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1.
Braz J Biol ; 83: e268859, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37132741

RESUMEN

The use of medicinal plants as raw material for extracts production and pure substances isolation and subsequence development of new drugs represents a constantly growing area. However, some stages are indispensable before pharmacologically evaluating natural products such as medicines. Toxicity tests in mammalian cells are essential to initiate new drugs development or verify the substance's biocompatibility. Thus, we verified the toxicity of crude extracts and fractions with different polarities obtained from the leaves and stems of eight plant species. The toxic effect was evaluated on macrophages obtained from the bone marrow and peritoneal cavity of a Swiss webster mouse and J774 macrophages. G8 cell lineage. These macrophages were cultured in a 96-well plate, and the compounds were added at a concentration of 100 µg/mL for 24 hours. After this time, the supernatant was removed. The toxicity was evaluated for lactate dehydrogenase (LDH) release assay and the resazurin assay, which uses an indicator dye to measure oxidation-reduction reactions. The results showed a difference in the percentage of toxicity when comparing the same extract in different types of macrophages. This outcome indicates that these cells from different origins may exhibit different responses when exposed to the same natural compounds.


Asunto(s)
Extractos Vegetales , Plantas Medicinales , Ratones , Animales , Extractos Vegetales/toxicidad , Macrófagos , Hojas de la Planta , Mamíferos
2.
J Anim Sci ; 94(1): 359-76, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26812341

RESUMEN

The objective of this study was to assess the relationship between the animal welfare conditions evaluated through the supply chain and pork quality variation. A total of 4,680 pigs from 12 farms-5 animal welfare improved raising system (AWIRS) and 7 conventional raising system (CON) farms-were assessed from farm to slaughter through a comprehensive audit protocol merging the European Welfare Quality, the Canadian Animal Care Assessment, and American Meat Institute audit guide criteria. At the abattoir, a subsample of 1,440 pigs (120 pigs/farm) was randomly chosen out of 24 loads (2 farms per wk) transported by 2 drivers (driver A and driver B) for the assessment of stunning effectiveness, carcass bruises, blood lactate levels, and meat quality traits. Meat quality was assessed in the longissimus lumborum (LL) muscle 24 h postmortem by measuring ultimate pH (pHu), color (L*, a*, and b*), and drip loss. Data were analyzed by the MIXED, GLIMMIX, and NAPAR1WAY procedures of SAS. Spearman correlations were calculated to determine the relationship between audit scores and meat quality traits. Better animal welfare conditions, as showed by greater final scores for good housing (GHo; = 0.001) and good health ( = 0.006) principles, were recorded at AWIRS farms. Pigs from AWIRS farms handled by driver B displayed a greater percentage of turning back ( = 0.01) and slips ( < 0.001) during unloading and a greater ( = 0.02) frequency of falls in the stunning chute. A greater ( = 0.02) reluctance to move at loading was found in CON pigs loaded by driver A compared with driver B, whereas a greater ( < 0.001) reluctance to move was found in these pigs at unloading when they were unloaded by driver B. Drip loss was higher ( = 0.003) and pale, soft, and exudative pork percentage was greater ( < 0.001) in the LL muscle of the heavier AWIRS pigs. The GHO principle was best correlated with pHu ( = -0.75, = 0.01) and Minolta L* value ( = 0.87, < 0.001) of the LL muscle. Overall, drip loss variation in the LL muscle was correlated with the frequency of slips at unloading ( = 0.63, = 0.001) and in the restrainer area ( = 0.74, < 0.001). The results of this study showed that the quality of the raising system and truck driver skills as assessed by animal welfare audit protocols are important sources of variation in the behavioral response of pigs to preslaughter handling and may affect pork quality variation. However, the different live weight between CON and AWIRS pigs may have biased the meat quality results in this study.


