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1.
Allergy ; 73(12): 2342-2351, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29777594

RESUMEN

BACKGROUND: Basophils are commonly associated with allergic responses because of their ability to produce large amounts of pro-Th2 cytokines and histamine. However, the mechanisms through which bone marrow-resident basophils (BMRB) become fully competent cytokine and histamine producers in response to IgE crosslinking are poorly understood. Here, we sought to determine the role of IL-3 in promoting pro-Th2 basophils. METHODS: BMRB and basophils exposed to IL-3 in vitro and in vivo were evaluated for their production of Th2 cytokines and histamine in response to FcεRI crosslinking on both protein and gene expression levels. In vivo relevance of our findings was assessed in a model of ovalbumin-induced allergic asthma using IL-3-deficient and wild-type mice in a protocol of adoptive basophil transfer. RESULTS: We show that BMRB and basophils previously exposed to IL-3 differ in their ability to generate cytokines (IL-4, IL-6, IL-13, and GM-CSF) and histamine in response to FcεRI crosslinking, reflecting two stages of maturation. Exposure to IL-3 initiated an autocrine loop of endogenous IL-3 production that enhanced histamine and cytokine production upon FcεRI crosslinking. This increased responsiveness required calcium flux and was dependent on calcineurin and store-operated calcium channels. Our findings are of pathophysiological relevance, as assessed by the failure of IL-3-deficient mice to develop airway hyperreactivity, which could be restored by adoptive transfer of IL-3-derived basophils recovered from wild-type mice. CONCLUSION: IL-3-dependent basophils promote Th2 allergic AHR, which designates the IL-3/basophil axis as a promising therapeutic target for the treatment of basophil-dependent asthma.


Asunto(s)
Interleucina-3/inmunología , Hipersensibilidad Respiratoria/etiología , Animales , Basófilos , Células de la Médula Ósea , Citocinas/metabolismo , Histamina/metabolismo , Inflamación/patología , Ratones , Hipersensibilidad Respiratoria/patología , Células Th2/inmunología , Células Th2/fisiología
2.
Genet Mol Res ; 14(4): 17472-81, 2015 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-26782390

RESUMEN

Biflorin is an o-naphthoquinone isolated from the roots of the plant Capraria biflora L. (Scrophulariaceae). In this study, the cytotoxic effects of biflorin were verified, and late apoptosis was detected in various cancer cell lines by in situ analysis. The cytotoxicity was further evaluated exclusively for 48 h of treatment in different tumor and non-tumor cell lines (Hep-2, HeLa, HT-29, A-375, and A-549, and HEK-293, respectively). The results indicated that biflorin induced selective cytotoxicity in tumor cells. HeLa cells were more susceptible to biflorin, followed by HT-29, A-549, A-375, and Hep-2 at all concentrations (range 5-50 µg/mL), and the highest half-maximal inhibitory concentration IC50 (56.01 ± 1.17 µg/mL) was observed in HEK-293 cells. Late apoptotic/necrotic events, observed by in situ immunostaining with Annexin V, varied with each cell line; an increase in late apoptotic events was observed corresponding to the increase in biflorin dosage. Hep-2 cells showed a greater percentage of late apoptotic events among the tumor cell lines when treated with higher concentrations of biflorin (69.63 ± 2.28%). The non-tumor HEK-293 line showed greater resistance to late apoptotic events, as well as a lower level of cytotoxicity (77.69 ± 6.68%) than the tested tumor lines. The data presented indicate that biflorin showed an important, possibly selective, cytotoxicity against tumor cell lines, thereby revealing a promising novel substance with potential anticancer activity for tumor therapy.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Naftoquinonas/administración & dosificación , Neoplasias/tratamiento farmacológico , Antineoplásicos Fitogénicos/química , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Células HEK293 , Humanos , Naftoquinonas/química , Neoplasias/patología , Scrophulariaceae/química
3.
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
4.
Sex Transm Infect ; 90(5): 434-40, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24583966

