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1.
Genet Mol Res ; 14(4): 18799-807, 2015 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-26782530

RESUMEN

Assessments of chromosomal integrity and structure enable the prevention of diseases associated with the work environment, with the frequencies of chromosomal aberrations and micronuclei often being used as markers in biomonitoring. Owing to their routine manipulation of potentially toxic chemicals, tannery workers as a group merit a more thorough evaluation and discussion. This study investigated chromosomal damage in 30 workers from a tannery in the city of Teresina, the state capital of Piauí, northeast Brazil, and a control group consisting of 30 employees from a nearby accounting firm. The frequencies of chromosomal aberrations (CAs) and binucleated cell micronuclei (MN) were assessed as a measure of damage. Means were compared using the Student t-test and ANOVA-Dunnett test. Our results indicated a higher number of CAs in exposed individuals compared to the control group, including dicentric (P < 0.0001) and tricentric chromosomes (P < 0.001), and those in ring (P < 0.0001) and acentric ring forms (P < 0.001). Assessment of MN frequency demonstrated a similar trend (exposed vs control, P < 0.0001). It was concluded that the tannery workers in this study exhibited a higher incidence of genetic damage than comparable unexposed individuals. However, further research on this subject is needed, particularly in regard to potentially clastogenic agents used in the tanning process.


Asunto(s)
Aberraciones Cromosómicas/efectos de los fármacos , Mutágenos/toxicidad , Exposición Profesional , Curtiembre , Adolescente , Adulto , Anciano , Brasil , Estudios de Casos y Controles , Análisis Citogenético , Femenino , Humanos , Masculino , Micronúcleos con Defecto Cromosómico , Pruebas de Micronúcleos , Persona de Mediana Edad
2.
Tissue Antigens ; 81(4): 194-203, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23510415

RESUMEN

We have updated the catalogue of common and well-documented (CWD) human leukocyte antigen (HLA) alleles to reflect current understanding of the prevalence of specific allele sequences. The original CWD catalogue designated 721 alleles at the HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQA1, -DQB1, and -DPB1 loci in IMGT (IMmunoGeneTics)/HLA Database release 2.15.0 as being CWD. The updated CWD catalogue designates 1122 alleles at the HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQA1, -DQB1, -DPA1 and -DPB1 loci as being CWD, and represents 14.3% of the HLA alleles in IMGT/HLA Database release 3.9.0. In particular, we identified 415 of these alleles as being 'common' (having known frequencies) and 707 as being 'well-documented' on the basis of ~140,000 sequence-based typing observations and available HLA haplotype data. Using these allele prevalence data, we have also assigned CWD status to specific G and P designations. We identified 147/151 G groups and 290/415 P groups as being CWD. The CWD catalogue will be updated on a regular basis moving forward, and will incorporate changes to the IMGT/HLA Database as well as empirical data from the histocompatibility and immunogenetics community. This version 2.0.0 of the CWD catalogue is available online at cwd.immunogenomics.org, and will be integrated into the Allele Frequencies Net Database, the IMGT/HLA Database and National Marrow Donor Program's bioinformatics web pages.


Asunto(s)
Alelos , Antígenos HLA/clasificación , Antígenos HLA/inmunología , Histocompatibilidad/inmunología , Bases de Datos Genéticas , Frecuencia de los Genes , Sitios Genéticos/inmunología , Genética de Población , Antígenos HLA/genética , Histocompatibilidad/genética , Prueba de Histocompatibilidad , Humanos , Terminología como Asunto
3.
Sci Rep ; 10(1): 4749, 2020 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-32179816

RESUMEN

Living cells are constantly exchanging momentum with their surroundings. So far, there is no consensus regarding how cells respond to such external stimuli, although it reveals much about their internal structures, motility as well as the emergence of disorders. Here, we report that twelve cell lines, ranging from healthy fibroblasts to cancer cells, hold a ubiquitous double power-law viscoelastic relaxation compatible with the fractional Kelvin-Voigt viscoelastic model. Atomic Force Microscopy measurements in time domain were employed to determine the mechanical parameters, namely, the fast and slow relaxation exponents, the crossover timescale between power law regimes, and the cell stiffness. These cell-dependent quantities show strong correlation with their collective migration and invasiveness properties. Beyond that, the crossover timescale sets the fastest timescale for cells to perform their biological functions.


