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2.
Mater Sci Eng C Mater Biol Appl ; 124: 112008, 2021 May.
Article in English | MEDLINE | ID: mdl-33947579

ABSTRACT

The formation of a porous oxide surface doped with osteoconductive elements, Ca, P and Mg, to enhance osseointegration, was achieved through micro arc oxidation. Micro arc oxidation parameters, such as electrolyte composition, concentration and applied voltage, were studied to understand their effect on the morphology and chemical composition of the samples surface. Considering the optimum atomic concentration reported in literature for each osteoconductive element, microporous Ta anodic oxide samples treated with calcium acetate (CaA) and ß-glycerophosphate (ß-GP) revealed that an increase of ß-GP molarity in the electrolyte boosts Ca incorporation, as well as, increasing the porosity. In adding magnesium acetate (MgA) to the electrolyte, when composed by CaA + ß-GP, both addition and variation of MgA did not affect the surface morphology along the samples, being incorporated into the oxide layer for 0.1 M. Finally, in vitro tests were carried out to study the biocompatibility of Ta, to verify the cytotoxicity of the samples and their behavior towards cells, by performing adhesion and differentiation tests with the MC3T3-E1 cell line. Cytotoxicity tests revealed that the samples were non-toxic. Despite none of the samples having been raised up through cell adhesion tests, cell differentiation revealed promising results for the Ta-CaP.


Subject(s)
Tantalum , Titanium , Acetates , Magnesium Compounds , Osteoblasts , Oxides/pharmacology , Surface Properties , Tantalum/pharmacology
5.
Leukemia ; 30(4): 929-36, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26639181

ABSTRACT

In chronic lymphocytic leukemia (CLL) the level of minimal residual disease (MRD) after therapy is an independent predictor of outcome. Given the increasing number of new agents being explored for CLL therapy, using MRD as a surrogate could greatly reduce the time necessary to assess their efficacy. In this European Research Initiative on CLL (ERIC) project we have identified and validated a flow-cytometric approach to reliably quantitate CLL cells to the level of 0.0010% (10(-5)). The assay comprises a core panel of six markers (i.e. CD19, CD20, CD5, CD43, CD79b and CD81) with a component specification independent of instrument and reagents, which can be locally re-validated using normal peripheral blood. This method is directly comparable to previous ERIC-designed assays and also provides a backbone for investigation of new markers. A parallel analysis of high-throughput sequencing using the ClonoSEQ assay showed good concordance with flow cytometry results at the 0.010% (10(-4)) level, the MRD threshold defined in the 2008 International Workshop on CLL guidelines, but it also provides good linearity to a detection limit of 1 in a million (10(-6)). The combination of both technologies would permit a highly sensitive approach to MRD detection while providing a reproducible and broadly accessible method to quantify residual disease and optimize treatment in CLL.


Subject(s)
Antigens, CD/metabolism , Flow Cytometry/standards , High-Throughput Nucleotide Sequencing/methods , Leukemia, Lymphocytic, Chronic, B-Cell/therapy , Neoplasm, Residual/diagnosis , Adolescent , Adult , Combined Modality Therapy , Europe , Female , Follow-Up Studies , Humans , Immunophenotyping , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Male , Neoplasm Staging , Neoplasm, Residual/genetics , Neoplasm, Residual/metabolism , Prognosis , Young Adult
6.
Mater Sci Eng C Mater Biol Appl ; 55: 547-55, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26117788

ABSTRACT

Nowadays, with the increase of elderly population and related health problems, knee and hip joint prosthesis are being widely used worldwide. However, failure of these invasive devices occurs in a high percentage thus demanding the revision of the chirurgical procedure. Within the reasons of failure, microbial infections, either hospital or subsequently-acquired, contribute in high number to the statistics. Staphylococcus epidermidis (S. epidermidis) has emerged as one of the major nosocomial pathogens associated with these infections. Silver has a historic performance in medicine due to its potent antimicrobial activity, with a broad-spectrum on the activity of different types of microorganisms. Consequently, the main goal of this work was to produce Ag-ZrCN coatings with antimicrobial activity, for the surface modification of hip prostheses. Thin films of ZrCN with several silver concentrations were deposited onto stainless steel 316 L, by DC reactive magnetron sputtering, using two targets, Zr and Zr with silver pellets (Zr+Ag target), in an atmosphere containing Ar, C2H2 and N2. The antimicrobial activity of the modified surfaces was tested against S. epidermidis and the influence of an activation step of silver was assessed by testing samples after immersion in a 5% (w/v) NaClO solution for 5 min. The activation procedure revealed to be essential for the antimicrobial activity, as observed by the presence of an inhibition halo on the surface with 11 at.% of Ag. The morphology analysis of the surface before and after the activation procedure revealed differences in silver distribution indicating segregation/diffusion of the metallic element to the film's surface. Thus, the results indicate that the silver activation step is responsible for an antimicrobial effect of the coatings, due to silver oxidation and silver ion release.


