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1.
J Environ Manage ; 310: 114722, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35217446

RESUMEN

Rice is a staple food in Senegal, which however imports more than 70% of the rice consumed annually to meet its domestic demand. Despite governmental efforts to increase rice self-sufficiency, both rice supply and yields remain low. Senegalese farmers face challenges related to irrigation infrastructure and fertiliser access, besides those derived from climate change. This study applies Life Cycle Assessment (LCA) combined with financial Life Cycle Costing (LCC) to evaluate alternative scenarios for rice management in the Senegal River Valley and identify sustainability hotspots and potential improvements. Specifically, rice cultivation in Ross Béthio (Saint Louis, Senegal) is assessed based on the observed agricultural practices during the dry seasons of 2016 and 2017. Two scenarios capturing conventional (CONV) and intensive (INT) practices are compared to two reference scenarios (SAED scenarios) according to the recommendations of the official agricultural advisory service. The INT scenario generates the lowest impacts per kg of paddy rice in seven out of thirteen impact categories, including climate change, freshwater and marine eutrophication, ozone depletion and water scarcity. This is due to the higher yields (7.4 t ha-1) relative to CONV (4.8 t ha-1) and the two reference SAED scenarios (6.0 t ha-1). The two latter scenarios show the lowest values in the remaining categories, although they also generate slightly lower profits than INT (138 € t-1 vs. 149 € t-1) due to increased labour costs for additional fertilisation treatments. The results from both LCA and LCC underline the importance of increasing yields to decrease environmental impacts and production costs of rice when estimated per kg of product. Well-designed fertiliser application doses and timing and increased mechanisation can deliver further environmental benefits. Additional improvements (e.g. in irrigation, crop rotations, straw management) could be considered to promote the long-term sustainability and profitability of rice production in Senegal. LCA in combination with financial LCC is identified as a decision-support tool for evaluating the sustainability of alternative crop management practices. Life Cycle Thinking can still benefit from experiential learning based on information exchange between farmers, researchers and extension agents to contribute to a sustainable agriculture and ultimately to food security in Africa.


Asunto(s)
Agricultura , Oryza , Agricultura/métodos , Animales , Ríos , Senegal
2.
J Neurooncol ; 143(1): 107-113, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30830679

RESUMEN

BACKGROUND: Diffuse intrinsic pontine glioma (DIPG) is a devastating cancer of childhood and adolescence. METHODS: The study included patients between 3 and 20 years with clinically and radiologically confirmed DIPG. Primary endpoint was 6-month progression-free survival (PFS) following administration of nimotuzumab in combination with external beam radiotherapy (RT). Nimotuzumab was administered intravenously at 150 mg/m2 weekly for 12 weeks. Radiotherapy at total dose of 54 Gy was delivered between week 3 and week 9. Response was evaluated based on clinical features and MRI findings according to RECIST criteria at week 12. Thereafter, patients continued to receive nimotuzumab every alternate week until disease progression/unmanageable toxicity. Adverse events (AE) were evaluated according to Common Terminology Criteria for Adverse Events (CTC-AE) Version 3.0 (CTC-AE3). RESULTS: All 42 patients received at least one dose of nimotuzumab in outpatient settings. Two patients had partial response (4.8%), 27 had stable disease (64.3%), 10 had progressive disease (23.8%) and 3 patients (7.1%) could not be evaluated. The objective response rate (ORR) was 4.8%. Median PFS was 5.8 months and median overall survival (OS) was 9.4 months. Most common drug-related AEs were alopecia (14.3%), vomiting, headache and radiation skin injury (7.1% each). Therapy-related serious adverse events (SAEs) were intra-tumoral bleeding and acute respiratory failure, which were difficult to distinguish from effects of tumor progression. CONCLUSIONS: Concomitant treatment with RT and nimotuzumab was feasible in an outpatient setting. The PFS and OS were comparable to results achieved with RT and intensive chemotherapy in hospitalized setting.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Neoplasias del Tronco Encefálico/terapia , Quimioradioterapia , Glioma/terapia , Adolescente , Anticuerpos Monoclonales Humanizados/efectos adversos , Antineoplásicos Inmunológicos/efectos adversos , Neoplasias del Tronco Encefálico/diagnóstico por imagen , Quimioradioterapia/efectos adversos , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Glioma/diagnóstico por imagen , Humanos , Masculino , Puente , Análisis de Supervivencia , Resultado del Tratamiento , Adulto Joven
3.
Med Mycol ; 56(2): 253-256, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28525576

RESUMEN

Volatile organic compounds (VOCs) in exhaled breath may identify the presence of invasive pulmonary aspergillosis. We aimed to detect VOC profiles emitted by in vitro cultured, clinical Aspergillus isolates using gas chromatography-mass spectrometry (GC-MS). Three clinical Aspergillus isolates and a reference strain were cultured while conidiation was prevented. Headspace samples were analyzed using a standardized method. Breath samples of patients from which the cultures were obtained were checked for the presence of the VOCs found in vitro. Each Aspergillus isolate produced a distinct VOC profile. These profiles could not be confirmed in exhaled breath in vivo.