Asunto(s)
Fenómenos Fisiológicos Celulares/fisiología , Elasticidad , Viscosidad , Línea Celular , Línea Celular Tumoral , Movimiento Celular , Fibroblastos/fisiología , Humanos , Microscopía de Fuerza Atómica , Modelos Biológicos , Imagen Molecular , Invasividad Neoplásica/patología
4.
Tissue Antigens ; 74(6): 480-5, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19793314

RESUMEN

A project of the 15th International Histocompatibility Workshop examined the rarity of human leukocyte antigen (HLA) alleles. A section was constructed in the website, www.allelefrequencies.net to contain this data from different sources. A mechanism to search the data was implemented for use by any individual.


Asunto(s)
Alelos , Biología Computacional , Antígenos HLA/genética , Bases de Datos Factuales , Humanos
5.
J Clin Invest ; 105(2): 207-13, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10642599

RESUMEN

Fogo selvagem (FS), the endemic form of pemphigus foliaceus, is a cutaneous autoimmune disease characterized by subcorneal blistering of the epidermis and the production of autoantibodies against the desmosomal antigen desmoglein-1 (Dsg1). Previously, we showed that mice injected with autoantibodies from FS patients develop a skin disease that reproduces the clinical, histological, and immunological features of FS, indicating that autoantibodies play an essential role in the development of this disease. The purpose of this study was to characterize the autoimmune T-cell response associated with FS. We provide here the first evidence, to our knowledge, that the great majority of FS patients have circulating T lymphocytes that specifically proliferate in response to the extracellular domain of Dsg1. Long-term T cells developed from these patients also responded to Dsg1, and this antigen-specific response was shown to be restricted to HLA-DR molecules. These Dsg1-reactive FS T cells exhibited a CD4-positive memory T-cell phenotype and produced a T helper 2-like cytokine profile. These findings represent the initial steps in defining the role of T cells in FS autoimmunity.


Asunto(s)
Autoantígenos/inmunología , Cadherinas/inmunología , Pénfigo/inmunología , Linfocitos T/inmunología , Adolescente , Adulto , Anciano , Antígenos CD/biosíntesis , Autoantígenos/genética , Cadherinas/genética , Células Clonales/citología , Células Clonales/inmunología , Citocinas/biosíntesis , Desmogleína 1 , Epítopos/genética , Epítopos/inmunología , Femenino , Citometría de Flujo , Genes MHC Clase II/genética , Prueba de Histocompatibilidad , Humanos , Inmunofenotipificación , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Receptores de Antígenos de Linfocitos T alfa-beta/biosíntesis , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Linfocitos T/citología
6.
Braz J Med Biol Res ; 39(9): 1241-7, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16981050

RESUMEN

Third molar extraction is a common procedure frequently accompanied by moderate or severe pain, and involves sufficient numbers of patients to make studies relatively easy to perform. The aim of the present study was to determine the efficacy and safety of the therapeutic combination of 10 mg piroxicam, 1 mg dexamethasone, 35 mg orphenadrine citrate, and 2.5 mg cyanocobalamin (Rheumazin) when compared with 20 mg piroxicam alone (Feldene) in mandibular third molar surgery. Eighty patients scheduled for removal of the third molar were included in this randomized and double-blind study. They received (vo) Rheumazin or Feldene 30 min after tooth extraction and once daily for 4 consecutive days. Pain was determined by a visual analogue scale and by the need for escape analgesia (paracetamol). Facial swelling was evaluated with a measuring tape and adverse effects and patient satisfaction were recorded. There was no statistically significant difference in facial swelling between Rheumazin and Feldene (control group). Both drugs were equally effective in the control of pain, with Rheumazin displaying less adverse effects than Feldene. Therefore, Rheumazin appears to provide a better risk/benefit ratio in the mandibular molar surgery. Since the side effects resulting from nonsteroidal anti-inflammatory drug administration are a severe limitation to the routine use of these drugs in clinical practice, our results suggest that Rheumazin can be a good choice for third molar removal treatment.