Subject(s)
Anti-Infective Agents/pharmacology , Coated Materials, Biocompatible , Cyanides/chemistry , Silver/chemistry , Zirconium/chemistry , Anti-Infective Agents/chemistry , Microscopy, Electron, Scanning , Photoelectron Spectroscopy
7.
Placenta ; 36(3): 262-9, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25600910

ABSTRACT

INTRODUCTION: Escherichia coli is recognized as an etiological bacteria associated with chorioamnionitis and the preterm premature rupture of fetal membranes. This pathological condition induces pro-inflammatory cytokines and degradative metalloproteinases, which are considered biological markers secreted in an acute stage of infection. Heat-shock proteins (HSPs) are an important component of the innate immunity response and are found in different pathological conditions. They have not been previously measured in human fetal membranes in response to infectious conditions. We hypothesized that the choriodecidual tissue and amniotic epithelium secreted temporal and differential Hsp-60, Hsp-70, and interleukin (IL)-1ß mediated by E. coli infection. METHODS: Fetal membranes were mounted in a two-compartment culture system and infected with two passes of live E. coli at different doses (10², 104, 105, and 106 colony-forming units (CFU)/mL) and intervals of incubation (3, 6, and 24 h). The culture medium was collected, and Hsp-60, Hsp-70, and IL-1ß were assessed using the enzyme-linked immunosorbent assay (ELISA) method. RESULTS: After 3 and 6 h of infection, E. coli induced an increase in Hsp-70 secretion in the choriodecidual tissue. However, after 24 h of incubation, Hsp-70 was downregulated and we observed an increase in IL-1ß secretion. By contrast, E. coli induced a lower Hsp-60 secretion in the amnion compared to Hsp-70. DISCUSSION: Human fetal membranes responded actively to E. coli infection, with an increase in Hsp-70 during the first hours of infection. After 24 h, there was an increase in the liberation of IL-1ß.


Subject(s)
Escherichia coli/immunology , Extraembryonic Membranes/metabolism , Extraembryonic Membranes/microbiology , HSP110 Heat-Shock Proteins/metabolism , HSP70 Heat-Shock Proteins/metabolism , Interleukin-1beta/metabolism , Up-Regulation , Amnion/immunology , Amnion/metabolism , Amnion/microbiology , Chaperonin 60/metabolism , Chorioamnionitis/immunology , Chorioamnionitis/metabolism , Chorioamnionitis/microbiology , Chorion/immunology , Chorion/metabolism , Chorion/microbiology , Decidua/immunology , Decidua/metabolism , Decidua/microbiology , Down-Regulation , Enzyme-Linked Immunosorbent Assay , Escherichia coli/isolation & purification , Escherichia coli Infections/immunology , Escherichia coli Infections/metabolism , Escherichia coli Infections/microbiology , Extraembryonic Membranes/immunology , Female , Humans , Immunity, Innate , Kinetics , Mitochondrial Proteins/metabolism , Pregnancy , Tissue Culture Techniques
8.
Leukemia ; 28(10): 1993-2004, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24618734

ABSTRACT

Chronic lymphocytic leukemia (CLL) cells located in proliferation centers are constantly stimulated by accessory cells, which provide them with survival and proliferative signals and mediate chemotherapy resistance. Herein, we designed an experimental strategy with the aim of mimicking the microenvironment found in the proliferative centers to specifically target actively proliferating CLL cells. For this, we co-cultured CLL cells and bone marrow stromal cells with concomitant CD40 and Toll-like receptor 9 stimulation. This co-culture system induced proliferation, cell-cycle entry and marked resistance to treatment with fludarabine and bendamustine. Proliferating CLL cells clustered together showed a typical morphology of activated B cells and expressed survivin protein, a member of the inhibitor of apoptosis family that is mainly expressed by CLL cells in the proliferation centers. With the aim of specifically targeting actively proliferating and chemoresistant CLL cells, we investigated the effects of treatment with YM155, a small-molecule survivin inhibitor. YM155 treatment suppressed the co-culture-induced survivin expression and that was sufficient to inhibit proliferation and effectively induce apoptosis particularly in the proliferative subset of CLL cells. Interestingly, sensitivity to YM155 was independent from common prognostic markers, including 17p13.1 deletion. Altogether, these findings provide a rationale for clinical development of YM155 in CLL.