Asunto(s)
Crianza de Animales Domésticos/ética , Bienestar del Animal/normas , Carne/normas , Mataderos , Crianza de Animales Domésticos/métodos , Animales , Canadá , Porcinos , Transportes
3.
Animal ; 9(4): 707-14, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25399703

RESUMEN

The objectives of this study were to assess the relationship between blood lactate variation measured at the plant, and pork quality variation on a large sample size and under commercial preslaughter handling conditions. A total of 600 pigs were randomly chosen on arrival at a commercial slaughter plant and blood samples taken from the ear vein at unloading (UN), after lairage (LA), in the restrainer (RE; before stunning) and at exsanguination (EX) were analysed for lactate content using a Lactate Scout Analyzer (LSA). In order to have a large range of measures, pigs were distributed into two groups; one kept in lairage overnight (G1) and the other for 2 to 3 h (G2) before slaughter. Meat quality was assessed in the Longissimus thoracis (LT), Semimembranosus (SM) and Adductor (AD) muscles by measuring the pH 30 min postmortem (pH1) and at 24 h postmortem (pHu), the colour and the drip loss. Blood lactate levels did not differ between G1 and G2 (P>0.05). A reduced muscle lactate and glucose contents (P=0.02 and P=0.004, respectively) resulting in a lower (P<0.001) glycolytic potential (GP) was observed in the LT muscle of G1 pigs when compared with G2 loins. In the LT muscle of G1 pigs, the lower GP resulted in an increased pHu (r=-0.67; P<0.001), decreased drip loss (r=0.57; P<0.001) and darker colour (r=0.50; P<0.001) compared with G2. In both G1 and G2 pigs, the lower GP was correlated to higher pHu value in the SM and AD muscles (r=-0.73; P<0.001). The greatest correlation was observed in G2 between blood lactate levels at LA and pHu value of the SM and AD muscles (r=0.46 and r=0.44, respectively; P<0.001 for both muscles). The second greatest correlation was found between blood lactate levels at EX and pH1 value in the SM muscle in both groups (r=-0.37 and r=-0.41, respectively; P<0.001 for both groups). Based on the results of this study, it appears that blood lactate levels, as measured by the LSA, reliably reflect the physiological response of pigs to perimortem stress and may help explain the variation in pork quality.


Asunto(s)
Fatiga/sangre , Ácido Láctico/sangre , Carne/normas , Animales , Fatiga/metabolismo , Glucólisis/fisiología , Músculo Esquelético/metabolismo , Porcinos/sangre , Porcinos/fisiología
4.
J Anim Sci ; 91(8): 3965-77, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23658339

RESUMEN

The objective of this study was to evaluate the effects of ractopamine supplementation, castration method, and their interaction on the behavioral and physiological response to preslaughter stress and carcass and meat quality of 2 Piétrain genotypes. A total of 1,488 male pigs (115 ± 5 kg BW) were distributed according to a 2 × 2 × 2 factorial arrangement of treatments. The first factor was ractopamine supplementation with 2 groups of pigs (376 and 380 pigs each) receiving 7.5 mg/kg of ractopamine (RAC) or not (NRAC) in their diet during the last 28 d of the finishing period. The second factor was castration method, with 744 surgical castrates (SC) and 744 immunized males (IM), and the third factor was the genotype with 2 crossbreeds containing 50% (genotype A, GA; n = 744) or 25% (genotype B, GB; n = 744) Piétrain genetics. Surgical castration took place at 2 d of age, whereas immunization against gonadotropin-releasing factor (GnRF) was performed through 2 subcutaneous injections of GnRF analog (Improvest, 2 mL) at 10 and 4 wk before slaughter. At loading more vocal stimulation was needed by the handler to drive GB pigs forward through the farm alley (P = 0.01) and RAC-fed GB pigs through the ramp (P = 0.02). Feeding RAC to IM increased the number of fights in lairage compared with SC (P = 0.03). Feeding RAC shortened fighting bouts compared with NRAC pigs (P = 0.05). The SC-GA pigs showed a greater gastrointestinal tract temperature during unloading (P = 0.05) and lairage time (P = 0.03). Blood creatine kinase (CK) concentrations were greater (P = 0.04) in SC compared with IM, and no difference was found in the concentrations of stress hormones in urine collected postmortem. Dressing yield was greater (P = 0.01) in RAC and SC-GB pigs. Carcasses from RAC pigs and IM were leaner than those from NRAC and SC pigs (P < 0.001 and P = 0.002, respectively). Feeding RAC to IM increased drip loss in the LM (P = 0.05). Warner-Bratzler shear force values were slightly greater in the LM from RAC-GB pigs and from IM compared with SC (P = 0.01 and P < 0.001, respectively) and in the semimembranosus muscle of RAC pigs (P = 0.006). In conclusion, immunization against GnRF more than the use of Piétrain genotypes appears to be a viable alternative to the use of ractopamine, as it seems to promote production of lean carcasses without compromising animal welfare and pork quality.