RESUMEN

OBJECTIVES: Chlamydia trachomatis (CT) reporting rates from sexually transmitted infection clinics and general practitioners have shown a rising trend in the Netherlands. It is unknown to what extent this reflects increased CT transmission or improved case finding. To achieve more insight into the CT epidemic, we explored the CT IgG seroprevalence (a marker of past CT infection) in the general population of the Netherlands in 1996 and in 2007. METHODS: From two population-based studies in 1996 and 2007, serum samples, demographic and sexual behaviour outcomes were examined, including 1246 men and 1930 women aged 15-39 years. Serum CT IgG antibodies were analysed using the Medac CT IgG ELISA test. Multivariate logistic regression analyses explored the seroprevalence and determinants over time. RESULTS: The CT IgG seroprevalence was higher in women than in men (10% vs 6%). Among women aged 25-39 years the seroprevalence was lower in 2007 (9%) than in 1996 (14%; adjusted OR (aOR) 0.6, 95% CI 0.4 to 0.8). There was no statistical evidence of a difference in seroprevalence within birth cohorts. Factors associated with seropositivity were male gender (aOR 0.4, 95% CI 0.3 to 0.7), a self-reported history of CT infection (aOR 5.1, 95% CI 2.6 to 10.0), age 25-39 years (aOR 1.7, 95% CI 1.1 to 2.7), non-Western ethnicity (aOR 2.2, 95% CI 1.4 to 3.3) and ≥ 2 recent sexual partners (aOR 2.2, 95% CI 1.3 to 3.5). CONCLUSIONS: Between 1996 and 2007 the proportion of individuals in the general population with CT IgG antibodies was lower among women aged 25-39 years, but remained similar among younger women and men.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Infecciones por Chlamydia/epidemiología , Chlamydia trachomatis/aislamiento & purificación , Inmunoglobulina G/sangre , Conducta Sexual/estadística & datos numéricos , Adolescente , Adulto , Distribución por Edad , Infecciones por Chlamydia/inmunología , Chlamydia trachomatis/inmunología , Estudios Transversales , Femenino , Humanos , Masculino , Países Bajos/epidemiología , Vigilancia de la Población , Factores de Riesgo , Estudios Seroepidemiológicos , Distribución por Sexo , Parejas Sexuales
5.
Allergy ; 68(1): 74-83, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23137012

RESUMEN

BACKGROUND: Lipids are required for mice sensitization to Ber e 1, Brazil nut major allergen. Here, we characterized different lipid fractions extracted from Brazil nuts and the lipid-binding ability of Ber e 1. Further, we determined their in vivo ability to induce Ber-specific anaphylactic antibodies and the role of invariant natural killer T (iNKT) cells in this process. METHODS: Wild-type (WT) and iNKT cell-deficient mice were sensitized with Ber e 1 and specific lipid fractions, and anaphylactic antibodies were measured by enzyme-linked immunosorbent assay (ELISA) and passive cutaneous anaphylaxis (PCA). The lipid-binding characteristic of Ber e 1 (Ber) was established by using fluorescent probes and (15) N-labeled NMR. In vitro production of IL-4 was determined in Ber/lipid C-stimulated mouse iNKT cells and human T-cell lines containing NKTs primed with CD1d+C1R transfectants by flow cytometry and ELISA, respectively. RESULTS: Only one specific lipid fraction (lipid C), containing neutral and common phospholipids, induced Ber anaphylactic antibodies in mice. Ber e 1 has a lipid-binding site, and our results indicated an interaction between Ber e 1 and lipid C. iNKT-deficient mice produced lower levels of anaphylactic antibodies than WT mice. In vitro, Ber/lipid C-stimulated murine iNKT cells produced IL-4 but not IFN-gamma. Human T-cell lines derived from nut-allergic patients produced IL-4 to Ber/lipid C in a CD1d- and dose-dependent manner. CONCLUSION: Lipid fraction C from Brazil nut presents an essential adjuvant activity to Ber e 1 sensitization, and iNKT cells play a critical role in the development of Brazil nut-allergic response.