Subject(s)
Antineoplastic Agents/chemistry , Drug Resistance, Neoplasm , Inhibitor of Apoptosis Proteins/metabolism , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Adult , Aged , Aged, 80 and over , Apoptosis , B-Lymphocytes/drug effects , B-Lymphocytes/metabolism , Bendamustine Hydrochloride , Bone Marrow Cells/cytology , CD40 Antigens/metabolism , Cell Cycle , Cell Proliferation , Coculture Techniques , Female , Gene Deletion , Humans , Imidazoles/chemistry , Leukocytes, Mononuclear/cytology , Male , Middle Aged , Naphthoquinones/chemistry , Nitrogen Mustard Compounds/chemistry , Stromal Cells/cytology , Survivin , Toll-Like Receptor 9/metabolism , Vidarabine/analogs & derivatives , Vidarabine/chemistry
9.
Enferm. glob ; 13(33): 318-327, ene. 2014.
Article in Spanish | IBECS | ID: ibc-118498

ABSTRACT

Existen diversas organizaciones y movimientos humanitarios a nivel mundial que tratan de luchar contra las expresiones de deshumanización, sin embargo, continúa la presencia de situaciones que son causas de dolor en el mundo, por lo que debemos constituir una sociedad para que el mundo sea civilizado, vivir por la calidad de vida y no por acumular cifras estadísticas. El cuidado es una característica común de todos los seres vivos. Por consiguiente, el cuidado humano se reconoce como un concepto universal, inherente a la humanidad. Heidegger, el filósofo por excelencia del cuidado, reconoce que éste es "una constitución ontológica, siempre subyacente a todo lo que el ser humano emprende, proyecta y hace". Enfermería como profesión de naturaleza social intenta que su personal, bajo una óptica humanista, ayude a la persona solicitante del cuidado a reforzar potencialidades y/o minimizar desequilibrios en su estado de salud, por ello reconoce al ser humano como un ser complejo, misterioso, estructurado por diversas dimensiones que van de lo orgánico a lo espiritual, de lo tangible a lo intangible; con inclusión del aspecto social e histórico, que lo define como un ser de interrelaciones permanentes consigo mismo y el mundo. Bajo esta perspectiva, en enfermería, se procura reconocer que la persona cuidada es una entidad única, poseedora de atributos: conciencia, intelecto, dignidad, emociones, sentimientos y saberes, por lo tanto, el cuidado en enfermería asume una dimensión humanista y comprensiva del ser, cuya subjetividad está estructurada por sus vivencias y significados, sentimientos, emociones, intuiciones, razonamientos (AU)


Nowadays, there exist several organizations of humanitarian movements all over the world which try to fight against the dehumanization expressions; however there still exists the presence of situations which are the reasons of pain in the world. That is why we must construct a better and civilized world in which people worries about the quality of life instead of accumulating statistical numbers .Care is a common feature of all human beings. Therefore, human care is recognized as a universal concept, inherent in humanity. Heidegger, the philosopher for excellence of care, recognizes that this is "an ontological constitution that is always underlying to all what the human beings begin, project and make." Nursing as a profession of social nature tries that its staff , under an humanistic perspective , helps the person interested in care to reinforce his /her abilities and /or to minimize imbalances in her /his state of health .That is why it recognizes the human beings as a complex , mysterious and structured in several dimensions being that range from the organic to the spiritual, from the tangible to the intangible , including the social and historical aspect , which defines it as a being of permanent relationships with himself and the world. Under this point of view, nursing tries to recognize that the cared person is a unique entity which has attributes such as: awareness, intellect, dignity, emotions, feelings and knowledge. Therefore, the nursing care assumes a comprehensive and humanistic dimension of the human being whose subjectivity is structured by his experiences ,meanings , feelings , emotions , intuitions ,and reasoning (AU)


