico , Pólipos Nasais/cirurgia , Obstrução Nasal/complicações , Obstrução Nasal/cirurgia , Obstrução Nasal , Pólipos Nasais/fisiopatologia , Pólipos Nasais , Hipertrofia/complicações , Hipertrofia
10.
Br J Nutr ; 104(1): 83-92, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20205964

RESUMO

Obesity is associated with complications during pregnancy and increased health risks in the newborn. The objective of the present study was to establish possible relationships between gut microbiota, body weight, weight gain and biochemical parameters in pregnant women. Fifty pregnant women were classified according to their BMI in normal-weight (n 34) and overweight (n 16) groups. Gut microbiota composition was analysed by quantitative real-time PCR in faeces and biochemical parameters in plasma at 24 weeks of pregnancy. Reduced numbers of Bifidobacterium and Bacteroides and increased numbers of Staphylococcus, Enterobacteriaceae and Escherichia coli were detected in overweight compared with normal-weight pregnant women. E. coli numbers were higher in women with excessive weight gain than in women with normal weight gain during pregnancy, while Bifidobacterium and Akkermansia muciniphila showed an opposite trend. In the whole population, increased total bacteria and Staphylococcus numbers were related to increased plasma cholesterol levels. Increased Bacteroides numbers were related to increased HDL-cholesterol and folic acid levels, and reduced TAG levels. Increased Bifidobacterium numbers were related to increased folic acid levels. Increased Enterobacteriaceae and E. coli numbers were related to increased ferritin and reduced transferrin, while Bifidobacterium levels showed the opposite trend. Therefore, gut microbiota composition is related to body weight, weight gain and metabolic biomarkers during pregnancy, which might be of relevance to the management of the health of women and infants.


Assuntos
Bactérias/isolamento & purificação , Biomarcadores/sangue , Peso Corporal , Colo/microbiologia , Sobrepeso/etiologia , Complicações na Gravidez/etiologia , Aumento de Peso , Adulto , Índice de Massa Corporal , Colesterol/sangue , HDL-Colesterol/sangue , Fezes/microbiologia , Feminino , Ferritinas/sangue , Ácido Fólico/sangue , Humanos , Lipídeos/sangue , Sobrepeso/sangue , Gravidez , Complicações na Gravidez/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transferrina/metabolismo , Triglicerídeos/sangue
12.
Anal Bioanal Chem ; 389(6): 1901-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17899033

RESUMO

A liquid chromatography-electrospray-tandem mass spectrometry (LC-ESI-MS-MS) method based on the detection of biomarker peptides from allergenic proteins was devised for confirming and quantifying peanut allergens in foods. Peptides obtained from tryptic digestion of Ara h 2 and Ara h 3/4 proteins were identified and characterized by LC-MS and LC-MS-MS with a quadrupole-time of flight mass analyzer. Four peptides were chosen and investigated as biomarkers taking into account their selectivity, the absence of missed cleavages, the uniform distribution in the Ara h 2 and Ara h 3/4 protein isoforms together with their spectral features under ESI-MS-MS conditions, and good repeatability of LC retention time. Because of the different expression levels, the selection of two different allergenic proteins was proved to be useful in the identification and univocal confirmation of the presence of peanuts in foodstuffs. Using rice crisp and chocolate-based snacks as model food matrix, an LC-MS-MS method with triple quadrupole mass analyzer allowed good detection limits to be obtained for Ara h 2 (5 microg protein g(-1) matrix) and Ara h 3/4 (1 microg protein g(-1) matrix). Linearity of the method was established in the 10-200 microg g(-1) range of peanut proteins in the food matrix investigated. Method selectivity was demonstrated by analyzing tree nuts (almonds, pecan nuts, hazelnuts, walnuts) and food ingredients such as milk, soy beans, chocolate, cornflakes, and rice crisp.


Assuntos
Alérgenos/análise , Biomarcadores/análise , Análise de Alimentos/métodos , Fragmentos de Peptídeos/análise , Proteínas de Plantas/análise , Albuminas 2S de Plantas , Alérgenos/química , Antígenos de Plantas , Cromatografia Líquida/métodos , Glicoproteínas/análise , Glicoproteínas/química , Fragmentos de Peptídeos/química , Proteínas de Plantas/química , Isoformas de Proteínas/análise , Isoformas de Proteínas/química , Proteínas de Armazenamento de Sementes , Espectrometria de Massas em Tandem/métodos , Fatores de Tempo
14.
J Biotechnol ; 118(3): 316-27, 2005 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-16019100

RESUMO

Monitoring cell growth is crucial to the success of an animal cell culture process that can be accomplished by a variety of direct or indirect methodologies. Glucose is a major carbon and energy source for cultured mammalian cells in most cases, but glycolytic metabolism often results in the accumulation of lactate. Glucose and lactate levels are therefore routinely measured to determine metabolic activities of a culture. Typically, neither glucose consumption rate nor lactate accumulation rate has a direct correlation with cell density due to the changes in culture environment and cell physiology. We discovered that although the metabolic rate of glucose or lactate varies depending on the stages of a culture, the cumulative consumption of glucose and lactate combined (Q(GL)) exhibits a linear relationship relative to the integral of viable cells (IVC), with the slope indicating the specific consumption rate of glucose and lactate combined (q(GL)). Additional studies also showed that the q(GL) remains relatively constant under different culture conditions. The insensitivity of the q(GL) to process variations allows a potentially easy and accurate determination of viable cell density by the measurement of glucose and lactate. In addition, the more predictable nature of a linear relationship will aid the design of better forward control strategies to improve cell culture processes.