Asunto(s)
Lípidos/inmunología , Células T Asesinas Naturales/inmunología , Hipersensibilidad a la Nuez/inmunología , Albuminas 2S de Plantas/química , Albuminas 2S de Plantas/inmunología , Adolescente , Adulto , Alérgenos/inmunología , Animales , Anticuerpos/sangre , Anticuerpos/inmunología , Antígenos de Plantas/química , Antígenos de Plantas/inmunología , Sitios de Unión , Femenino , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Activación de Linfocitos/inmunología , Masculino , Ratones , Hipersensibilidad a la Nuez/metabolismo , Unión Proteica , Células Th2/inmunología , Adulto Joven
6.
Pharmacogenomics J ; 12(3): 267-76, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21173785

RESUMEN

The impact of biogeographical ancestry, self-reported 'race/color' and geographical origin on the frequency distribution of 10 CYP2C functional polymorphisms (CYP2C8*2, *3, *4, CYP2C9*2, *3, *5, *11, CYP2C19*2, *3 and *17) and their haplotypes was assessed in a representative cohort of the Brazilian population (n=1034). TaqMan assays were used for allele discrimination at each CYP2C locus investigated. Individual proportions of European, African and Amerindian biogeographical ancestry were estimated using a panel of insertion-deletion polymorphisms. Multinomial log-linear models were applied to infer the statistical association between the CYP2C alleles and haplotypes (response variables), and biogeographical ancestry, self-reported Color and geographical origin (explanatory variables). The results showed that CYP2C19*3, CYP2C9*5 and CYP2C9*11 were rare alleles (<1%), the frequency of other variants ranged from 3.4% (CYP2C8*4) to 17.3% (CYP2C19*17). Two distinct haplotype blocks were identified: block 1 consists of three single nucleotide polymorphisms (SNPs) (CYP2C19*17, CYP2C19*2 and CYP2C9*2) and block 2 of six SNPs (CYP2C9*11, CYP2C9*3, CYP2C9*5, CYP2C8*2, CYP2C8*4 and CYP2C8*3). Diplotype analysis generated 41 haplotypes, of which eight had frequencies greater than 1% and together accounted for 96.4% of the overall genetic diversity. The distribution of CYP2C8 and CYP2C9 (but not CYP2C19) alleles, and of CYP2C haplotypes was significantly associated with self-reported Color and with the individual proportions of European and African genetic ancestry, irrespective of Color self-identification. The individual odds of having alleles CYP2C8*2, CYP2C8*3, CYP2C9*2 and CYP2C9*3, and haplotypes including these alleles, varied continuously as the proportion of European ancestry increased. Collectively, these data strongly suggest that the intrinsic heterogeneity of the Brazilian population must be acknowledged in the design and interpretation of pharmacogenomic studies of the CYP2C cluster in order to avoid spurious conclusions based on improper matching of study cohorts. This conclusion extends to other polymorphic pharmacogenes among Brazilians, and most likely to other admixed populations of the Americas.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/genética , Población Negra/genética , Sistema Enzimático del Citocromo P-450/genética , Indígenas Sudamericanos/genética , Polimorfismo de Nucleótido Simple , Población Blanca/genética , Brasil/epidemiología , Análisis por Conglomerados , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP2C8 , Citocromo P-450 CYP2C9 , Frecuencia de los Genes , Haplotipos , Humanos , Oportunidad Relativa
7.
J Chromatogr A ; 1663: 462740, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-34942489

RESUMEN

Human purine nucleoside phosphorylase (HsPNP) catalyzes reversible phosphorolysis of nucleosides and deoxynucleosides in the purine cascade. HsPNP has been a target on behalf of the development of new leads for the treatment of a variety of T-cell mediated disorders. Several studies on the HsPNP are focused on the identification of effective, safe, and selective inhibitors. Therefore, this study describes the development of direct, simple, reliable, and inexpensive enzymatic assays to screen HsPNP inhibitors. Initially, HsPNP was covalently immobilized on the surface of magnetic particles (MPs). Due to the versatility of the MPs as solid support for enzyme immobilization, two different methods to monitor the enzyme activity are presented. Firstly, the activity of HsPNP-MPs was assessed offline by HPLC-DAD quantifying the formed hypoxanthine. Then, HsPNP-MPs were trapped in a peek tube, furnishing a microreactor which was inserted on-flow in an HPLC-DAD system to monitor the enzyme activity by the hypoxanthine quantification. Kinetic assays provided KMapp values for the inosine substrate of 488.2 ± 49.1 and 1084 ± 111 µM for the offline and on-flow assays, respectively. For the first time, kinetic studies for Pi as substrate using the HsPNP-MPs exhibits a Michaelis-Menten kinetic, yielding KMapp values for offline and on-flow of 521.2 ± 62.9 µM and 601 ± 66.5 µM, respectively. Inhibition studies conducted with a fourth generation immucillin derivative (DI4G) were employed as proof of concept to validate the use of the HsPNP-MPs assays for screening purposes. Additionally, a small library containing 11 compounds was used to assess the selectivity of the developed assays. The results showed that both presented assays can be applied to selectively recognizing and characterizing HsPNP inhibitors. Particularly, the on-flow method exhibited a high throughput and performance because of its automation and represents an easy and practical approach to reuse the HsPNP-MPs. Besides, this novel enzyme activity assay model can be further applied to other biological targets.