Subject(s)
Humans , Male , Female , Nursing Care/organization & administration , Nursing Care/standards , Nursing Care/trends , Interpersonal Relations , Professional Practice/ethics , Professional Practice/legislation & jurisprudence , Professional Practice/standards , Nursing Care/ethics , Nursing Care/methods , Nursing Care , Social Support , Psychosocial Impact , Professional Practice/organization & administration , Professional Practice
10.
Anal Bioanal Chem ; 405(19): 6259-69, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23722890

ABSTRACT

Surface modification by means of wear protective and antibacterial coatings represents, nowadays, a crucial challenge in the biomaterials field in order to enhance the lifetime of bio-devices. It is possible to tailor the properties of the material by using an appropriate combination of high wear resistance (e.g., nitride or carbide coatings) and biocide agents (e.g., noble metals as silver) to fulfill its final application. This behavior is controlled at last by the outmost surface of the coating. Therefore, the analytical characterization of these new materials requires high-resolution analytical techniques able to provide information about surface and depth composition down to the nanometric level. Among these techniques are Rutherford backscattering spectrometry (RBS), glow discharge optical emission spectroscopy (GDOES), and angle resolved X-ray photoelectron spectroscopy (ARXPS). In this work, we present a comparative RBS-GDOES-ARXPS study of the surface characterization of Ag-TiCN coatings with Ag/Ti atomic ratios varying from 0 to 1.49, deposited at room temperature and 200 °C. RBS analysis allowed a precise quantification of the silver content along the coating with a non-uniform Ag depth distribution for the samples with higher Ag content. GDOES surface profiling revealed that the samples with higher Ag content as well as the samples deposited at 200 °C showed an ultrathin (1-10 nm) Ag-rich layer on the coating surface followed by a silver depletion zone (20-30 nm), being the thickness of both layers enhanced with Ag content and deposition temperature. ARXPS analysis confirmed these observations after applying general algorithm involving regularization in addition to singular value decomposition techniques to obtain the concentration depth profiles. Finally, ARXPS measurements were used to provide further information on the surface morphology of the samples obtaining an excellent agreement with SEM observations when a growth model of silver islands with a height d = 1.5 nm and coverage θ = 0.20 was applied to the sample with Ag/Ti = 1.49 and deposited at room temperature.


Subject(s)
Coated Materials, Biocompatible/chemistry , Metal Nanoparticles/chemistry , Photoelectron Spectroscopy , Silver/chemistry , Spectrum Analysis , Surface Properties , Titanium/chemistry
11.
Dis Esophagus ; 26(3): 246-9, 2013 Apr.
Article in English | MEDLINE | ID: mdl-22676484

ABSTRACT

Ambulatory 24-hour esophageal pH monitoring is the gold standard examination to assess esophageal acid exposure. Gender-related variation is a well-recognized physiologic phenomenon in health and disease. To date, limited gender-specific 24-hour esophageal pH monitoring data are available. The aim of this study was to obtain values of esophageal pH monitoring in males and females without reflux symptoms or gastroesophageal reflux disease (GERD) to determine if gender variation exists in esophageal acid exposure among individuals without these factors. Twenty-four-hour dual esophageal pH monitoring was performed in male and female volunteers without reflux symptoms or GERD. Values for total number of reflux episodes, episodes longer than 5 minutes, total reflux time in minutes, % time with pH below 4, and longest reflux episode in the proximal/distal esophagus were obtained and recorded for both groups. The distal channel was placed 5 cm and proximal channel 15 cm above the manometrically determined lower esophageal sphincter. Means were compared using an independent sample t-test. Sixty-seven males and 69 females were enrolled. All subjects completed esophageal 24-hour pH monitoring without difficulty. There was no age or body mass difference between groups. Females had significantly fewer reflux episodes at both esophageal measuring sites and, significantly less total reflux time and % time with pH below 4 in the distal esophagus than males. All other parameters were similar. Significant gender-related differences exist in esophageal acid exposure, especially in the distal esophagus in individuals without reflux symptoms or GERD. These differences underscore the need for gender-specific reference values for 24-hour pH monitoring, allowing for an accurate evaluation of esophageal acid exposure in symptomatic patients.