Asunto(s)
Antiinflamatorios/administración & dosificación , Tercer Molar/cirugía , Relajantes Musculares Centrales/administración & dosificación , Extracción Dental , Complejo Vitamínico B/administración & dosificación , Adolescente , Adulto , Antiinflamatorios/efectos adversos , Dexametasona/administración & dosificación , Dexametasona/efectos adversos , Método Doble Ciego , Quimioterapia Combinada , Edema/prevención & control , Femenino , Humanos , Masculino , Persona de Mediana Edad , Relajantes Musculares Centrales/efectos adversos , Orfenadrina/administración & dosificación , Orfenadrina/efectos adversos , Dimensión del Dolor , Dolor Postoperatorio/tratamiento farmacológico , Piroxicam/administración & dosificación , Piroxicam/efectos adversos , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Vitamina B 12/administración & dosificación , Vitamina B 12/efectos adversos , Complejo Vitamínico B/efectos adversos
7.
Braz J Biol ; 76(3): 600-10, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27097084

RESUMEN

This study aims to evaluate the environmental factors determining of the changes in phytoplankton structure in spatial (upper, middle and lower course) and seasonal (dry and rainy period) scales in a eutrophic river (Almada River, northeastern Brazil). In the study period, total accumulated rainfall was below of the historic average, resulting in flow reduction, mainly in rainy period. High orthophosphate concentration was found at the sampling sites. Phytoplankton chlorophyll a increased from upstream to downstream. Geitlerinema splendidum (S1) and Chlamydomonas sp. (X2) were the most abundant species in the upper course and several species of diatoms (D), Euglenophyceae (W1, W2) and Chlorophyceae (X1) in the middle and lower course. The functional groups were found to be characteristic of lotic ecosystem, shallow, with low light availability, rich in organic matter and eutrophic environments. We conclude that phytoplankton community structure was sensitive to change of the river flow and nutrient availability in spatial and seasonal scale in a tropical river.


Asunto(s)
Monitoreo del Ambiente/métodos , Fitoplancton/crecimiento & desarrollo , Ríos , Análisis Espacio-Temporal , Clima Tropical , Biodiversidad , Brasil , Clorofila , Clorofila A , Diatomeas , Ecosistema , Lluvia , Estaciones del Año
8.
Int J Impot Res ; 17(1): 27-32, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15510188

RESUMEN

To investigate the pharmacodynamics of phentolamine in human corpus cavernosum (HCC) with special attention to the role of the K+ channels. Strips of HCC precontracted with nonadrenergic stimuli and kept in isometric organ bath immersed in a modified Krebs-Henseleit solution enriched with guanethidine and indomethacine were used in order to study the mechanism of the phentolamine-induced relaxation. Phentolamine caused relaxation (approximately 50%) in HCC strips precontracted with K+ 40 mM. This effect was not blocked by tetrodotoxin (1 microM) (54.6+/-4.6 vs 48.9+/-6.4%) or (atropine (10 microM) (52.7+/-6.5 vs 58.6+/-5.6%). However, this relaxation was significantly attenuated by L-NAME (100 microM) (59.7+/-5.8 vs 27.8+/-7.1%; P<0.05; n = 8) and ODQ (100 microM) (62.7+/-5.1 vs 26.8+/-3.9%; P<0.05; n = 8). Charybdotoxin and apamin (K(Ca)-channel blockers) did not affect the phentolamine relaxations (54.6+/-4.6 vs 59.3+/-5.2%). Glibenclamide (100 microM), an inhibitor of K(ATP)-channel, caused a significant inhibition (56.7+/-6.3 vs 11.3+/-2.3%; P<0.05; n = 8) of the phentolamine-induced relaxation. In addition, the association of glibenclamide and L-NAME almost abolished the phentolamine-mediated relaxation (54.6+/-5.6 vs 5.7+/-1.4%; P<0.05; n = 8). The results suggest that phentolamine relaxes HCC by a nonadrenergic-noncholinergic mechanism dependent on nitric oxide synthase activity and activation of K(ATP)-channel.