Asunto(s)
Fenómenos Magnéticos , Purina-Nucleósido Fosforilasa , Inhibidores Enzimáticos/farmacología , Humanos , Cinética , Nucleósidos de Purina , Purina-Nucleósido Fosforilasa/metabolismo
8.
Nat Med ; 7(9): 1057-62, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11533711

RESUMEN

Type 1 diabetes (T1D) in non-obese diabetic (NOD) mice may be favored by immune dysregulation leading to the hyporesponsiveness of regulatory T cells and activation of effector T-helper type 1 (Th1) cells. The immunoregulatory activity of natural killer T (NKT) cells is well documented, and both interleukin (IL)-4 and IL-10 secreted by NKT cells have important roles in mediating this activity. NKT cells are less frequent and display deficient IL-4 responses in both NOD mice and individuals at risk for T1D (ref. 8), and this deficiency may lead to T1D (refs. 1,6-9). Thus, given that NKT cells respond to the alpha-galactosylceramide (alpha-GalCer) glycolipid in a CD1d-restricted manner by secretion of Th2 cytokines, we reasoned that activation of NKT cells by alpha-GalCer might prevent the onset and/or recurrence of T1D. Here we show that alpha-GalCer treatment, even when initiated after the onset of insulitis, protects female NOD mice from T1D and prolongs the survival of pancreatic islets transplanted into newly diabetic NOD mice. In addition, when administered after the onset of insulitis, alpha-GalCer and IL-7 displayed synergistic effects, possibly via the ability of IL-7 to render NKT cells fully responsive to alpha-GalCer. Protection from T1D by alpha-GalCer was associated with the suppression of both T- and B-cell autoimmunity to islet beta cells and with a polarized Th2-like response in spleen and pancreas of these mice. These findings raise the possibility that alpha-GalCer treatment might be used therapeutically to prevent the onset and recurrence of human T1D.


Asunto(s)
Diabetes Mellitus Tipo 1/prevención & control , Galactosilceramidas/farmacología , Células Asesinas Naturales/inmunología , Animales , Anticuerpos Monoclonales/farmacología , Antígenos CD1/genética , Ciclofosfamida/toxicidad , Diabetes Mellitus Tipo 1/inducido químicamente , Diabetes Mellitus Tipo 1/inmunología , Interferón gamma/metabolismo , Interleucina-4/metabolismo , Interleucina-7/farmacología , Células Asesinas Naturales/efectos de los fármacos , Selectina L/metabolismo , Activación de Linfocitos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Ratones Mutantes , Receptores de Interleucina/efectos de los fármacos , Receptores de Interleucina/inmunología , Receptores de Interleucina-10 , Bazo/efectos de los fármacos , Bazo/metabolismo
9.
J Exp Med ; 180(2): 653-61, 1994 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-8046338

RESUMEN

We analyzed the phenotype and V beta-T cell receptor (TCR) repertoire, together with interleukin 7 receptor (IL-7R) expression in unfractionated thymocytes stimulated in vitro with IL-7. This culture system results in a specific proliferation of mature thymocytes belonging to the CD3+CD4-, CD4+8-, and CD4-8+ subsets. IL-7 induced a preferential expansion of V beta 8.2+CD4-8- and V beta 8.2+CD4-8- thymocytes. This phenomenon is not observed in beta 2-microglobulin-deficient mice, showing that a fraction of CD4+8- thymocytes, enriched in V beta 8.2+ cells, is selected by class I molecules in normal mice, as are a large proportion of CD4-8- alpha beta TCR+ thymocytes. Our findings also establish that IL-7 plays a major role in the expansion of rare thymocyte subsets, which could exert important functions in inflammatory and immune responses.