Subject(s)
Esophageal pH Monitoring , Esophagus/physiology , Gastric Acid/physiology , Adolescent , Adult , Aged , Esophageal Sphincter, Lower/physiology , Female , Gastroesophageal Reflux/physiopathology , Humans , Male , Middle Aged , Sex Factors , Time Factors , Young Adult
12.
Hum Hered ; 70(4): 255-68, 2010.
Article in English | MEDLINE | ID: mdl-21071953

ABSTRACT

BACKGROUND/AIMS: Bipolar disorder (BP) is a severe psychiatric illness, characterised by alternating episodes of depression and mania, which ranks among the top ten causes of morbidity and life-long disability world-wide. We have previously performed a whole-genome linkage scan on 6 pedigrees segregating severe BP from the well-characterised population isolate of Antioquia, Colombia. We recently collected genotypes for the same set of 382 autosomal microsatellite markers in 9 additional Antioquian BP pedigrees. Here, we report the analysis of the combined pedigree set. METHODS: Linkage analysis using both parametric and nonparametric approaches was conducted for 3 different diagnostic models: severe BP only (BPI); mood disorders (BPI, BPII and major depression); and psychosis (operationally defined by the occurrence of at least 1 episode of hallucinations and/or delusions). RESULTS AND CONCLUSION: For BPI only, the most interesting result was obtained for chromosome 7p21.1-p22.2 under a recessive model of inheritance (heterogeneity LOD score = 2.80), a region that had previously been linked to BP in a study on Portuguese Island families. For both BPI and mood disorders, nonparametric analyses identified a locus on chromosome 12ct-q14 (nonparametric linkage = 2.55 and 2.35, respectively). This locus has not previously been reported as a candidate region for BP. Additional candidate regions were found on chromosomes 1p22-31 (mood disorders) and 21q21-22 (BPI), 2 loci that have repeatedly been implicated in BP susceptibility. Linkage analysis of psychosis as a phenotype identified candidate regions on chromosomes 2q24-31 and 16p12-q12. The finding on chromosome 16p is noteworthy because the same locus has been implicated by genome-wide association analyses of BP.


Subject(s)
Bipolar Disorder/genetics , Chromosomes, Human, Pair 16 , Chromosomes, Human, Pair 1 , Chromosomes, Human, Pair 21 , Chromosomes, Human, Pair 7 , Adolescent , Adult , Chromosome Mapping , Colombia , Female , Genetic Linkage , Humans , Male , Pedigree , Young Adult
13.
Diabetes Technol Ther ; 12(8): 635-9, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20615105

ABSTRACT

BACKGROUND: Comparison of hypoglycemia incidence among tight glycemic control (TGC) protocols is a crucial aspect that has not been done in previous trials. This study compared the incidence of hypoglycemia using three TGC protocols in critically ill patients. METHODOLOGY: This was a prospective study of 420 patients over 18 months. Patients were divided into three groups by TGC protocol: A (modified Leuven protocol), B (Georgia Hospital Association protocol, target blood glucose [BG] 80-110 mg/dL), and C (modified Georgia Hospital Association protocol, target BG 90-140 mg/dL). End points included differences in the incidence of first-degree hypoglycemia (BG or= 180 mg/dL). RESULTS: A total of 34,497 BG samples were analyzed: group A, 11,202 (32.47%); group B, 9,627 (27.91%); and group C, 13,668 (39.62%). First-degree hypoglycemia was more frequent in group A (348 episodes [3.11%]) compared to group B (209 episodes [2.17%] [odds ratio (OR) 1.45, 95% confidence interval (CI) 1.25-1.172, P = 0.001]) and group C (266 episodes [1.95%] [OR 1.66, 95% CI 1.37-1.89, P = 0.001]). Second-degree hypoglycemia was more frequent in group A (131 episodes [1.17%]) compared to group B (62 episodes [0.64%] [OR 1.83, 95% CI 1.22-1.72, P = 0.001]) and group C (58 episodes [0.42%] [OR 2.77, 95% CI 2.04-3.79, P = 0.001]). No significant difference was found when groups B and C were compared (P = 0.10 and P = 0.06, respectively). Hyperglycemia was significantly more common in group A (2,175 episodes [19.42%]) compared to group B (1,333 episodes [13.83%] [OR 1.49, 95% CI 1.39-1.62, P = 0.001], but there was no significant difference compared to group C (2,560 episodes [18.73%] [P = 0.17]). CONCLUSIONS: TGC protocols vary in their risk of inducing hypoglycemia. Whether this translates into differences in clinical outcomes such as mortality and adverse effects is still to be determined by future studies.