Asunto(s)
Aspergillus/metabolismo , Pruebas Respiratorias , Cromatografía de Gases y Espectrometría de Masas , Aspergilosis Pulmonar Invasiva/diagnóstico , Compuestos Orgánicos Volátiles/química , Aspergillus/clasificación , Aspergillus/aislamiento & purificación , Humanos , Aspergilosis Pulmonar Invasiva/fisiopatología
4.
Epidemiol Infect ; 145(5): 981-989, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28065202

RESUMEN

Positive Deviance (PD) is a process to achieve a social and cultural change. This strategy has been used for the control of methicillin-resistant Staphylococcus aureus (MRSA) infection in some health institutions in the United States, but has rarely been adopted in institutions from developing countries where resources are limited. We describe our experience of PD in the control of healthcare-associated infections (HAIs) due to MRSA in a Colombian hospital with the aim of reducing HAI rates through a cultural change in processes. A time-series study was conducted based on the MRSA-HAI rate and the number of months with zero MRSA infections before and after application of PD (2001-2012). On comparing the pre-intervention and intervention periods, the mean overall rates of MRSA-HAI was 0·62 and 0·36, respectively (P = 0·0005); the number of months with zero MRSA-HAIs were 3/70 and 12/74 (odds ratio 0·264, 95% confidence interval 0·078-0·897); the percentage of MRSA-HAIs was 53·2% and 41·0%. These results are consistent with other published data. Implementation of PD was associated with a significant reduction of MRSA-HAIs, it did not involve high costs and the changes have been lasting.


Asunto(s)
Terapia Conductista/métodos , Infección Hospitalaria/prevención & control , Transmisión de Enfermedad Infecciosa/prevención & control , Control de Infecciones/métodos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/prevención & control , Adulto , Colombia/epidemiología , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Adhesión a Directriz , Humanos , Lactante , Recién Nacido , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología
5.
Clin Genet ; 89(4): 461-465, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26346709

RESUMEN

Over 5% of the world's population has varying degrees of hearing loss. Mutations in GJB2 are the most common cause of autosomal recessive non-syndromic hearing loss (ARNHL) in many populations. The frequency and type of mutations are influenced by ethnicity. Guatemala is a multi-ethnic country with four major populations: Maya, Ladino, Xinca, and Garifuna. To determine the mutation profile of GJB2 in a ARNHL population from Guatemala, we sequenced both exons of GJB2 in 133 unrelated families. A total of six pathogenic variants were detected. The most frequent pathogenic variant is c.131G>A (p.Trp44*) detected in 21 of 266 alleles. We show that c.131G>A is associated with a conserved haplotype in Guatemala suggesting a single founder. The majority of Mayan population lives in the west region of the country from where all c.131G>A carriers originated. Further analysis of genome-wide variation of individuals carrying the c.131G>A mutation compared with those of Native American, European, and African populations shows a close match with the Mayan population.

6.
J Clin Densitom ; 19(4): 444-449, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27574779

RESUMEN

The purpose of this study was to evaluate the frequency of osteoporosis (OP) in patients with Gaucher disease (GD) in Argentina. GD patients from 28 centers were consecutively included from April 2012 to 2014. Bone mineral density (BMD) was determined by dual X-ray absorptiometry in the lumbar spine and the femoral neck or the total proximal femur for patients ≥20 yr of age, and by whole-body scan in the lumbar spine in patients <20 yr of age. In children, mineral density was calculated using the chronological age and Z height. OP diagnosis was determined following adult and pediatric official position of the International Society for Clinical Densitometry. A total of 116 patients were included, of which 62 (53.5%) were women. The median age was 25.8 yr. All patients received enzyme replacement therapy, with a median time of 9.4 yr. Normal BMD was found in 89 patients (76.7%), whereas low bone mass (LBM) or osteopenia was found in 15 patients (13%) and OP in 12 patients (10.3%). The analysis of the pediatric population revealed that 4 patients (9.3%) had LBM and 3 (7%) had OP (Z-score ≤ -2 + fractures height-adjusted by Z), whereas in the adult population (n = 73), 11 patients (15%) had LBM or osteopenia and 9 (12.3%) had OP. Bone marrow infiltration and the presence of fractures were significantly correlated with the presence of OP (p = 0.04 and <0.001, respectively). This is the first study in Argentina and in the region describing the frequency of OP or LBM in GD patients treated with imiglucerase using the official position of the International Society for Clinical Densitometry.