Asunto(s)
Antígenos CD4/inmunología , Antígenos CD8/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Interleucina-7/fisiología , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T/inmunología , Animales , Células Cultivadas , Antígenos de Histocompatibilidad Clase II/inmunología , Activación de Linfocitos , Masculino , Ratones , Ratones Endogámicos C3H , Fenotipo , Receptores de Interleucina/metabolismo , Receptores de Interleucina-7 , Timo/citología , Timo/inmunología , Microglobulina beta-2/inmunología
10.
J Microsc ; 239(1): 46-53, 2010 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20579268

RESUMEN

Bitumen is a complex mixture of hydrocarbons for which microstructural understanding is incomplete. In an effort to detail this microstructure, a asphalt cement sample (CAP 30/45) was analysed by thermal phase detection atomic force microscopy. Phase contrast and topography images showed that sample morphology is highly dependent on temperature. The 'bee structure' changed considerably at temperatures between 50 degrees C and 56 degrees C. A decrease of the oscillation amplitude was observed upon heating and the 'bees' completely disappeared at temperatures above 57 degrees C. When the temperature was decreased after melting at 170 degrees C, the 'bees' began to nucleate gradually at temperatures of 57 degrees C and its evolution with time was followed. Changes in morphology were compared to thermal analysis results and a model for the 'bee' structure was proposed.

11.
J Nanosci Nanotechnol ; 10(9): 6234-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21133180

RESUMEN

Electrical characteristics of multi-walled carbon nanotubes (MWNTs) grown by chemical vapor deposition have been investigated as a function of the bias voltage, nanotubes length and temperature, in 2 and 4 terminal configurations. Nanotubes were deposited over metal electrodes using ac dielectrophoresis method. For better contacts between the nanotubes and electrodes, Ni and Pd films were deposited by an electroless deposition technique. Differential conductance was found to rise considerably with bias, and this effect was more pronounced for Ni. Using 2 and 4 terminal configurations, electrical resistance measurements for individual MWNTs were performed, and the results were interpreted using the model of nanotube as a resistive transmission line, where current at low bias flows mainly through the two outermost shells.

12.
Cell Biol Toxicol ; 25(3): 245-51, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18465199

RESUMEN

The leukemia cell line HL60 is widely used in studies of the cell cycle, apoptosis, and adhesion mechanisms in cancer cells. We conducted a focused cytogenetic study in an HL60 cell line, by analyzing GTG-banded chromosomes before and after treatment with pisosterol (at 0.5, 1.0, and 1.8 microg/ml), a triterpene isolated from Pisolithus tinctorius, a fungus collected in the Northeast of Brazil. Before treatment, 99% of the cells showed the homogeneously staining region (HSR) 8q24 aberration. After treatment with 1.8 microg/ml pisosterol, 90% of the analyzed cells lacked this aberration. We further performed a pulse test, in which the cells treated with pisosterol (0.5, 1.0, and 1.8 microg/ml) were washed and re-incubated in the absence of pisosterol. Only 30% of the analyzed cells lacked the HSR 8q24 aberration, suggesting that pisosterol probably blocks the cells with HSRs at interphase. No effects were detected at lower concentrations. At the highest concentration examined (1.8 microg/ml), pisosterol also inhibited cell growth, but this effect was not observed in the pulse test, reinforcing our hypothesis that, at the concentrations tested, pisosterol probably does not induce cell death in the HL60 line. The results found for pisosterol were compared with those for doxorubicin. Cells that do not show a high degree of gene amplification (HSRs and double-minute chromosomes) have a less aggressive and invasive behavior and are easy targets for chemotherapy. Therefore, further studies are needed to examine the use of pisosterol in combination with conventional anti-cancer therapy.


Asunto(s)
Antineoplásicos/toxicidad , Basidiomycota/química , Ciclo Celular/efectos de los fármacos , Amplificación de Genes/efectos de los fármacos , Células HL-60/efectos de los fármacos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Terpenos/toxicidad , Aberraciones Cromosómicas/efectos de los fármacos , Bandeo Cromosómico , Doxorrubicina/toxicidad , Ensayos de Selección de Medicamentos Antitumorales , Células HL-60/fisiología , Humanos , Índice Mitótico , Extractos Vegetales/toxicidad
13.
Br J Oral Maxillofac Surg ; 57(2): 140-144, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30612839