Asunto(s)
Antagonistas Adrenérgicos alfa/farmacología , Sistema Nervioso Autónomo/efectos de los fármacos , Proteínas de la Membrana/efectos de los fármacos , Pene/efectos de los fármacos , Fentolamina/farmacología , Adulto , GMP Cíclico/metabolismo , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Humanos , Técnicas In Vitro , Contracción Isométrica/efectos de los fármacos , Masculino , Contracción Muscular/efectos de los fármacos , Relajación Muscular/efectos de los fármacos , Óxido Nítrico/fisiología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo III , Fentolamina/antagonistas & inhibidores , Canales de Potasio , Cloruro de Potasio/farmacología
9.
Braz J Biol ; 65(2): 299-304, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-16097733

RESUMEN

The yeast species found in necrotic stems of three columnar cacti (Pilosocereus machrisii, Pilosocereus vilaboensis, and Praecereus euchlorus) at eight localities in Brazil were described and a similarity analysis using Sorensen distances was used to compare the composition of yeast species at these localities. Of 56 necrotic cactus stems sampled, 32 produced yeast colonies. Ten species of yeast or yeast-like microorganisms were identified from 53 isolates, with Pichia cactophila, Candida sonorensis, Geotrichum sp., and Sporopachydermia cereana being the most common. The remaining species occurred in low proportions in the cacti surveyed. The similarity analysis provided a dendogram (UPGMA) that clustered the yeast communities from different cactus species and indicated that host cactus species was unimportant in this clustering.


Asunto(s)
Cactaceae/microbiología , Enfermedades de las Plantas/microbiología , Levaduras/aislamiento & purificación , Animales , Brasil , Necrosis
10.
J Hum Hypertens ; 29(6): 366-72, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25339292

RESUMEN

The pathophysiological mechanisms of arterial hypertension during hemodialysis (HD) in patients with end-stage renal disease (ESRD) are still poorly understood. The aim of this study is to investigate physiological, cardiovascular and neuroendocrine changes in patients with ESRD and its correlation with changes in blood pressure (BP) during the HD session. The present study included 21 patients with ESRD undergoing chronic HD treatment. Group A (study) consisted of patients who had BP increase and group B (control) consisted of those who had BP reduction during HD session. Echocardiograms were performed during the HD session to evaluate cardiac output (CO) and systemic vascular resistance (SVR). Before and after the HD session, blood samples were collected to measure brain natriuretic peptide (BNP), catecholamines, endothelin-1 (ET-1), nitric oxide (NO), electrolytes, hematocrit, albumin and nitrogen substances. The mean age of the studied patients was 43 ± 4.9 years, and 54.6% were males. SVR significantly increased in group A (P<0.001). There were no differences in the values of BNP, NO, adrenalin, dopamin and noradrenalin, before and after dialysis, between the two groups. The mean value of ET-1, post HD, was 25.9 pg ml(-1) in group A and 13.3 pg ml(-1) in group B (P = < 0.001). Patients with ESRD showed different hemodynamic patterns during the HD session, with significant BP increase in group A, caused by an increase in SVR possibly due to endothelial dysfunction, evidenced by an increase in serum ET-1 levels.


Asunto(s)
Hipertensión/fisiopatología , Diálisis Renal , Adulto , Anciano , Presión Sanguínea , Gasto Cardíaco , Endotelina-1/sangre , Femenino , Humanos , Hipertensión/sangre , Masculino , Persona de Mediana Edad , Neurotransmisores/sangre , Óxido Nítrico/fisiología , Resistencia Vascular
11.
J Invest Dermatol ; 107(1): 68-75, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8752842

RESUMEN

Fogo Selvagem (FS) is an autoimmune disease characterized by subcorneal vesicles and antidesmoglein-1 autoantibodies. Previous epidemiologic data have linked the onset of FS to exposure to an environmental antigen(s). This investigation describes a unique human settlement with an extraordinarily high prevalence of FS. This community is made up of Amerindians belonging to the Terena tribe, which has settled on the Limao Verde reservation in the state of Mato Grosso do Sul in Brazil. Twenty-six well-characterized FS cases have been identified within a total population of 998, yielding a prevalence of 2.6%. Seventeen of the patients (65 %) were males, and over 50% were older than 30 y of age. The incidence of the disease shows temporal periodicity, i.e., years with several cases of FS alternating with years with no cases. Over one-half of the cases occurred in genetically related family members. Another Terena reservation, the Ipegue/Taunay, located 90 km west of the Limao Verde reservation, was also evaluated as a control group. This reservation, with a population of 2203, had no recorded cases of FS. Thus, the Limao Verde reservation represents a new focus of FS in which the disease exhibits temporal, geographic, and familial clustering. These results suggest that the environmental antigen or antigens precipitating FS are endemic to the Limao Verde reservation. This reservation appears to be an ideal population for carrying out sero-epidemiologic, genetic, and environmental studies aimed at disclosing the etiology of FS.