Asunto(s)
Absorciometría de Fotón , Enfermedad de Gaucher/complicaciones , Osteoporosis/complicaciones , Osteoporosis/diagnóstico por imagen , Absorciometría de Fotón/métodos , Adolescente , Adulto , Anciano , Argentina/epidemiología , Densidad Ósea , Enfermedades Óseas Metabólicas/complicaciones , Enfermedades Óseas Metabólicas/diagnóstico por imagen , Enfermedades Óseas Metabólicas/epidemiología , Niño , Femenino , Cuello Femoral/diagnóstico por imagen , Enfermedad de Gaucher/epidemiología , Humanos , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Osteoporosis/epidemiología , Adulto Joven
7.
J Fish Biol ; 89(1): 529-36, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27109861

RESUMEN

This study reports for the first time the roles of genetic and body phenotypic variation in two Saccodon dariensis dental morphs. Results showed a lack of ancient mitochondrial differentiation between morphs and body variations concordant with genetic polymorphism or differential plastic responses to diet quality and foraging strategies of S. dariensis.


Asunto(s)
Characiformes/genética , Acrilatos , Animales , Characiformes/anatomía & histología , Characiformes/fisiología , Colombia , Conducta Alimentaria , Femenino , Boca/anatomía & histología , Fenotipo , Éteres Fenílicos , Filogenia , Polimorfismo Genético , Análisis de Secuencia de ADN , Caracteres Sexuales , Diente/anatomía & histología
8.
J Fish Biol ; 89(1): 522-8, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27117920

RESUMEN

Landmark-based geometric morphometrics were used to evaluate the effect of flow and depth in the water column on the body size and shape of Brycon henni from river and stream populations. The dendrogram showed that stream populations clustered apart and showed significantly smaller centroid size and narrower bodies than river populations, indicating a role for flow and depth on whole body morphometric variation. The results are concordant with morphometric variation described in other fish species and provide the first insights into phenotypic variation in natural populations of B. henni.


Asunto(s)
Characiformes/anatomía & histología , Animales , Tamaño Corporal , Characiformes/crecimiento & desarrollo , Femenino , Masculino , Ríos , Caracteres Sexuales , Movimientos del Agua
9.
Stud Hist Philos Biol Biomed Sci ; 84: 101333, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32768176

RESUMEN

In this contribution we seek to enrich the theoretical and methodological approaches of ethnobiology. The essay takes elements of Amerindian anthropology, classical ethnobiological studies and the freedoms provided by feminist philosophers to open up reflection. The central background of the essay is the method of "controlled equivocation" proposed by Viveiros de Castro (2004). We present a series of five ethnobiological equivocations ranging from the categorical equivocal, going through the subtle equivocal to the strictly ontological ones. The cases occurred in different territories of Argentina, including a case in an academic context. Through the fieldwork cases, we give an account of the origin of equivocations, the context for their emergence, which are the disciplinary nuances that cause them and even some academics' preconceptions. To inhabit the equivocation allows opening the possibilities of coexistence among people -and their respective worlds-, especially if these people are in different power positions. We propose the method of controlled equivocation as a theoretical-discursive tool, which permits us to rethink the current concepts of ethnobiology. Thus, we want to broaden the current definition of ethnobiology understood as a dialogue from different scientific points of view.


Asunto(s)
Antropología Cultural , Biología , Conocimiento , Argentina
10.
Parasite Immunol ; 30(4): 195-201, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18324922

RESUMEN

Functional analysis of genes from parasitic helminths requires, at the present time, heterologous expression. We have adapted the well-characterized system of transfection in Leishmania protozoal parasites, as a means of analysing the effect of single filarial genes on the mammalian immune system. For example, testing the function of the Brugia malayi abundant larval transcript (ALT) gene-transfected Leishmania mexicana were found to be significantly more virulent in macrophages in vitro. The course of infection in vivo is also aggravated by expression of the ALT gene. Examples are also given of transgenes which reduced in vitro growth within macrophages, as well as others which exert no effect on the protozoal parasitism. Thus, Leishmania transfection provides a tractable system to analyse helminth gene function within the context of the host immune system.