RESUMEN

Our aim was to give a morphometric description of the interproximal bone between the anterior maxillary teeth of subjects with class III facial deformity, who were candidates for segmented Le Fort I osteotomy. We measured the width of the interproximal bone from the upper right canine to the upper left canine in cone-beam computed tomographic images of 35 subjects, and identified five interproximal areas of measurement. The lower and upper measurements were established 5mm and 10mm from the cervical crest of the interproximal bone. A paired samples t test and Pearson's correlation coefficient were applied and probabilities of less than 0.05 were accepted as significant. In all the scans of interproximal bone, the apical zone was significantly wider than the inferior zone (p<0.001). The area between the central incisors was the widest, with a mean (SD) of 2.42 (0.68) mm in the lower, and 4.27 (0.99) mm in the upper, region followed by the space between the canines and lateral incisors. The minimum interproximal spaces in the lowest area were between 1.1 and 1.5mm, which suggested the potential for damage to the teeth during segmental osteotomy. The interproximal spaces were at potential risk of dental and periodontal injuries, and the area between the central incisors seemed to be most suited to interproximal osteotomies in "surgery first".


Asunto(s)
Osteotomía Maxilar , Osteotomía Le Fort , Proceso Alveolar , Tomografía Computarizada de Haz Cónico , Humanos , Maxilar
14.
Hum Exp Toxicol ; 27(10): 751-6, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19042960

RESUMEN

A liquid alcoholic extract of Papaver somniferum named Elixir Paregorico is extensively used for diarrheal diseases in Brazil. Its increased popularity has brought concerns and fears over the safety of this herbal product. Given the lack of investigative clinical studies, in this regard, this study investigated whether Elixir Paregorico administration causes any noticeable toxic effects in healthy volunteers. In all, 28 middle-aged healthy male (n = 14) and female (n = 14) were enrolled. After screening and a washout period, eligible subjects received four oral doses per day of Elixir Paregorico (3 mL diluted in 30 mL of water) over a 10-day period. Altogether, all 28 participants completed the study. The results of hematological and biochemical tests performed pre and post-treatment were within the normal range. In both male and female volunteers, there were no statistical differences (P > 0.05) in the results of clinical and laboratory tests performed at screening, on 5th and 10th day visits, and at final assessment. Although mild adverse events were related, which subsided spontaneously, no serious untoward reactions were reported following Elixir Paregorico administration. To our knowledge, this is the first demonstration that Elixir Paregorico administered four times a day for 10 days is safe and does not cause any noticeable toxic effect in healthy volunteers.


Asunto(s)
Antidiarreicos/efectos adversos , Opio/efectos adversos , Administración Oral , Adolescente , Adulto , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Pruebas de Química Clínica , Femenino , Pruebas Hematológicas , Humanos , Masculino , Pruebas de Toxicidad , Adulto Joven
15.
Int J Oral Maxillofac Surg ; 46(7): 861-866, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28366448

RESUMEN

This study aimed to describe the condylar layer and cartilage island in subjects with unilateral condylar hyperplasia (UCH). Five individuals (15-18 years old) with a diagnosis of UCH, treated in a university hospital in Temuco, Chile, were included. The analysis examined the presence, extension, and thickness of the layers on the condylar surface, the number, depth, and area of the cartilage islands, and the argyrophilic proteins of the nucleolar organizer region (AgNOR) score. Statistical significance was set at P<0.05. The fibrocartilaginous layer was thickest (0.13±0.05mm) and the joint layer was thinnest (0.07±0.01mm) (P<0.05). With respect to the number, depth, and area of the islands, case 1 presented the highest values, followed by case 2; the cartilage island was related to the fibrocartilaginous layer (P<0.05). All cases had AgNOR proteins in the proliferative and fibrocartilaginous layers, as well as the islands with the greatest presence of chondrocytes (P=0.245). A relationship was observed between the histopathological alterations in the different layers on the condylar surface and the thickness of the fibrocartilaginous layer, as well as the thickness of the latter and the number, depth, and area of the cartilage islands in the trabecular bone.