Asunto(s)
Composición Corporal/efectos de los fármacos , Genotipo , Carne/normas , Orquiectomía/veterinaria , Fenetilaminas/farmacología , Estrés Fisiológico/efectos de los fármacos , Animales , Conducta Animal , Temperatura Corporal , Masculino , Orquiectomía/métodos , Porcinos/genética , Porcinos/fisiología
5.
Pac Symp Biocomput ; : 409-20, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23424145

RESUMEN

BACKGROUND: Drug-drug interaction (DDI) is a major cause of morbidity and mortality. DDI research includes the study of different aspects of drug interactions, from in vitro pharmacology, which deals with drug interaction mechanisms, to pharmaco-epidemiology, which investigates the effects of DDI on drug efficacy and adverse drug reactions. Biomedical literature mining can aid both kinds of approaches by extracting relevant DDI signals from either the published literature or large clinical databases. However, though drug interaction is an ideal area for translational research, the inclusion of literature mining methodologies in DDI workflows is still very preliminary. One area that can benefit from literature mining is the automatic identification of a large number of potential DDIs, whose pharmacological mechanisms and clinical significance can then be studied via in vitro pharmacology and in populo pharmaco-epidemiology. EXPERIMENTS: We implemented a set of classifiers for identifying published articles relevant to experimental pharmacokinetic DDI evidence. These documents are important for identifying causal mechanisms behind putative drug-drug interactions, an important step in the extraction of large numbers of potential DDIs. We evaluate performance of several linear classifiers on PubMed abstracts, under different feature transformation and dimensionality reduction methods. In addition, we investigate the performance benefits of including various publicly-available named entity recognition features, as well as a set of internally-developed pharmacokinetic dictionaries. RESULTS: We found that several classifiers performed well in distinguishing relevant and irrelevant abstracts. We found that the combination of unigram and bigram textual features gave better performance than unigram features alone, and also that normalization transforms that adjusted for feature frequency and document length improved classification. For some classifiers, such as linear discriminant analysis (LDA), proper dimensionality reduction had a large impact on performance. Finally, the inclusion of NER features and dictionaries was found not to help classification.


Asunto(s)
Interacciones Farmacológicas , Inteligencia Artificial , Biología Computacional , Minería de Datos/estadística & datos numéricos , Bases de Datos Factuales/estadística & datos numéricos , Análisis Discriminante , Humanos , Farmacocinética , Fenómenos Farmacológicos , PubMed/estadística & datos numéricos
6.
Genet Mol Res ; 12(4): 6838-49, 2013 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-24391031

RESUMEN

Differences in cellular and humoral immunity in Zebu (Bos taurus indicus) and European (B. taurus taurus) cattle breeds, which may be related to differences in resistance or susceptibility to infectious or parasitic diseases, are largely unknown. This study aimed to perform a comparative analysis of innate and adaptive immunity of European (including Holstein, Brown Swiss, and Hereford) and Zebu (including Gir, Nelore, and Guzera) breeds, by assessing their peripheral blood leukocyte profiles (i.e., monocytes, eosinophils, and lymphocytes, including CD4(+) and CD8(+) T cells, and CD21(+) B cells). Higher frequencies of cells involved in innate immunity were observed in Zebu breeds, particularly monocytes and non-T and non-B cells (13.37 ± 0.9058 and 37.67 ± 1.55, respectively). This finding may contribute to the increased resistance of B. taurus indicus to certain infectious and parasitic diseases. Considering other leukocyte populations in the peripheral blood, among-breed variation was greater than differences between the two subspecies. This study will serve as a basis for further investigations regarding comparative immunology and resistance to infectious and parasitic diseases of cattle.