Asunto(s)
Genes de Helminto , Helmintos/inmunología , Leishmania mexicana/genética , Biología Molecular/métodos , Animales , Helmintos/genética , Transfección
11.
Bol. latinoam. Caribe plantas med. aromát ; 22(4): 508-523, jul. 2023. mapas, tab
Artículo en Español | LILACS | ID: biblio-1556264

RESUMEN

Introduced species generate worldwide concern due to in many cases manifest their potential as invasive as invasives. However, little is known about its sociocultural importance and biocultural interaction. Through open and semi-structured interviews, guided walks and participant observation, the main uses and cultural valuations of biogeographically introduced plants in localities of the Dry Chaco (Catamarca and Córdoba) were investigated. A total of 53 species were documented, 18 with medicinal use and 40 for food. The most recurrent treatments correspond to digestive disorders and respiratory conditions; in food, those for direct consumption stand out. Most taxa with local therapeutic applications coincide with theoretical studies on active principles and their curative effects. Finally, it is concluded that the biogeographic origin of the species is independent of the cultural valuations as long as they are potentially usable, in addition to recognizing that ethnobotanical knowledge based on experience supports the uses found from the academy.


Las especies introducidas generan preocupación mundial debido a que en muchos casos manifiestan su potencialidad como invasoras. Sin embargo, poco se conoce su importancia sociocultural e interacción biocultural. Por medio de entrevistas abiertas y semiestructuradas, caminatas guiadas y observación participante se indagó sobre los principales usos y las valoraciones culturales de las plantas biogeográficamente introducidas en localidades del Chaco Seco (Catamarca y Córdoba). Se documentaron un total de 53 especies, 18 con uso medicinal y 40 alimenticias. Los tratamientos más recurrentes corresponden a trastornos digestivos y afecciones respiratorias; en las alimenticias se destacan aquellas de consumo directo. La mayoría de taxones con aplicaciones terapéuticas locales, coinciden con estudios teóricos sobre principios activos y sus efectos curativos. Finalmente, se concluye que, el origen biogeográfico de las especies es independiente de las valoraciones culturales mientras sean potencialmente aprovechables, además de reconocer que los conocimientos etnobotánicos basados en la experiencia fundamentan los usos encontrados desde la academia.


Asunto(s)
Plantas Medicinales , Especies Introducidas , Medicina Tradicional , Argentina , Encuestas y Cuestionarios , Etnobotánica
12.
J Ethnobiol Ethnomed ; 13(1): 42, 2017 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-28743302

RESUMEN

BACKGROUND: This study was conducted in three rural communities of small farmers of Paraguayan origin living in the province of Misiones, Argentina. These Criollos (Mestizos) hail chiefly from departments located in the east of Paraguay, where the climate and flora have similar characteristics as those in Misiones. These ecological features contribute to the continuation and maintenance of knowledge and practices related to the use of plants. METHODS: Fieldwork was conducted between September 2014 and August 2015. Forty five informants from three rural localities situated along the Parana River participated in an ethno-classification task. For the classification event, photographs of 30 medicinal and edible plants were chosen, specifically those yielding the highest frequency of mention among the members of that community (based on data obtained in the first stage of research in 2014). Variation in local plant classifications was examined and compared using principal component analysis and cluster analysis. RESULTS: We found that people classify plants according to application or use (primarily medicinal, to a lesser extent as edible). Morphology is rarely taken into account, even for very similar and closely-related species such as varieties of palms. In light of our findings, we highlight a dominant functionality model at work in the process of plant cognition and classification among farmers of Paraguayan origin. Salient cultural beliefs and practices associated with rural Paraguayan plant-based medicine are described. Additionally, the manner by which residents' concepts of plants articulate with local folk epistemology is discussed. CONCLUSIONS: Culturally constructed use patterns ultimately override morphological variables in rural Paraguayans' ethnobotanical classification.