Subject(s)
Blood Glucose , Hypoglycemia/epidemiology , Aged , Female , Humans , Hyperglycemia/blood , Hyperglycemia/epidemiology , Hypoglycemia/blood , Incidence , Intensive Care Units , Male , Middle Aged , Odds Ratio , Prospective Studies , Risk
14.
Am J Med Genet B Neuropsychiatr Genet ; 150B(7): 998-1006, 2009 Oct 05.
Article in English | MEDLINE | ID: mdl-19319892

ABSTRACT

We previously reported linkage of bipolar disorder to 5q33-q34 in families from two closely related population isolates, the Central Valley of Costa Rica (CVCR) and Antioquia, Colombia (CO). Here we present follow up results from fine-scale mapping in large CVCR and CO families segregating severe bipolar disorder, BP-I, and in 343 population trios/duos from CVCR and CO. Employing densely spaced SNPs to fine map the prior linkage peak region increases linkage evidence and clarifies the position of the putative BP-I locus. We performed two-point linkage analysis with 1134 SNPs in an approximately 9 Mb region between markers D5S410 and D5S422. Combining pedigrees from CVCR and CO yields a LOD score of 4.9 at SNP rs10035961. Two other SNPs (rs7721142 and rs1422795) within the same 94 kb region also displayed LOD scores greater than 4. This linkage peak coincides with our prior microsatellite results and suggests a narrowed BP-I susceptibility regions in these families. To investigate if the locus implicated in the familial form of BP-I also contributes to disease risk in the population, we followed up the family results with association analysis in duo and trio samples, obtaining signals within 2 Mb of the peak linkage signal in the pedigrees; rs12523547 and rs267015 (P = 0.00004 and 0.00016, respectively) in the CO sample and rs244960 in the CVCR sample and the combined sample, with P = 0.00032 and 0.00016, respectively. It remains unclear whether these association results reflect the same locus contributing to BP susceptibility within the extended pedigrees.


Subject(s)
American Indian or Alaska Native/genetics , Bipolar Disorder/genetics , Chromosomes, Human, Pair 5/genetics , Genetic Linkage , Pedigree , Colombia , Costa Rica , Family , Female , Gene Frequency , Genetic Markers , Genetic Predisposition to Disease , Humans , Latin America , Lod Score , Male , Polymorphism, Single Nucleotide/genetics
15.
Langmuir ; 24(16): 8667-71, 2008 Aug 19.
Article in English | MEDLINE | ID: mdl-18642858

ABSTRACT

A comparative study of the chemical functionalization of undoped, n- and p-type GaN layers grown on sapphire substrates by metal-organic chemical vapor deposition was carried out. Both types of samples were chemically functionalized with 3-aminopropyltriethoxysilane (APTES) using a well-established silane-based approach for functionalizing hydroxylated surfaces. The untreated surfaces as well as those modified by hydroxylation and APTES deposition were analyzed using angle-resolved X-ray photoelectron spectroscopy. Strong differences were found between the APTES growth modes on n- and p-GaN surfaces that can be associated with the number of available hydroxyl groups on the GaN surface of each sample. Depending on the density of surface hydroxyl groups, different mechanisms of APTES attachment to the GaN surface take place in such a way that the APTES growth mode changes from a monolayer to a multilayer growth mode when the number of surface hydroxyl groups is decreased. Specifically, a monolayer growth mode with a surface coverage of approximately 78% was found on p-GaN, whereas the formation of a dense film, approximately 3 monolayers thick, was observed on n-GaN.


Subject(s)
Electrons , Gallium/chemistry , Silanes/chemistry , X-Rays , Hydroxylation , Models, Molecular , Molecular Conformation , Propylamines , Spectrum Analysis , Surface Properties
16.
Invest. educ. enferm ; 20(2): 12-29, sept. 2002. tab, graf
Article in Spanish | LILACS, BDENF - Nursing | ID: lil-346001