Asunto(s)
Enfermedades Autoinmunes/epidemiología , Indígenas Sudamericanos , Pénfigo/epidemiología , Adolescente , Adulto , Anciano , Autoanticuerpos/análisis , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/inmunología , Brasil , Niño , Análisis por Conglomerados , Epidermis/inmunología , Femenino , Humanos , Indígenas Sudamericanos/genética , Masculino , Persona de Mediana Edad , Linaje , Pénfigo/genética , Pénfigo/inmunología , Prevalencia , Factores de Tiempo
12.
Transplantation ; 51(2): 370-3, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1994530

RESUMEN

We have previously observed that transplant recipient sera with endothelial antibodies are bound to epidermal cells, as shown by immunofluorescence on sections of skin. It was also reported that early kidney failures that occurred despite negative T cell crossmatches were associated with, and could have been predicted by, a crossmatch with donor skin. Ninety patients undergoing kidney transplantation have now been evaluated using this technique. A few other patients were excluded from the analysis because of the presence of autoantibodies staining autologous skin. In 12 the crossmatch with donor skin was positive, and 9 of them had severe rejection within the first 10 days after transplantation. The three patients with a positive skin crossmatch and a benign course had not been tested with autologous skin and therefore autoantibodies could not be excluded. Only 7 of the 78 patients with negative skin crossmatches had early rejection. The correlation between skin crossmatch and early rejection was statistically highly significant (P less than 0.0001). Studies by flow cytometry have shown that these antigens are found on the surface of epidermal and endothelial cells, and are modulated by gamma interferon. When tested against a panel of skin donors, skin alloantibodies gave different patterns of positive and negative reactions, suggesting polymorphism.


Asunto(s)
Prueba de Histocompatibilidad/métodos , Trasplante de Riñón/inmunología , Antígenos de Superficie/análisis , Endotelio/inmunología , Epidermis/inmunología , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Rechazo de Injerto , Humanos , Isoantígenos/análisis , Donantes de Tejidos
13.
Hum Immunol ; 30(1): 60-8, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2001976

RESUMEN

The second exon of HLA-DPB includes five polymorphic segments with extensive sharing of sequences between alleles. In order to facilitate assignment of specificities in heterozygous individuals, we have used group-specific amplification of two nonoverlapping sets of DPB alleles (here called group A and group B) with especially designed primers. Group A and group B polymerase chain reaction products were hybridized with sequence-specific oligonucleotide probes generating easily recognizable patterns which defined 24 distinct HLA-DPB alleles. We also established a routine procedure for distinguishing HLA-DP homozygosity from failed amplification in one of the alleles. Our results showed that when only one allele was detected, failure of amplification had occurred in less than 4% of the cases. DNA typing with this method correlated well with primed-lymphocyte typing for HLA-DP in the Tenth Workshop, as determined by us in assays performed on the workshop B-cell lines. Two normal panels of unrelated subjects were tested to obtain population frequencies. We conclude that this method is simple, relatively quick, and accurate. It is the method of choice for studies to determine the role of HLA-DP alleles in T cell reactions, in various diseases, and in transplantation.


Asunto(s)
ADN/genética , Antígenos HLA-DP/genética , Prueba de Histocompatibilidad/métodos , Alelos , Linfocitos B/inmunología , Secuencia de Bases , Línea Celular , Sondas de ADN , Amplificación de Genes , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa
14.
Hum Immunol ; 31(2): 139-44, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2066273