Asunto(s)
Inmunidad Adaptativa , Bovinos/inmunología , Inmunidad Innata , Inmunofenotipificación/veterinaria , Animales , Linfocitos B/inmunología , Eosinófilos/inmunología , Femenino , Leucocitos/inmunología , Masculino , Monocitos/inmunología , Fenotipo , Linfocitos T/inmunología
7.
J. venom. anim. toxins incl. trop. dis ; 16(1): 121-130, 2010. tab
Artículo en Inglés | LILACS | ID: lil-542434

RESUMEN

The present study aimed at investigating the chemical composition of essential oil extracted from Brazilian propolis and the susceptibility of Staphylococcus aureus, Staphylococcus epidermides, Streptococcus pyogenes and Escherichia coli to this substance. The essential oil was obtained by steam distillation of propolis and examined by gas chromatography/mass spectrometry (GC/MS). In addition, the agar diffusion method using filter paper disks was employed. Antibacterial activity was measured as equivalent diameters of inhibition zones (in millimeters) after incubation at 37ºC for 24 hours. From the 26 identified constituents, Beta-caryophyllene (12.7 percent), acetophenone (12.3 percent) and Beta-farnesene (9.2 percent) were found to be major components. New components, namely linalool, methyl hydrocinnamate, ethyl hydrocinnamate, alfa-ylangene, gama-elemene and valencene, are reported for the first time to be present in propolis essential oil. This oil also exhibited antibacterial activity.


Asunto(s)
Abejas , Aceites Volátiles , Própolis/farmacología , Própolis/química , Escherichia coli , Staphylococcus aureus , Staphylococcus epidermidis , Streptococcus pyogenes
8.
Transplant Proc ; 39(2): 441-2, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17362753

RESUMEN

UNLABELLED: Various strategies have evolved to expand the donor pool due to the extreme shortage of organs. Herein we reviewed our experience with en bloc pediatric kidney transplantation since 1998. METHODS: From January 1998 to December 2004, nine adult patients underwent kidney transplantation using en bloc kidneys from donors <5 years old (range, 1 to 4). The mean age of the recipients was 45.1 years (range, 34 to 57). RESULTS: In recipients of en bloc pediatric transplantation, cold ischemia time ranged from 14 to 26.2 hours (mean, 21.3 hours). Mean serum creatinine at 3, 6, and 12 months after transplantation was 1.53 +/- 0.57, 1.27 +/- 0.27, and 1.15 +/- 0.26 mg/dL compared with 1.93 +/- 1.35, 1.81 +/- 1.17, and 1.73 +/- 0.85 (P = .08) in recipients of single kidneys from ideal cadaveric donors (UNOS criteria, n = 368). Patient and graft survival at 1 year were 88.8% compared with 91.2% and 85% with ideal donors (P = NS), respectively. Three cases required additional surgery. There was one death due to a cerebral vascular accident. CONCLUSION: The present study confirmed the excellent results achieved with transplantation using en bloc kidneys from young donors.


Asunto(s)
Trasplante de Riñón/fisiología , Donantes de Tejidos/estadística & datos numéricos , Adulto , Cadáver , Niño , Preescolar , Creatinina/sangre , Humanos , Lactante , Persona de Mediana Edad , Estudios Retrospectivos , Donantes de Tejidos/provisión & distribución
10.
Parasite Immunol ; 27(4): 127-37, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15910421