Asunto(s)
Cartílago Articular/patología , Maloclusión de Angle Clase III/patología , Cóndilo Mandibular/patología , Trastornos de la Articulación Temporomandibular/patología , Adolescente , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/cirugía , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Hiperplasia/diagnóstico por imagen , Hiperplasia/patología , Hiperplasia/cirugía , Masculino , Maloclusión de Angle Clase III/diagnóstico por imagen , Maloclusión de Angle Clase III/cirugía , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/cirugía , Trastornos de la Articulación Temporomandibular/diagnóstico por imagen , Trastornos de la Articulación Temporomandibular/cirugía , Tomografía Computarizada de Emisión de Fotón Único , Resultado del Tratamiento
16.
Int J Oral Maxillofac Surg ; 35(2): 155-8, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15955666

RESUMEN

This retrospective study analyzed the etiologic factors, location and treatments for patients with oroantral or oronasal communications (OAC or ONC). Data analysis extended to gender, age, etiology, location, type of treatment and short-term complications from January 1988 to May 2004. A total of 112 patients with 101 (90%) OAC and 11 (10%) ONC were included. The main etiology for OAC was tooth extraction (95%) with similar prevalence between right (49%) and left (51%) side. For ONC, pathological conditions (27%) and exodontia (27%) were the most prevalent. For the treatment of OAC, suture was the technique most frequently used (60%), followed by buccal fat pad (28%), buccal flap (9%), palatal flap (2%) and one dental transplant (1%). For ONC, the following treatments were used: suture (46%), buccal flap (36%) and palatal flap (18%). Failure to eliminate the communication occurred in six (6%) patients of the OAC group and three (27%) of the ONC group. The results confirm that tooth extraction was the most common etiologic factor for ONC and OAC. Suture, when the communication was small (3-5 mm), and the use of a buccal fat pad (100% successful), when a larger communication existed (>5 mm), seemed to be the two best choices for treatment.


Asunto(s)
Fístula Oral/cirugía , Extracción Dental/efectos adversos , Tejido Adiposo/trasplante , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mucosa Bucal/trasplante , Fístula Oral/etiología , Fístula Oroantral/etiología , Fístula Oroantral/cirugía , Estudios Retrospectivos , Colgajos Quirúrgicos
17.
Artículo en Inglés | MEDLINE | ID: mdl-26809594

RESUMEN

OBJECTIVE: Zygomatic implants may be used for dental rehabilitation in atrophic maxillae. The aim of this study was to establish experimentally the areas of stress distribution using 2 kinds of "All-On-Four" maxillary procedures. STUDY DESIGN: The best position to insert the implants was selected using polyurethane craniomaxillary models and surgical guides were made. Group 1 was designed with two posterior zygomatic implants and two conventional anterior implants, and group 2 with two posterior zygomatic implants and two anterior zygomatic implants. A titanium bar was built to link the 4 implants in both groups. Photoelastic replicas of these models were made and the implants were inserted using the surgical guides. An Instrom 4411 testing machine was used to perform a unilateral compressive loading at the level of the right first molar until 2mm of displacement was obtained. RESULTS: Group 1 showed a high strain concentration in the right lateral orbital region at the level of the apex of the zygomatic implant. Less strain was noticed at the apical levels of the conventional implants in the anterior sector and of the contralateral zygomatic implant. Group 2 showed high strains in the lateral inferior orbital area. The load was low in the alveolar bone sector. DISCUSSION: Zygomatic bone and paranasal structures are loaded at high levels when zygomatic implants are used to stabilize a full maxillary prosthodontic rehabilitation on 4 implants. The use of 4 zygomatic implants loads the alveolar bone to a lower extent and seems better suited from a mechanical point of view than the use of 2 zygomatic implants.


Asunto(s)
Implantación Dental Endoósea/instrumentación , Implantación Dental Endoósea/métodos , Prótesis Dental de Soporte Implantado , Maxilar/cirugía , Estrés Mecánico , Cigoma/cirugía , Fenómenos Biomecánicos , Diseño de Prótesis Dental , Prótesis Dental de Soporte Implantado/efectos adversos , Humanos , Arcada Edéntula/cirugía , Ensayo de Materiales/métodos
18.
Int J Oral Maxillofac Surg ; 44(8): 1005-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25735535