Asunto(s)
Emigrantes e Inmigrantes/psicología , Etnobotánica/métodos , Agricultores/psicología , Argentina , Cognición , Cultura , Etnobotánica/clasificación , Humanos , Paraguay/etnología , Plantas Comestibles/clasificación , Plantas Medicinales/clasificación
13.
J Microbiol Methods ; 134: 1-6, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28064034

RESUMEN

Malassezia spp. are part of the normal human and animal mycobiota but are also associated with a variety of dermatological diseases. The absence of a transformation system hampered studies to reveal mechanisms underlying the switch from the non-pathogenic to pathogenic life style. Here we describe, a highly efficient Agrobacterium-mediated genetic transformation system for Malassezia furfur and M. pachydermatis. A binary T-DNA vector with the hygromycin B phosphotransferase (hpt) selection marker and the green fluorescent protein gene (gfp) was introduced in M. furfur and M. pachydermatis by combining the transformation protocols of Agaricus bisporus and Cryptococcus neoformans. Optimal temperature and co-cultivation time for transformation were 5 and 7days at 19°C and 24°C, respectively. Transformation efficiency was 0.75-1.5% for M. furfur and 0.6-7.5% for M. pachydermatis. Integration of the hpt resistance cassette and gfp was verified using PCR and fluorescence microscopy, respectively. The T-DNA was mitotically stable in approximately 80% of the transformants after 10 times sub-culturing in the absence of hygromycin. Improving transformation protocols contribute to study the biology and pathophysiology of Malassezia.


Asunto(s)
Agrobacterium tumefaciens/genética , Malassezia/genética , Transformación Genética , Agaricus/genética , Técnicas de Cocultivo , Cryptococcus neoformans/genética , ADN Bacteriano , Dermatomicosis/microbiología , Vectores Genéticos , Proteínas Fluorescentes Verdes/genética , Humanos , Malassezia/patogenicidad , Microscopía Fluorescente , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Reacción en Cadena de la Polimerasa
14.
J Clin Endocrinol Metab ; 52(6): 1257-9, 1981 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6785300

RESUMEN

Ovulation was induced in a 16-yr-old 46 XX/47 XXY true hermaphrodite with a male phenotype. The presence of testicular tissue was assessed by a normal androgen response to hCG. Administration of FSH and LH for 8 consecutive days, followed by a single dose of hCG, induced a biphasic serum profile of 17 beta-estradiol and progesterone similar to that observed in normal menstrual cycles. In addition, a significant rise in serum testosterone was noticed during the luteal phase. Laparotomy revealed the presence of a uterus, with evidence of endometrial bleeding and absence of a vagina. These results demonstrated that gonadotropins were able to induce follicular maturation, ovulation, and endometrial bleeding in a true hermaphrodite resembling a normal ovulatory cycle. Gonadotropin administration can be used as a diagnostic tool for establishing the presence of ovarian tissue in this gonadal development abnormality.


Asunto(s)
Trastornos del Desarrollo Sexual/fisiopatología , Inducción de la Ovulación , Adolescente , Gonadotropina Coriónica , Dihidrotestosterona/sangre , Trastornos del Desarrollo Sexual/genética , Estradiol/sangre , Hormona Folículo Estimulante , Humanos , Cariotipificación , Hormona Luteinizante , Masculino , Fenotipo , Progesterona/sangre , Testosterona/sangre
15.
Gene ; 199(1-2): 101-9, 1997 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-9358045

RESUMEN

The full length cDNA sequence of a Type I transforming growth factor-beta (TGF-beta) receptor has been isolated from the filarial parasitic nematode Brugia pahangi. This new gene, designated Bp-trk-1, encodes a predicted 645 amino acid sequence with an N-terminal hydrophobic stretch which may act as a signal peptide. The extracellular portion (residues 15-187) is cysteine-rich and has three potential N-glycosylation sites. At positions 250-255 the protein contains the glycine-serine rich motif characteristic of Type I receptors. The closest homologue is a Caenorhabditis elegans gene (Q09488) in cosmid C32D5.2 which shares 67% amino acid identity with Bp-trk-1 in the most conserved kinase domain (aa 259-482). Other type I receptors such as C. elegans daf-1 and Drosophila tkv show 38-53% identity in the same region. Some residues conserved in Drosophila and vertebrates are not present in the B. pahangi sequence. RT-PCR amplification has been used to show that the transcript is expressed in the three main stages of the B. pahangi life cycle: microfilariae, infective larvae and adults. The ligand remains unknown at this time but is likely to be most similar to that for C. elegans Q09488.