Assuntos
Reatores Biológicos , Células CHO/fisiologia , Técnicas de Cultura de Células/métodos , Glucose/metabolismo , Ácido Láctico/metabolismo , Monitorização Fisiológica/métodos , Animais , Proliferação de Células , Cricetinae , Cricetulus , Concentração de Íons de Hidrogênio , Taxa de Depuração Metabólica , Temperatura
15.
Prog. obstet. ginecol. (Ed. impr.) ; 46(10): 467-469, oct. 2003. ilus
Artigo em Es | IBECS | ID: ibc-26072

RESUMO

Presentamos un caso de evisceración vaginal en una mujer posmenopáusica sometida, 6 meses antes, a histerectomía vaginal, cuya reparación se realizó por vía abdominal mediante cierre de la cúpula vaginal y colocación de malla de Gore-Tex® para refuerzo del suelo pelviano. El diagnóstico y la reparación tempranos de este raro problema urgente llevan a evitar la resección intestinal y a una buena recuperación de las pacientes. En la intervención debe valorarse la presencia de defectos del suelo pelviano que contribuyan a la evisceración. (AU)


Assuntos
Idoso , Feminino , Humanos , Histerectomia/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Prolapso Uterino , Doenças Vaginais/cirurgia , Intussuscepção/cirurgia , Doenças Vaginais/etiologia , Pós-Menopausa , Diafragma da Pelve/lesões
16.
Artigo em Inglês | MEDLINE | ID: mdl-10425731

RESUMO

The phenotypic response of digestive enzymes was assessed in two species of rodents with different foods habits. Species were Phyllotis darwini (omnivorous) and Octodon degus (herbivorous). The activity of sucrase, maltase and aminopeptidase-N were determined in vitro in animals feeding two contrasting diets. No effect of dietary chemistry on sucrase and maltase activities was observed. Nevertheless, aminopeptidase-N showed a reversible response to diet in P. darwini but not in O. degus. Through Principal Component Analysis we separated the specific and non-specific modulation of the enzymes. The analysis showed that aminopeptidase-N activity is up-regulated by dietary protein in P. darwini. Differences in the phenotypic response of this species apparently reflect the historic levels of specific substrates of the natural diets for this enzyme, linking dietary flexibility and digestive plasticity in an evolutionary context.


Assuntos
Adaptação Fisiológica/fisiologia , Dieta , Enzimas/metabolismo , Modelos Biológicos , Roedores/fisiologia , Análise de Variância , Animais , Antígenos CD13/metabolismo , Sistema Digestório/enzimologia , Muridae , Roedores/metabolismo , Sacarase/metabolismo , alfa-Glucosidases/metabolismo
17.
Angiology ; 45(11): 931-6, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7978506

RESUMO

Cardiac rupture complicating acute myocardial infarction (AMI) remains a serious diagnostic and therapeutic challenge. The authors present 27 consecutive patients who died from cardiac rupture following AMI. These included 22 patients from 1975 through 1983 (prethrombolytic era) and 5 patients from 1984 through 1992 (postthrombolytic era) and all had postmortem examination. There were 16 men and 11 women with a mean age of seventy-two years. Myocardial infarction was anterior/anterolateral in 10 and inferior/inferoposterior in 17. Cardiac rupture followed AMI within one day in 14 (52%), two to five days in 8 (30%), and six to fourteen days in 5 (18%). Chest pain followed by sudden hypotension leading to electromechanical dissociation was the common terminal event. Cardiopulmonary resuscitation was unsuccessful in all patients. Postmortem findings showed three-vessel coronary disease in 21 (78%) and two-vessel disease in 6 (22%). Isolated free left ventricular wall rupture was found in 22 (81%), was anterior/anterolateral in 13 (48%), posterior in 9 (33%), and in conjunction with interventricular septum or papillary muscle in 5 (18%). Patients encountered in this series were mostly elderly hypertensives with multivessel coronary disease and postinfarction angina. Furthermore, cardiac rupture commonly occurred within the first five days of AMI and cardiopulmonary resuscitation was uniformly unsuccessful. During the thrombolytic era at their institution, this complication is now being seen much less often. These observations suggest that such interventions are expected to have a favorable impact on reducing the incidence of this catastrophic event.