RESUMEN

In this study we present an approach for the definition of the alleles belonging to the HLA-DR2 group by DNA typing with oligonucleotide probes. Following methodology similar to that we used previously for the definition of other HLA-DR subsets, we have now developed primers for DR2-DRB1 and DR2-DRB5 amplification, and probes for the identification of sequences that distinguish the subtypes of this group of genes. The method used defines all the previously described alleles at both DR2-associated DRB loci. In addition, we have identified a variant of DRB1-DR2-Dw2. This new allele has been called DRB1*15.3. It is different from DRB1*1501 in codon 30, where it carries histidine instead of tyrosine. Eight different haplotype combinations of DRB5, DRB1, and DQB1 were identified within the DR2 group and their occurrence in four normal panels of different ethnic origin has been described. Haplotypes containing DRB1*15.3 occurred most frequently in black panel members in whom it was associated with either DQB1*0602 or DQB1*0501. Two unusual haplotypes were observed: one containing elements of DR2-Dw21 (DQB1*0502) and of DR2-Dw22 (DRB1*1602) and one containing elements of Dw21 (DRB1*1601, DQB1*0502) and Dw2 (DRB5*0101). The methods described permit simple and rapid determination of the alleles of the HLA-DR2 group and should be useful for population studies and for investigation of DR2-associated diseases.


Asunto(s)
Alelos , Antígeno HLA-DR2/genética , Antígenos de Histocompatibilidad Clase II/genética , Secuencia de Aminoácidos , Secuencia de Bases , Mapeo Cromosómico , Electroforesis en Gel de Agar , Haplotipos , Humanos , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Sondas de Oligonucleótidos , Reacción en Cadena de la Polimerasa
15.
Hum Immunol ; 60(11): 1138-49, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10600013

RESUMEN

We have studied the HLA alleles of 60 unrelated healthy Terena and 10 Terena families. They are members of an isolated Brazilian tribe located in Mato Grosso do Sul (South Central Brazil). Six novel alleles were found in this population: HLA-A*0219 (gf = 0.02), A*0222 (gf = 0.15), HLA-B* 3520 (gf = 0.01), B*3521 (gf = 0.03), B*3912 (gf = 0.03) and B*4803 (gf = 0.16). Five of the six novel alleles differ from their putative progenitors by amino acid replacements in residues that contribute to the pockets of the peptide-binding site. Many of the variants defined by molecular methods were not identified correctly by serological typing. We calculated heterozygosity values (H) for HLA-A, -B, -C, DRB1, DQB1 and DPB . The highest values were observed at the HLA-B locus, followed by HLA-A, -DRB1 and DQB1. Residue positions 9, 24, 45, 62, 67, 95, 114, 116, 156, and 163 of HLA class I showed heterozygosity values greater than 0.50. Nine of them contribute to the peptide-binding specificity pockets and one to the T cell receptor binding site. If HLA antigens are useful for defense against pathogenic agents, heterozygosity would offer an advantage by allowing binding of a larger repertoire of peptides to the class I molecules. Individuals that are heterozygous at these positions would probably have a wider repertoire of peptide presentation to T cells. The observed results including the presence of novel alleles in the class I HLA loci suggest a functionally significant, more rapid evolution of class I compared to class II loci in this South American isolated population.


Asunto(s)
Evolución Molecular , Genes MHC Clase II , Genes MHC Clase I , Antígenos HLA/genética , Indígenas Sudamericanos/genética , Polimorfismo Genético , Alelos , Secuencia de Bases , Brasil , Cartilla de ADN/genética , Emigración e Inmigración , Frecuencia de los Genes , Haplotipos , Heterocigoto , Humanos
16.
Bone Marrow Transplant ; 19(3): 299-300, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9028563

RESUMEN

The Brazilian unrelated bone marrow donor program began in 1993 and an unrelated matched donor was found for a Fanconi anemia patient without a sibling match. An 11-year-old female recipient received FTBI (6.0 Gy) and cyclophosphamide (40 mg/kg) as conditioning. The 41-year-old female unrelated donor received G-CSF at 5 micrograms/kg x 5 days, and on day 6 and 7 postmobilization, peripheral blood stem cells were harvested. Engraftment was seen on day 19 post-BMT and she remains alive and well on day 191+. This case supports the potential role of harvesting G-CSF-stimulated PBSC for unrelated bone marrow transplantation.