Asunto(s)
Brugia pahangi/genética , Genes de Helminto/genética , Proteínas Serina-Treonina Quinasas/genética , Receptores de Factores de Crecimiento Transformadores beta/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Brugia pahangi/crecimiento & desarrollo , Clonación Molecular , ADN Complementario/genética , ADN de Helmintos/genética , Regulación del Desarrollo de la Expresión Génica , Glicosilación , Proteínas del Helminto , Datos de Secuencia Molecular , Filogenia , ARN de Helminto/análisis , ARN Mensajero/análisis , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
16.
J Immunol Methods ; 196(1): 97-9, 1996 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-8841448

RESUMEN

A microcomputer software package for determining the concentration of either the antibody or antigen from ELISA data for IBM PC compatible is presented. In the program optical densities (OD) and fluorescence obtained from 96-well ELISA plate can be input either directly, by interfacing with different brands of microplate reader such as Multiskan II Plus and Organon Teknika to the computer or manually. This software utilizes some mathematical and statistical models to fit the standard curve of each assay and interpolate analyte concentration using data from OD or fluorescence measurements. Cubic spline (Guardabasso et al., 1988), bezier and polynomial (Rodbard, 1979; Baud et al., 1991) interpolation formulas can be used to fit the data over the entire range for estimating the antibody or antigen concentration of the unknown samples whose OD or fluorescence is beyond the entire range. This software package, based on the concentration values of the analyte determined in different fluids (Núnez et al., 1994; Morales et al., 1994) and with some rules and algorithms, is used to calculate the parameters of screening and diagnostic tests such as sensitivity, specificity and predictive values (Coughlin et al., 1992). With the construction of the Receiver Operating Characteristic (ROC) curve it is possible to analyse different values of the sensitivity and specificity of the screening and diagnostic tests. A comparative statistical test for two populations that are non-normally distributed using a non-parametric Mann-Whitney test is provided. This software is an expandable tool designed for general use in clinical and experimental applications, including diagnostic and screening tests.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Tamizaje Masivo/métodos , Programas Informáticos , Anticuerpos/análisis , Antígenos/análisis , Diagnóstico Diferencial , Humanos , Interfaz Usuario-Computador
17.
Mol Biochem Parasitol ; 118(1): 89-96, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11704277

RESUMEN

Several important nematode parasites have been found to express members of a gene family variously termed as venom allergen antigen homologue (vah) or Ancylostoma secreted protein (asp). In some cases these products are secreted by infective larval stages and have been suggested to be effective vaccine immunogens. We isolated the corresponding gene from the human filarial nematode, Brugia malayi, by first searching the expressed sequence tag (EST) dataset generated by the Filarial Genome Project and then using gene-specific nondegenerate primers matching the selected gene for PCR, from B. malayi cDNA libraries. We report here the full-length gene sequence, which we have designated as Bm-val-1, for vah/asp-like. The corresponding protein (Bm-VAL-1) contains 232 amino acids in a single homology unit, unlike products from some other species in which there is a tandem repeat. A putative signal sequence is present at the 5' end and there are two potential N-glycosylation sites. Murine antibodies to recombinant Bm-VAL-1 react with a 28 kDa protein in L3 extracts and recombinant Bm-VAL-1 is recognised by murine T cells primed with soluble L3 proteins. Of 82 ESTs corresponding to Bm-val-1, 72 are recorded from the infective larval (L3) stage. However, PCR on the first-strand cDNA from later mammalian stages revealed some expression at most subsequent time points. Over 95% (20/21) of microfilaraemic human filariasis patients are seropositive for antibodies to Bm-VAL-1, with particularly high levels of IgG3 and IgG4 isotypes. The IgG4 subclass may indicate stimulation by adult and/or microfilarial-derived immunogens. The association of Bm-VAL-1 with the infective stage and its recognition by humans exposed to filariasis suggests that further evaluation of this antigen as a vaccine candidate should be performed.


Asunto(s)
Alérgenos/genética , Brugia Malayi/inmunología , Proteínas del Helminto/genética , Proteínas del Helminto/inmunología , Venenos de Avispas/genética , Adulto , Secuencia de Aminoácidos , Animales , Anticuerpos Antihelmínticos/sangre , Anticuerpos Antihelmínticos/inmunología , Antígenos Helmínticos/genética , Antígenos Helmínticos/inmunología , Antígenos Helmínticos/metabolismo , Brugia Malayi/genética , Brugia Malayi/crecimiento & desarrollo , Brugia Malayi/metabolismo , Filariasis/inmunología , Filariasis/parasitología , Filariasis/prevención & control , Gerbillinae , Proteínas del Helminto/química , Proteínas del Helminto/metabolismo , Humanos , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Linfocitos T/inmunología , Vacunación , Vacunas/inmunología
18.
J Nucl Med ; 39(11): 1918-27, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9829584