ABSTRACT

Estudio descriptivo transversal para identificar las oportunidades de participación en el cuidado que el equipo de enfermería propicia a los acompañantes del paciente hospitalizado. Nace como respuesta a los interrogantes continuos desde la practica académica y por vivencias personales con familiares hospitalizados. Se realiza una entrevista estructurada a 265 acompañantes de instituciones de salud del segundo nivel de complejidad, en las cuales se indagó por aspectos socio-demográficos de los usuarios y acompañantes, las acciones de cuidado que ejecuta el acompañante y cuáles son indicados, explicados y apoyados por el equipo de enfermería. La educación que éste proporciona al acompañante es otro asunto que se cuestionó en la muestra. De los usuarios con acompañante el 54 por ciento son de sexo femenino, los de mayor tiempo de compañía están en el grupo etáreo de 64 a 77 años y se caracterizan por un nivel bajo de escolaridad. Como primera causa de morbilidad está los problemas gasasculares. trointestinales; seguidos de los problemas cardiovLas personas que más acomp edad de 45 años.añan son los hijos ás realizan los acompañantes son los relcionados con la subsistencia, como el baño y la alimentación, accioade sexo femenino, con promedio de Los cuidados que nes como la lectura, el juego y la música son realmizados sólo en el 10 por ciento en contraste con la conversación que es una de las acciones que más se realizan. La interacción del equipo de enfermería con el acompañante es mínima para casi todos los cuidados explorados en el estudio, se presentó la mayor interacción en la indicación, explicación y apoyo del baño. La auxiliar de enfermería es quien más interactúa con el acompañante en estas categorías; sobresale la poca interacción del profesional en enfermería. La educación, es impartida por el profesional de enfermería en mayor proporción; sin embargo, sólo se brinda al 11 por ciento del total de usuarios hospitalizados. Solo sí se penetra en el misterio del cuidado y se aborda profundamente el carácter humano y cultural de éste podemos trascender la relación con el usuario en términos de confianza, respeto y pertinencia con su familia y con el entorno social.


Subject(s)
Caregivers , Nursing Care , Nursing Services
17.
Haematologica ; 86(9): 934-40, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11532621

ABSTRACT

BACKGROUND AND OBJECTIVES: Bone marrow biopsies are routinely performed in the staging of patients with lymphoma. Despite the lack of evidence for its usefulness, many institutions include flow cytometry (FC) of bone-marrow aspirates in an attempt to increase sensitivity and specificity. The aim of this study is to evaluate the usefulness of FC for the assessment of bone-marrow involvement by lymphoma in follicular (FL) and diffuse large B-cell lymphomas (DLBCL). DESIGN AND METHODS: Seventy-nine bone marrow biopsies from 65 patients diagnosed with FL or DLBCL were examined to compare histology and FC for the assessment of bone-marrow involvement by lymphoma. RESULTS: Bone marrow histology showed involvement (BM+) in 16 cases (20.3%), lack of infiltration (BM(-)) in 52 cases (65.8%) and undetermined or undiagnosed for involvement (BMu) in 11 cases (13.9%). FC was positive for involvement in 28 cases (35.4%) and negative in 51 cases (64.6%). 65 cases (95%) showed concordance between the results of morphology and FC (BM(+)/FC(+) or BM(-)/FC(-)). No BM(+)/FC(-) cases were observed. 3 cases showed discrepant results (BM(-)/FC(+)). In these 3 cases the molecular studies (PCR) demonstrated clonal rearrangement of the heavy immunoglobulin chain (IgH) and/or bcl2-IgH in agreement with the flow results. Among the 11 cases with BMu, all but 2 were FC(+) and concordance with the PCR results was seen in 9 cases (81.9%). INTERPRETATION AND CONCLUSIONS: We conclude that FC is just as sensitive or perhaps slightly more sensitive than histology in the detection of bone marrow involvement in FL and DLBCL. FC studies may be warranted in those cases in which the morphology is not diagnosed. The clinical relevance of the small clonal B-cell population in patients without histologic bone marrow involvement (BM(-)/FC(+) cases) remains an open question.


Subject(s)
Bone Marrow/pathology , Flow Cytometry/standards , Lymphoma, Non-Hodgkin/pathology , Humans , Immunophenotyping , Lymphoma, B-Cell/diagnosis , Lymphoma, B-Cell/pathology , Lymphoma, Follicular/diagnosis , Lymphoma, Follicular/pathology , Lymphoma, Large B-Cell, Diffuse/diagnosis , Lymphoma, Large B-Cell, Diffuse/pathology , Lymphoma, Non-Hodgkin/diagnosis , Sensitivity and Specificity
18.
Rev. colomb. psiquiatr ; 30(3): 239-247, sept. 2001. tab, graf
Article in Spanish | LILACS | ID: lil-354667