Asunto(s)
Anemia de Fanconi/terapia , Trasplante de Células Madre Hematopoyéticas , Niño , Femenino , Prueba de Histocompatibilidad , Humanos , Trasplante Homólogo
17.
J Clin Pharmacol ; 39(10): 1053-61, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10516940

RESUMEN

In this study, the authors assessed the bioequivalence of two fluoxetine tablet formulations in 24 healthy volunteers of both sexes who received a single 20 mg dose of each fluoxetine formulation, and a new sensitive method for the quantification of fluoxetine and norfluoxetine in human plasma was developed. The study was conducted using an open, randomized, two-period crossover design with a 4-week washout interval. Plasma samples were obtained over a 672-hour period. Plasma fluoxetine and norfluoxetine concentrations were analyzed by combined liquid chromatography coupled to mass spectrometry (LC-MS) with positive ion electrospray ionization using selected ion recording (SIR). Kolmogorov-Smirnov's test, histograms, probit plots, and the correlation between norfluoxetine AUC(0-infinity) and fluoxetine AUC(0-infinity) were used to analyze the population distribution. The limit of quantification was 0.15 ng.ml-1 and 0.50 ng.ml-1 for both fluoxetine and norfluoxetine, respectively. Within- and between-run imprecision was less than 13% and 17%, respectively. The pharmacokinetic parameters obtained for fluoxetine and norfluoxetine after the administration of each formulation included AUC(0-672 h), AUC(0-infinity), Cmax, Cmax/AUC(0-672 h), tmax, t1/2, and Ke. The AUC values for fluoxetine were not consistent with a normal distribution, reflecting the existence of two different populations (poor and extensive metabolizers). The mean pharmacokinetic parameters for extensive fluoxetine metabolizers were 27.0 ng ml-1 for Cmax, 2064.0 ng h ml-1 for AUC(0-infinity), and 85.4 h t1/2. The mean pharmacokinetic parameters for norfluoxetine (in extensive metabolizers only) were 2532.0 ng h ml-1 for AUC(0-infinity) and 8.4 ng ml-1 for Cmax. For fluoxetine bioequivalence, the 90% CI of the individual ratio geometric mean for Psiquial/Prozac (including both extensive and poor metabolizers) was 101.6% to 121.1% for AUC(0-672 h) and 86.1% to 102.6% for Cmax. For norfluoxetine, the 90% CI of the individual ratio geometric mean for Psiquial/Prozac (including both extensive and poor metabolizers) was 90.3% to 108.3% for AUC(0-672 h) and 84.5% to 106.3% for Cmax. The new method developed (LC-MS) presented high sensitivity, specificity, and short chromatographic run for the quantification of both fluoxetine and norfluoxetine in human plasma. Since both 90% CI for AUC and Cmax geometric mean ratios were included in the 80% to 125% interval proposed by the U.S. Food and Drug Administration, Psiquial was considered bioequivalent to Prozac according to both the rate and extent of absorption. The finding that there were no significant differences in the bioequivalence assessed by either fluoxetine or norfluoxetine pharmacokinetic parameters indicates that future bioequivalence trials may be performed by quantifying fluoxetine only.


Asunto(s)
Fluoxetina/farmacocinética , Inhibidores Selectivos de la Recaptación de Serotonina/farmacocinética , Adolescente , Adulto , Área Bajo la Curva , Cromatografía Liquida , Estudios Cruzados , Interpretación Estadística de Datos , Femenino , Fluoxetina/análogos & derivados , Fluoxetina/sangre , Humanos , Masculino , Espectrometría de Masas , Comprimidos , Equivalencia Terapéutica
18.
J Mass Spectrom ; 35(3): 440-5, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10767775