RESUMEN

UNLABELLED: Radiolabeled antitumor antibodies hold promise for diagnostic imaging and therapy in oncology. The purpose of this study was to investigate the pharmacokinetics, clearances and possible differences of two dosage administrations of the 99mTc-labeled antiepidermal growth factor (EGF)-receptor antibody and to predict the best dose and schedule for future clinical evaluations of this radiopharmaceutical. METHODS: Nine patients (4 women, 5 men; mean age 46.4 +/- 14.0 yr) were administered 1-3 mg 99mTc-labeled anti-EGF-receptor antibody (a murine IgG2a isotype) by intravenous bolus infusion. After administration, blood samples were collected from 7 patients from an antecubital vein opposite to the injection side at intervals from 2 min to 24 hr after injection, and plasma samples were obtained for pharmacokinetic analysis. Appropriate plasma samples were examined for isotope clearance (i.e., microCi/ml at various intervals) and 99mTc complexation to plasma proteins by fast protein liquid chromatography (FPLC) analysis. Urine was collected from each patient at 3 hr intervals up to 24 hr after monoclonal antibody administration to monitor 99mTc clearance. Plasma time-activity curves were fitted to a two-compartment model using nonlinear least-squares regression analysis by the method of flexible polyhedrals. RESULTS: Plasma disappearance curves of 99mTc-labeled anti-EGF-receptor antibody were best fit by biexponential equation with a distribution half-life (t(1/2alpha)) of 0.137 +/- 0.076 hr (n = 7) and elimination half-life (t(1/2beta)) of 20.3 +/- 8.0 hr. Analysis of urine showed that activity clearance by this route amounted to 4.9% +/- 0.6% of the injected dose in 24 hr, and FPLC analysis showed no evidence of decomposition, only 6%-7% of 99mTc was in a low molecular weight species. CONCLUSION: Plasma pharmacokinetics and urine clearance indicate comparability in both doses. The pharmacokinetic properties of the 99mTc-labeled anti-EGF-receptor antibody were found to be dose-independent. These findings provide an initial characterization of the radiopharmaceutical disposition in patients and may be used as the basis for calculating a better estimate of biodistribution and dosimetry for patients who will receive 188Re-labeled anti-EGF-receptor antibody (MAb ior egf/r3) injection for radioimmunotherapy and warrants further controlled clinical trials to define the efficacy of the radiopharmaceutical.


Asunto(s)
Anticuerpos Monoclonales/farmacocinética , Receptores ErbB/inmunología , Neoplasias Pulmonares/diagnóstico por imagen , Radiofármacos/farmacocinética , Pertecnetato de Sodio Tc 99m/farmacocinética , Anticuerpos Monoclonales/administración & dosificación , Cromatografía Liquida , Femenino , Semivida , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Persona de Mediana Edad , Radioinmunodetección , Radioinmunoterapia , Radiometría , Radiofármacos/administración & dosificación , Pertecnetato de Sodio Tc 99m/administración & dosificación , Distribución Tisular
19.
J Nucl Med ; 39(1): 15-23, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9443731

RESUMEN

UNLABELLED: Accurate estimation of biodistribution and absorbed dose to normal organs and tumors is important for immunoscintigraphic studies and radioimmunotherapy treatment planning. METHODS: Four patients (3 men, 1 woman; mean age 54.8 +/- 9.2 yr; range 42-64 yr) were administered 3 mg of anti-human epidermal growth factor receptor (anti-hEGF-r) antibody (ior egf/r3), radiolabeled with 99mTc activity of 39.5 +/- 1.1 mCi (range 38.5 mCi-40.7 mCi) by intravenous bolus infusion. After administration, blood and urine samples were collected from three patients up to 24 hr after injection. Whole-body anterior and posterior scans were obtained at 5 min and 1, 3, 5 and 24 hr after injection. Using a computer program, regions of interest were drawn over the heart, liver, spleen, bladder and tumor to measure the activity in the source organs at each scanning time. Time-activity curves for each source organ were then fitted to monoexponential or biexponential functions by nonlinear least squares regression using the flexible polyhedrals method, which adequately fit our data with the correlation coefficient of 0.985 +/- 0.013, and were integrated to determine organ residence times. The mean absorbed doses to the whole body and various normal organs were then estimated from residence times and from blood and urine samples using the methods developed by the Medical Internal Radiation Dose Committee. The effective dose equivalent and effective dose were calculated as prescribed in ICRP Publication Nos. 30 and 60. RESULTS: Plasma disappearance curves of 99mTc-labeled anti-hEGF-r antibody were best-fit by a two-compartment model in all patients with a distribution half-life (t(1/2alpha)) of 0.207 hr +/- 0.059 hr (mean +/- s.d., n = 3) and an elimination half-life (t(1/2beta)) of 13.9 hr +/- 2.2 hr. Among the various organs, significant accumulation of the radiolabeled antibody was found in the liver (48.5% +/- 4.4%, mean +/- s.d.), heart (3.50% +/- 0.17%) and spleen (3.1% +/- 1.8%) at 5 min postadministration. These values were reduced to 3.2% +/- 0.4%, 0.1% +/- 0.01% and 0.1% +/- 0.1%, respectively, at 24 hr. Mean cumulative urinary excretion of 99mTc-labeled anti-hEGF-r antibody was 4.6% +/- 0.6% at 24 hr postinjection. Estimates of radiation absorbed dose to normal organs in rad/mCi administered (mean +/- s.d., n = 4) were: whole body 0.017 +/- 0.002; gallbladder wall 0.074 +/- 0.007; spleen 0.136 +/- 0.076; and liver 0.267 +/- 0.036. The effective dose equivalent and effective dose estimates for adults were 0.041 +/- 0.008 rem/mCi and 0.027 +/- 0.004 rem/mCi administered. CONCLUSION: This feasibility study indicates that 99mTc-labeled anti-hEGF-r antibody (ior egf/r3) can be used safely; this analysis provides a dosimetric framework for future studies. This monoclonal antibody, labeled with 188Re, could possibly permit a successful regional radioimmunotherapy of tumors of epithelial origin.