RESUMEN

Entamoeba histolytica is a human pathogen that may invade the intestinal mucosa, causing amoebic colitis or hepatic abscesses when the trophozoites travel through the portal circulation to the liver. Lipopeptidophosphoglycan (LPPG) is a molecular pattern of E. histolytica recognized by the human immune system. Here we report that LPPG is exposed on the cell surface of E. histolytica trophozoites, and is recognized by the host through toll-like receptor (TLR) 2 and TLR4. Correspondingly, human embryonic kidney (HEK)-293 cells were rendered LPPG responsive through overexpression of TLR2 or TLR4/MD2. Moreover, co-expression of CD14 enhanced LPPG signal transmission through TLR2 and TLR4. The interaction of LPPG with TLR2 and TLR4 resulted in activation of NF-kappaB and release of interleukin (IL)-10, IL-12p40, tumour necrosis factor (TNF)-alpha, and IL-8 from human monocytes. Consistent with these findings, responsiveness of mouse macrophages lacking TLR2 expression (TLR2-/-) or functional TLR4 (TLR4d/d) to E. histolytica LPPG challenge was impaired while double deficient macrophages were unresponsive. In contrast to wild-type control and TLR2-/- animals succumbing to lethal shock syndrome, TLR4d/d mice were resistant to systemic LPPG challenge-induced pathology.


Asunto(s)
Antígenos de Protozoos/inmunología , Entamoeba histolytica/inmunología , Inmunidad Innata , Glicoproteínas de Membrana/inmunología , Peptidoglicano/inmunología , Fosfolípidos/inmunología , Receptores de Superficie Celular/inmunología , Receptores Inmunológicos/inmunología , Animales , Línea Celular , Femenino , Humanos , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Subunidad p40 de la Interleucina-12 , Interleucina-8/metabolismo , Macrófagos/inmunología , Ratones , Ratones Endogámicos C3H , Monocitos/inmunología , FN-kappa B/metabolismo , Subunidades de Proteína/metabolismo , Receptor Toll-Like 2 , Receptor Toll-Like 4 , Receptores Toll-Like , Factor de Necrosis Tumoral alfa/metabolismo
11.
Homeopathy ; 92(4): 177-81, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14587682

RESUMEN

Pruritus is a frequent and difficult to treat problem in haemodialysis. This double-blind placebo-controlled randomised clinical trial assessed the role of homeopathic treatment in this situation. The code was held by the pharmacist who dispensed the medications. Pruritus was evaluated using a previously published scale. Only patients with initial values above 25% of maximum pruritus score were entered. Data were analysed after partial code break, separating the two groups of patients, but with no awareness of which one received verum or placebo. Patients were classified as responders if they had >50% reduction of pruritus score. Twenty-eight patients (16M/12F, 51 +/- 11 years of age) were entered and 20 (12M/8F, 52 +/- 8 years of age) remained for final analysis: 11 in the verum group, 9 in placebo. At entry, the mean pruritus score was 65 +/- 25% for the treated patients and 70 +/- 27% for placebo. After 15, 30, 45, and 60 days of follow-up, pruritus score were respectively: 46 +/- 29, 41 +/- 30, 42 +/- 29, and 38 +/- 33 for the treated patients and 61 +/- 29, 67 +/- 31, 64 +/- 35, and 57 +/- 39 for placebo. Reduction was statistically significant (P<0.05) at every point of observation. According to the patients' own assessment, at the end of the study period, the homeopathic treatment reduced the pruritus score by approximately 49%. Responders were more frequent in the treated group with statistical significance at 30 days (0% vs 45%, P=0.038). Homeopathic treatment may represent a worthwhile alternative to relieve pruritus in patients undergoing haemodialysis.


Asunto(s)
Homeopatía/métodos , Fitoterapia/métodos , Extractos Vegetales/uso terapéutico , Prurito/terapia , Diálisis Renal/efectos adversos , Adulto , Brasil , Método Doble Ciego , Femenino , Humanos , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Prurito/etiología , Factores de Tiempo , Resultado del Tratamiento
12.
Antimicrob Agents Chemother ; 45(7): 1972-6, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11408210