ABSTRACT

Objetivos: Caracterizar una muestra de familias y tríos de una población colombiana aislada para mapear loci involucrados en la vulnerabilidad al Trastorno Afectivo Bipolar tipo I (TAB- I). Métodos: Se recolectan tríos y genealogías utilizando las entrevistas FIGS-DIGS en miembros de las familias y posibles afectados. El poder para detectar ligamiento (PDL) se estima por simulación. El modelo utilizado asume una frecuencia para el alelo afectado de 0.003, penetrancias de 0.01,0.81 y 0.9 y un marcador de cuatro alelos a 5cM del locus. Resultados: Se identificaron 28 familias con TAB-I, con 3.603 individuos y 160 afectados, y 246 tríos. Asumiendo homogeneidad genética y teniendo en cuenta la evidencia genética del mestizaje, las simulaciones mostraron PDL significativos de 100 por ciento para un LOD-score>3. Estamos examinando el desequilibrio promedio en tríos y tamizando en familias los cromosomas 12,18 y 21. Conclusión: Tenemos un grupo significativo de familias y trios pertenecientes a una población aislada con un poder para detectar ligamiento al Trastorno Afectivo Bipolar. Esto permite realizar estudios de ligamiento buscando genes involucrados en la vulnerabilidad al TAB-I en población Colombiana


Subject(s)
Bipolar Disorder
19.
Neurosci Lett ; 292(3): 199-202, 2000 Oct 13.
Article in English | MEDLINE | ID: mdl-11018311

ABSTRACT

The short variant of a functional length polymorphism in the promoter region of the serotonin transporter has been associated with several behavioural and psychiatric traits, including bipolar mood disorder. The same short allele has also been implicated as a modifier of the bipolar phenotype. Here we evaluate the etiologic/modifier role of this polymorphism in a case (N=103) / control (N=112) sample for bipolar mood disorder (type I) collected from an isolated South American population. We did not detect an association between bipolar disorder and the 5-HTT promoter polymorphism in this sample. However, an excess of the short allele was seen in younger cases and in cases with psychotic symptoms. When combined with data from the literature, the increased frequency of the short allele in patients with psychotic symptoms was statistically significant.


Subject(s)
Bipolar Disorder/genetics , Carrier Proteins/genetics , Membrane Glycoproteins/genetics , Membrane Transport Proteins , Nerve Tissue Proteins , Polymorphism, Genetic/genetics , Age of Onset , Alleles , Bipolar Disorder/epidemiology , Colombia/epidemiology , Gene Frequency , Genetic Linkage , Genetics, Population , Humans , Odds Ratio , Promoter Regions, Genetic/genetics , Serotonin Plasma Membrane Transport Proteins
20.
Med Clin (Barc) ; 111(10): 385-8, 1998 Oct 03.
Article in Spanish | MEDLINE | ID: mdl-9833242

ABSTRACT

BACKGROUND: Thrombotic Thrombocytopenic Purpura (TTP) is an uncommon clinical syndrome with high mortality rate in the absence of treatment. Despite the therapeutic efficacy of plasma exchange, patients often relapse even after long periods of time in remission. Over the last few years, late relapses in previously diagnosed patients have been seen in our hospital. PATIENTS AND METHODS: We analyzed retrospectively 22 episodes of TTP in 16 patients diagnosed during a four-year period. We reviewed the clinical features at diagnosis as well as the therapeutic results. In all but one, the treatment included daily plasma exchange. Other treatments, including vincristine, were also used in addition to plasma exchange, in 18 of 21 episodes. RESULTS: A complete remission was obtained in eighty-two percent of the episodes treated by plasma exchange. The median number of plasma exchange to achieve a complete remission was 6. In 4 episodes, 20 or more plasma exchange were required before achieving a satisfactory response. A complete remission was obtained in 78% of episodes where vincristine was used, versus 84% response rate in episodes where vincristine was not used. In four patients the cause death was directly related to TTP, while a fifth patients died of progressive lymphoma without evidence of TTP. Five of the eleven surviving patients relapsed with a median time to relapse of 24.6 months. Relapsing episodes presented with a less severe clinical picture including less clear signs of microangiopathic hemolytic anemia (MAHA), when compared with the initial ones. All patients in relapse responded promptly to treatment. The variables analyzed failed to predict either the response to treatment or the probability of relapse. CONCLUSIONS: The therapeutic efficacy of plasma exchange in the treatment of TTP has been demonstrated in our series as previously observed by many other groups. We have observed some slow responders where the prolongation of treatment by plasma exchange succeeded in achieving a complete remission. The use of vincristine did not show any therapeutical advantage in our experience.


Subject(s)
Purpura, Thrombotic Thrombocytopenic , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Purpura, Thrombotic Thrombocytopenic/diagnosis , Purpura, Thrombotic Thrombocytopenic/therapy , Recurrence , Retrospective Studies
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