RESUMEN

A liquid chromatographic atmospheric pressure chemical ionization tandem mass spectrometric method is described for the determination of 21-hydroxydeflazacort in human plasma using dexamethasone 21-acetate as an internal standard. The procedure requires a single diethyl ether extraction. After evaporation of the solvent under a nitrogen flow, the analytes are reconstituted in the mobile phase, chromatographed on a C18 reversed-phase column and analyzed by mass spectrometry via a heated nebulizer interface where they are detected by multiple reaction monitoring. The method has a chromatographic run time of less than 5 min and a linear calibration curve with a range of 1-400 ng ml(-1) (r>0.999). The between-run precision, based on the relative standard deviation for replicate quality controls, was < or =5.5% (10 ng ml(-1)), 1.0% (50 ng ml(-1)) and 2.7% (200 ng ml(-1)). The between-run accuracy was +/-7.1, 3.8 and 4.8% for the above concentrations, respectively. This method was employed in a bioequivalence study of two DFZ tablet formulations (Denacen from Marjan Industria e Comercio, Brazil, as a test formulation, and Calcort from Merrell Lepetit, Brazil, as a reference formulation) in 24 healthy volunteers of both sexes who received a single 30 mg dose of each formulation. The study was conducted using an open, randomized, two-period crossover design with a 7-day washout interval. The 90% confidence interval (CI) of the individual geometric mean ratio for Denacen/Calcort was 89.8-109.5% for area under the curve AUC(0-24 h) and 80.7-98.5% for Cmax. Since both the 90% CI for AUC(0-24 h) and Cmax were included in the 80-125% interval proposed by the US Food and Drug Administration, Denacen was considered bioequivalent to Calcort according to both the rate and extent of absorption.


Asunto(s)
Análisis Químico de la Sangre/métodos , Inmunosupresores/sangre , Espectrometría de Masas/métodos , Pregnenodionas/sangre , Adolescente , Adulto , Presión Atmosférica , Análisis Químico de la Sangre/normas , Cromatografía Líquida de Alta Presión/métodos , Femenino , Humanos , Inmunosupresores/farmacocinética , Inmunosupresores/normas , Masculino , Espectrometría de Masas/normas , Pregnenodionas/farmacocinética , Pregnenodionas/normas , Control de Calidad , Estándares de Referencia , Equivalencia Terapéutica
19.
J Mass Spectrom ; 36(2): 188-94, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11288201

RESUMEN

A rapid, sensitive and specific analytical method was developed and validated to quantify gabapentin in human plasma using acetaminophen as an internal standard. The method employs a single plasma protein precipitation. The analytes are chromatographed on a C4 reversed-phase chromatographic column and analyzed by mass spectrometry in the multiple reaction monitoring (MRM) mode. The method has a chromatographic run time of 4 min and a linear calibration curve over the range 50-10 000 ng x ml(-1) (r > 0.999). The between-run precision, based on the relative standard deviation for replicate quality controls, was < or = 4.8 % (200 ng x ml(-1)), 6.0% (1000 ng x ml(-1)) and 4.4% (5000 ng x ml(-1)). The between-run accuracy was +/-2.6, 4.4 and 0.5% for the above-mentioned concentrations, respectively. This method was employed in a bioequivalence study of two gabentin capsule formulations (Progresse from Biosintética, Brazil, as a test formulation, and Neurotin from Parke-Davis, as a reference formulation) in 24 healthy volunteers of both sexes who received a single 300 mg dose of each formulation. The study was conducted using an open, randomized, two-period crossover design with a 7-day washout interval. The 90% confidence interval (CI) of the individual ratio geometric mean for Progresse/Neurotin was 87.9-115.6% for AUC(0-36 h) and 88.6-111.7% for Cmax. Since both 90% CI for AUC(0-36 h) and Cmax were included in the 80-125% interval proposed by the US Food and Drug Administration, Progresse was considered bioequivalent to Neurotin according to both the rate and extent of absorption.


Asunto(s)
Acetatos/sangre , Acetatos/química , Aminas , Ácidos Ciclohexanocarboxílicos , Ácido gamma-Aminobutírico , Cromatografía Líquida de Alta Presión , Gabapentina , Humanos , Espectrometría de Masa por Ionización de Electrospray
20.
Clin Lab Med ; 11(3): 621-32, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1934967

RESUMEN

This article summarizes work that focuses on alloantibodies that bind to endothelial cells and attempts to provide an evaluation of the apparent role that antigens distinct from classic HLA alleles, and not expressed in lymphocytes, may play in kidney transplant rejection. The most recent experience with the donor-skin crossmatch in prediction of early kidney allograft rejection also is described.


Asunto(s)
Isoanticuerpos , Antígenos de Histocompatibilidad Menor , Inmunología del Trasplante , Endotelio Vascular/inmunología , Rechazo de Injerto/inmunología , Prueba de Histocompatibilidad , Humanos , Monocitos/inmunología , Piel/inmunología
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