RESUMEN

Rifalazil, also known as KRM-1648 or benzoxazinorifamycin, is a new semisynthetic rifamycin with a long half-life of approximately 60 h. Rifalazil has potent bactericidal activity against Mycobacterium tuberculosis in vitro and in animal models of tuberculosis (TB). Prior studies in healthy volunteers showed that once-weekly doses of 25 to 50 mg of rifalazil were well tolerated. In this randomized, open-label, active-controlled phase II clinical trial, 65 subjects with sputum smear-positive pulmonary TB received one of the following regimens for the first 2 weeks of therapy: 16 subjects received isoniazid (INH) (5 mg/kg of body weight) daily; 16 received INH (5 mg/kg) and rifampin (10 mg/kg) daily; 17 received INH (5 mg/kg) daily plus 10 mg of rifalazil once weekly; and 16 received INH (5 mg/kg) daily and 25 mg of rifalazil once weekly. All subjects were then put on 6 months of standard TB therapy. Pretreatment and day 15 sputum CFU of M. tuberculosis were measured to assess the bactericidal activity of each regimen. The number of drug-related adverse experiences was low and not significantly different among treatment arms. A transient decrease in absolute neutrophil count to less than 2,000 cells/mm(3) was detected in 10 to 20% of patients in the rifalazil- and rifampin-containing treatment arms without clinical consequences. Decreases in CFU counts were comparable among the four treatment arms; however, the CFU results were statistically inconclusive due to the variability in the control arms. Acquired drug resistance did not occur in any patient. Studies focused on determining a maximum tolerated dose will help elucidate the full anti-TB effect of rifalazil.


Asunto(s)
Antibióticos Antituberculosos/uso terapéutico , Rifamicinas/uso terapéutico , Tuberculosis Pulmonar/tratamiento farmacológico , Adolescente , Adulto , Antibióticos Antituberculosos/efectos adversos , Antibióticos Antituberculosos/farmacocinética , Antituberculosos/uso terapéutico , Recuento de Colonia Microbiana , Femenino , Pruebas Hematológicas , Humanos , Isoniazida/uso terapéutico , Pruebas de Función Renal , Pruebas de Función Hepática , Masculino , Rifamicinas/efectos adversos , Rifamicinas/farmacocinética , Tuberculosis Pulmonar/metabolismo , Tuberculosis Pulmonar/microbiología
13.
Int J Tuberc Lung Dis ; 5(4): 321-8, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11334250

RESUMEN

SETTING: Urban public teaching and referral hospital in Espirito Santo, Brazil. OBJECTIVE: To assess whether rates of infection and progression to active tuberculosis (TB) differed between household contacts of patients with multidrug-resistant (MDR) and drug susceptible (DS) pulmonary tuberculosis. DESIGN: Household contacts were assessed for evidence of TB infection and disease by purified protein derivative (PPD) skin testing, physical examination, chest X-ray, and sputum smear and culture. RESULTS: Among 133 close contacts of patients with MDR-TB, 44% were PPD-positive (> or =10 mm) compared to 37% of 231 contacts of the DS-TB cases (P = 0.18, chi2 test, OR 1.2, 95%CI 0.8-2). In a multivariate logistic regression analysis, after allowance for between-household variation in PPD responses, PPD positivity among household contacts of patients with MDR-TB remained comparable to PPD positivity in contacts of patients with DS-TB (OR 2.1, 95%CI 0.7-6.5). Respectively six (4%) and 11 (4%) contacts of the MDR- and DS-TB cases were found to have active TB at the time of initial evaluation or during follow-up (P = 0.78, chi2 test). Five of six contacts of MDR-TB cases and nine of nine contacts of DS-TB cases who developed TB, and for whom drug susceptibility test results were available, had the same bacterial susceptibility profiles as their index cases. DNA fingerprinting analysis of Mycobacterium tuberculosis isolates was identical between household contacts with active TB and the index MDR or DS-TB case for all 14 pairs compared. CONCLUSION: Our data suggest that the prevalence of tuberculous infection and progression to active TB among household contacts exposed to DS and MDR-TB cases is comparable, despite a longer duration of exposure of contacts to the index case in patients with MDR-TB.