Asunto(s)
Receptores ErbB/inmunología , Radioinmunoterapia , Radiofármacos/uso terapéutico , Pertecnetato de Sodio Tc 99m/uso terapéutico , Adulto , Anticuerpos Monoclonales/farmacocinética , Anticuerpos Monoclonales/uso terapéutico , Estudios de Factibilidad , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , Masculino , Persona de Mediana Edad , Radioisótopos/farmacocinética , Radioisótopos/uso terapéutico , Radiometría , Cintigrafía , Radiofármacos/farmacocinética , Dosificación Radioterapéutica , Renio/farmacocinética , Renio/uso terapéutico , Pertecnetato de Sodio Tc 99m/farmacocinética , Distribución Tisular
20.
J Nucl Med ; 40(5): 768-75, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10319748

RESUMEN

UNLABELLED: Monoclonal antibody (moAb) ior egf/r3 is an IgG2a that recognizes the epidermal growth factor receptor (EGF-R). The aim of this study was to evaluate the diagnostic efficacy of the 99mTc-labeled moAb ior egf/r3 for the detection of epithelial-derived tumors, their metastases and recurrences. METHODS: One hundred forty-eight adult patients (51 women, 97 men; mean age 53 +/- 13 y) who were suspected of having cancer of epithelial origin were administered 3 mg/50 mCi (1.85 GBq) 99mTc-labeled moAb ior egf/r3 by intravenous bolus injection. Planar anterior and posterior images of the lesion sites and suspected metastases were acquired at 2, 4, 6 and 24 h after injection, and SPECT images were scanned at 5 h postinjection, using a 360 degrees circular orbit with 64 images. The backprojection method was used for image reconstruction with a Hamming-Hann filter. RESULTS: Labeling efficiency was always greater than 98.5% +/- 2.1 %. No adverse reactions or side effects were observed. Results of the biopsy specimens showed that 85.1% (126/148) of the patients had tumors of epithelial origin, 14.2% (21/148) were negative and 0.7% (1/148) had non-Hodgkin's lymphoma. The sensitivity rate by organ was as follows: brain (8/8, 100%), digestive tract (10/11, 90.9%), head and neck (17/23, 73.9%), lung (52/62, 83.9%) and breast (16/18, 88.9%). Overall sensitivity, specificity, accuracy, and positive and negative predictive values of the immunoscintigraphic imaging were 84.2% (106/126), 100.0% (22/22), 86.5% (128/148), 100% (106/106) and 52.4% (22/42), respectively. New metastases not identified previously by other diagnostic methods were detected in the 50% of the patients. CONCLUSION: Immunoscintigraphy with 99mTc-labeled moAb ior egf/r3 could be a useful procedure for the diagnosis and follow-up of the patients with tumors of epithelial origin.


Asunto(s)
Receptores ErbB/inmunología , Neoplasias Glandulares y Epiteliales/diagnóstico por imagen , Radioinmunodetección , Pertecnetato de Sodio Tc 99m , Animales , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Ratones , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Radiofármacos , Seguridad , Sensibilidad y Especificidad , Tomografía Computarizada de Emisión de Fotón Único
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