Assuntos
Ruptura Cardíaca Pós-Infarto/mortalidade , Terapia Trombolítica , Idoso , Feminino , Ruptura Cardíaca Pós-Infarto/patologia , Ruptura Cardíaca Pós-Infarto/prevenção & controle , Humanos , Incidência , Masculino
18.
Cancer ; 71(11): 3531-40, 1993 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-8490901

RESUMO

BACKGROUND: The S-phase fraction relates to proliferation, an important determinant of tumor behavior, and has been measured most accurately with the DNA precursor tritiated thymidine (TT). The TT labeling index (LI) is a strong stage-independent prognostic indicator for breast carcinoma. The thymidine analogue 5-bromodeoxyuridine (BrdU) is also incorporated into DNA and has the advantage over TT of immunohistochemical detectability rather than requiring autoradiography, but it is less well studied in breast carcinoma. This report demonstrates the equivalence of TT and BrdU LI and explores the relationships between LI and other biologic measurements. METHODS: The LI of 234 consecutive breast carcinomas were measured with TT as was a subsequent series of 450 cases with BrdU, both by incubation in vitro. RESULTS: The mean BrdU LI was 6.4 +/- 0.3% in comparison with 6.9 +/- 0.4% in the prior TT series. LI was unaffected by storage for 24 hours at 4 degrees C before labeling with BrdU. The BrdU and TT LI both correlated: (1) positively with tumor size, histologic type, nuclear size, the number of axillary metastases, the level of DNA ploidy, and the percent S-phase by flow cytometry and (2) negatively with the age of the patient and the levels of estrogen receptor and progesterone receptor measured either by ligand binding or by immunohistochemistry. CONCLUSIONS: BrdU labeling in vitro was an advantageous method for measuring S-phase fraction in breast carcinoma that produced results comparable to those from TT labeling. It should be equally effective for breast cancer kinetic classification and prognosis and is a suitable standard to evaluate newer methods for measuring cellular proliferation.


Assuntos
Neoplasias da Mama/patologia , Bromodesoxiuridina/metabolismo , Carcinoma/patologia , Fase S , Neoplasias da Mama/metabolismo , Carcinoma/metabolismo , Criopreservação , Feminino , Humanos , Técnicas In Vitro , Timidina/metabolismo
19.
Rev Esp Cardiol ; 45(8): 520-4, 1992 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-1470742

RESUMO

The natural course of post myocardial infarction ventricular septal defect is towards cardiogenic shock and death. 50% in the first week, over 90% a year latter. Between 1973-1989, 28 patients where operated on. Before surgery 14 patients (53%) where in Killip IV, 5 patients (19%) in III, 5 patients (19%) in II and 2 patients in I. The repair was accomplished under hypothermia and cardioplegia, with the insertion of a Teflon patch to close the defect in 20 patients (70%). Complementary procedures (CABG, Pacemaker, repair of dissections) were performed in 12 patients (47%). Three patients (10%) could not be weaned from the pump; another 10 (36%) died before discharge: 2 with multisystem failure and sepsis, the other 8 with cardiogenic shock (4 with residual VSD). The only independent predictor of operative mortality, by univariate analysis, was preoperatory cardiogenic shock. All 15 survivors (100%) where followed between 5 months and 14.5 years (mean 104.5 months). Two patients died at 4 years, one at 10, another at 10.5 years. The actuarial probability of being alive after discharge was 100% at 4 years, 75% at 5, and 50% at 10 years. At last follow up only 2 patients had mild dyspnea, the remaining where asymptomatic. Surgical treatment provides an opportunity to improve this otherwise dismal survival and offers a surprising good long term result. An early diagnosis and efficient repair, before the onset of cardiogenic shock, should provide better results.


Assuntos
Ruptura Cardíaca Pós-Infarto/cirurgia , Análise Atuarial , Adulto , Idoso , Feminino , Seguimentos , Ruptura Cardíaca Pós-Infarto/diagnóstico , Ruptura Cardíaca Pós-Infarto/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo
20.
Artigo em Espanhol | LILACS | ID: lil-116726

RESUMO

Entre 1985 y 1989 tratamos a doce pacientes con traumatismo grave de extremidades por proyectiles de alta velocidad, la mayoría de ellos, producto de entrenamiento militar. Nueve de ellos presentaron compromiso de las extremidades inferiores. La lesión vascular se acompañó de lesión ósea y de partes blandas en todos los casos. La conducta terapéutica fue fijación de la extremidad por medio de tutores externos, la reparación arterial con resección y anastomósis término terminal, o bien injerto de vena safena o PTFE, este último en cinco casos. Venorrafia se efectúa en cinco casos. La cobertura de partes blandas se hizo con rotación de colgajo cutáneo (cuatro casos), injerto de latissimus dorsi utilizando anastomosis vascular con técnica microquirúrgica en una ocasión y en siete con injerto cutáneo fenestrado. Se obtuvo recuperación funcional completa de diez pacientes y en sólo una de la serie se debió recurrir a una amputación mayor por fracaso de la revascularización e infección


Assuntos
Humanos , Masculino , Adulto , Traumatismos do Braço , Ferimentos por Arma de Fogo , Traumatismos da Perna , Procedimentos Cirúrgicos Vasculares
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