Asunto(s)
Transmisión de Enfermedad Infecciosa/estadística & datos numéricos , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Resistente a Múltiples Medicamentos/transmisión , Adolescente , Adulto , Distribución por Edad , Brasil/epidemiología , Estudios de Cohortes , Intervalos de Confianza , Progresión de la Enfermedad , Composición Familiar , Femenino , Hospitales de Enseñanza , Humanos , Control de Infecciones , Masculino , Radiografías Pulmonares Masivas , Persona de Mediana Edad , Oportunidad Relativa , Examen Físico , Prevalencia , Factores de Riesgo , Distribución por Sexo , Esputo/microbiología , Prueba de Tuberculina , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/transmisión , Población Urbana
15.
Biosystems ; 60(1-3): 95-121, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11325506

RESUMEN

Pattee's semantic closure principle is used to study the characteristics and requirements of evolving material symbols systems. By contrasting agents that reproduce via genetic variation with agents that reproduce via self-inspection, we reach the conclusion that symbols are necessary to attain open-ended evolution, but only if the phenotypes of agents are the result of a material, self-organization process. This way, a study of the inter-dependencies of symbol and matter is presented. This study is based first on a theoretical treatment of symbolic representations, and secondly on simulations of simple agents with matter-symbol inter-dependencies. The agent-based simulations use evolutionary algorithms with indirectly encoded phenotypes. The indirect encoding is based on Fuzzy Development programs, which are procedures for combining fuzzy sets in such a way as to model self-organizing development processes.


Asunto(s)
Evolución Biológica , Algoritmos , Biofisica/historia , Lógica Difusa , Variación Genética , Genotipo , Historia del Siglo XX , Modelos Genéticos , Origen de la Vida , Fenotipo , Reproducción , Selección Genética
16.
Am J Nephrol ; 21(1): 51-4, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11275633

RESUMEN

We describe a patient with membranoproliferative glomerulopathy associated with a mixed-cell germinal ovary tumor (embryonal and dysgerminoma components). Advanced renal failure ensued without remission of nephrotic syndrome after surgery. Five other cases of ovary tumor associated with glomerulopathy and reported in the literature are reviewed. The association between membranoproliferative glomerulonephritis and mixed-cell germinal ovary tumor has not been previously reported.


Asunto(s)
Germinoma/complicaciones , Glomerulonefritis Membranoproliferativa/complicaciones , Neoplasias Ováricas/complicaciones , Adolescente , Femenino , Humanos
17.
Antimicrob Agents Chemother ; 45(4): 1302-4, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11257053

RESUMEN

Mycobacterium tuberculosis antigen 85 is induced in vitro by isoniazid (INH); its sustained induction in sputum during tuberculosis (TB) therapy predicts relapse. In this trial, rifampin or rifalazil inhibited the induction of sputum antigen 85 by INH in a dose-dependent fashion. This approach may facilitate the evaluation of new TB drugs.


Asunto(s)
Aciltransferasas , Antígenos Bacterianos/biosíntesis , Antituberculosos/farmacología , Isoniazida/farmacología , Esputo/efectos de los fármacos , Tuberculosis/tratamiento farmacológico , Antibióticos Antituberculosos/uso terapéutico , Biomarcadores/análisis , Recuento de Colonia Microbiana , Humanos , Cinética , Recurrencia , Rifampin/uso terapéutico , Rifamicinas/uso terapéutico , Esputo/metabolismo , Esputo/microbiología , Tuberculosis/metabolismo , Tuberculosis/microbiología
18.
Ann N Y Acad Sci ; 901: 207-23, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10818572

RESUMEN

Two different types of agency are discussed that are based on dynamically coherent and incoherent couplings with an environment, respectively. I propose that until a private syntax (syntactic autonomy) is discovered by dynamically coherent agents, there are no significant or interesting types of closure or autonomy. When syntactic autonomy is established, then, because of a process of description-based selected self-organization, open-ended evolution is enabled. At this stage, in addition to dynamics, agents depend on localized, symbolic memory, thus adding a level of dynamic incoherence to their interaction with the environment. Furthermore, it is the appearance of syntactic autonomy that enables much more interesting types of closures among agents sharing the same syntax. To investigate how we can study the emergence of syntax from dynamic systems, experiments with cellular automata leading to emergent computation that solves nontrivial tasks are discussed. RNA editing is also mentioned as a process that may have been used to obtain a primordial biological code necessary for open-ended evolution.


Asunto(s)
Evolución Biológica , Simbolismo , Código Genético , Edición de ARN
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