RESUMEN

The aim of this study was to evaluate the microscopic structure and chemical composition of titanium bone plates and screws retrieved from patients with a clinical indication and to relate the results to the clinical conditions associated with the removal of these devices. Osteosynthesis plates and screws retrieved from 30 patients between January 2010 and September 2013 were studied by metallographic, gas, and energy dispersive X-ray (EDX) analyses and the medical records of these patients were reviewed. Forty-eight plates and 238 screws were retrieved. The time elapsed between plate and screw insertion and removal ranged between 11 days and 10 years. Metallographic analysis revealed that all the plates were manufactured from commercially pure titanium (CP-Ti). The screw samples analyzed consisted of Ti-6Al-4V alloy, except four samples, which consisted of CP-Ti. Titanium plates studied by EDX analysis presented greater than 99.7% titanium by mass. On gas analysis of Ti-6Al-4V screws, three samples were outside the standard values. One CP-Ti screw sample and one plate sample also presented an oxygen analysis value above the standard. The results indicated that the physical properties and chemical compositions of the plates and screws did not correspond with the need to remove these devices or the time of retention.


Asunto(s)
Placas Óseas , Tornillos Óseos , Procedimientos Quirúrgicos Ortognáticos/instrumentación , Titanio/química , Aleaciones , Remoción de Dispositivos , Humanos , Microscopía , Espectrometría por Rayos X , Factores de Tiempo
19.
Int J Oral Maxillofac Surg ; 44(10): 1281-6, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26112995

RESUMEN

The aim of this research was to compare the condylar morphology of patients with unilateral condylar hyperplasia (UCH) and patients with a class III skeletal relationship using cone beam computed tomography (CBCT). A prospective study was conducted on patients with facial asymmetry attending the division of oral and maxillofacial surgery of the study university in Chile. Fifteen patients with UCH and 15 with a class III skeletal relationship were selected. Linear measurements of the condylar processes were obtained at a scale of 1:1 using the software Ez3D Viewer Plus. Analysis of variance (ANOVA) and the paired t-test were used, considering P<0.05. Patients with UCH presented statistical differences between the hyperplastic condyle and non-hyperplastic condyle for anteroposterior and mediolateral diameters, condylar neck length, and ramus height. Patients with a class III skeletal relationship showed no differences between the right and left sides; the morphology of their condyles was similar to the condyles with hyperplasia and presented statistical differences when compared with the non-hyperplastic condyles (one-way ANOVA, P<0.05). The condylar morphology of UCH patients could be related to the development of a class III skeletal relationship. These findings provide an insight into the possibility of some class III patients presenting bilateral condylar hyperplasia.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Asimetría Facial/diagnóstico por imagen , Maloclusión de Angle Clase III/diagnóstico por imagen , Cóndilo Mandibular/diagnóstico por imagen , Adolescente , Adulto , Asimetría Facial/patología , Femenino , Humanos , Hiperplasia/diagnóstico por imagen , Hiperplasia/patología , Masculino , Maloclusión de Angle Clase III/patología , Cóndilo Mandibular/patología , Estudios Prospectivos , Interpretación de Imagen Radiográfica Asistida por Computador
20.
Int J Oral Maxillofac Surg ; 44(11): 1346-50, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26187045

RESUMEN

The Nasal Obstruction Symptom Evaluation (NOSE) scale is a reliable and valid instrument used widely in otorhinolaryngology to evaluate nasal obstruction symptoms in patients with nasal disorders. The purpose of this study was to assess nasal obstruction symptoms prospectively in patients undergoing surgically assisted rapid maxillary expansion (SARME) using the NOSE scale. Sixteen patients were studied (mean age 31±7.7 years), 10 women and six men, all with a transverse maxillary deficiency and an indication for SARME. Hyrax type devices were placed preoperatively and SARME was performed using Kraut's technique. The NOSE scale was applied prospectively to assess nasal obstruction symptoms. The results were recorded for each score on a scale ranging from 0 to 4, and these scores were multiplied by 5, generating a balanced scale from 0 to 100. Data were stratified according to NOSE scores, and nasal obstruction was categorized as mild (0-25), moderate (26-50), or severe (>50). The questionnaire was administered twice, first preoperatively and then at 6 months after surgery, and the results compared. Data were analyzed statistically using SAS statistical package software and showed that patients experienced a subjective improvement or did not have a worsening of nasal obstruction symptoms after SARME.


Asunto(s)
Obstrucción Nasal/diagnóstico , Obstrucción Nasal/prevención & control , Técnica de Expansión Palatina , Adulto , Femenino , Humanos , Masculino , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Resultado del Tratamiento
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