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1.
Ann Oncol ; 29(1): 145-153, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29045530

RESUMEN

Background: Selection of resistance mutations may play a major role in the development of endocrine resistance. ESR1 mutations are rare in primary breast cancer but have high prevalence in patients treated with aromatase inhibitors (AI) for advanced breast cancer. We investigated the evolution of genetic resistance to the first-line AI therapy using sequential ctDNA sampling in patients with advanced breast cancer. Patients and methods: Eighty-three patients on the first-line AI therapy for metastatic breast cancer were enrolled in a prospective study. Plasma samples were collected every 3 months to disease progression and ctDNA analysed by digital droplet PCR and enhanced tagged-amplicon sequencing (eTAm-Seq). Mutations identified in progression samples by sequencing were tracked back through samples before progression to study the evolution of mutations on therapy. The frequency of novel mutations was validated in an independent cohort of available baseline plasma samples in the Study of Faslodex versus Exemestane with or without Arimidex (SoFEA) trial, which enrolled patients with prior sensitivity to AI. Results: Of the 39 patients who progressed on the first-line AI, 56.4% (22/39) had ESR1 mutations detectable at progression, which were polyclonal in 40.9% (9/22) patients. In serial tracking, ESR1 mutations were detectable median 6.7 months (95% confidence interval 3.7-NA) before clinical progression. Utilising eTAm-Seq ctDNA sequencing of progression plasma, ESR1 mutations were demonstrated to be sub-clonal in 72.2% (13/18) patients. Mutations in RAS genes were identified in 15.4% (6/39) of progressing patients (4 KRAS, 1 HRAS, 1 NRAS). In SoFEA, KRAS mutations were detected in 21.2% (24/113) patients although there was no evidence that KRAS mutation status was prognostic for progression free or overall survival. Conclusions: Cancers progressing on the first-line AI show high levels of genetic heterogeneity, with frequent sub-clonal mutations. Sub-clonal KRAS mutations are found at high frequency. The genetic diversity of AI resistant cancers may limit subsequent targeted therapy approaches.


Asunto(s)
Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , ADN Tumoral Circulante/genética , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/sangre , Neoplasias de la Mama/patología , ADN Tumoral Circulante/sangre , Progresión de la Enfermedad , Resistencia a Antineoplásicos/genética , Receptor alfa de Estrógeno/genética , Femenino , Humanos , Persona de Mediana Edad , Mutación , Metástasis de la Neoplasia , Estudios Prospectivos , Proteínas Proto-Oncogénicas p21(ras)/genética
2.
Mol Phylogenet Evol ; 94(Pt B): 827-832, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26432392

RESUMEN

Studies of caterpillar defense strategy evolution typically focus on aposematic coloration, gregarious behavior, and/or chemical defense. In the slug moth family Limacodidae, the evolution of chemical defense is coupled to the life history trait of first instar feeding behaviors. In nettle caterpillars, the first instars fast and molt into a second instar that feeds. In contrast, gelatines and monkey slug larval forms feed in the first instar. This study focused on whether the evolution of fasting associated with the nettle morphology was a derived trait of single or multiple origins. Twenty-nine species of Limacodidae (including one Chrysopolominae) representing 27 genera and four outgroup species with known first and final instar morphologies and behaviors were included. Four out-group species representing Megalopygidae (1 sp), Dalceridae (1 sp) and Aididae (2 sp) were included. These were sequenced for three molecular markers for a total of 4073 bp, mitochondrial COI (∼1500 bp), 18S (∼1900 bp) and the D2 region of 28S (approximately 670 bp). Maximum likelihood and Bayesian analyses were conducted. The resulting phylogeny and comparative analysis of feeding strategy revealed that the nettle caterpillar morphology and behavior of larval fasting may have a single origin.


Asunto(s)
Ayuno , Mariposas Nocturnas/fisiología , Animales , Evolución Biológica , Femenino , Larva/genética , Mariposas Nocturnas/genética , Fenotipo , Filogenia
3.
Front Allergy ; 5: 1297547, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38440401

RESUMEN

The allergenicity and protein risk assessments in food safety are facing new challenges. Demands for healthier and more sustainable food systems have led to significant advances in biotechnology, the development of more complex foods, and the search for alternative protein sources. All this has increased the pressure on the safety assessment prediction approaches anchored into requirements defined in the late 90's. In 2022, the EFSA's Panel on Genetically Modified Organisms published a scientific opinion focusing on the developments needed for allergenicity and protein safety assessments of new products derived from biotechnology. Here, we further elaborate on the main elements described in this scientific opinion and prioritize those development needs requiring critical attention. The starting point of any new recommendation would require a focus on clinical relevance and the development of a fit-for-purpose database targeted for specific risk assessment goals. Furthermore, it is imperative to review and clarify the main purpose of the allergenicity risk assessment. An internationally agreed consensus on the overall purpose of allergenicity risk assessment will accelerate the development of fit-for-purpose methodologies, where the role of exposure should be better clarified. Considering the experience gained over the last 25 years and recent scientific developments in the fields of biotechnology, allergy, and risk assessment, it is time to revise and improve the allergenicity safety assessment to ensure the reliability of allergenicity assessments for food of the future.

4.
Mol Psychiatry ; 17(8): 781-9, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21691274

RESUMEN

Interferon (IFN)-α treatment for infectious diseases and cancer is associated with significant depressive symptoms that can limit therapeutic efficacy. Multiple mechanisms have been implicated in IFN-α-induced depression including immune, neuroendocrine and neurotransmitter pathways. To further explore mechanisms of IFN-α-induced depression and establish associated genetic risk factors, single nucleotide polymorphisms in genes encoding proteins previously implicated in IFN-α-induced depression were explored in two self-reported ethnic groups, Caucasians (n=800) and African Americans (n=232), participating in a clinical trial on the impact of three pegylated IFN-α treatment regimens on sustained viral response in patients with chronic hepatitis C. Before treatment, all subjects were free of psychotropic medications and had a score ≤20 on the Center for Epidemiologic Studies Depression Scale (CES-D), which was used to assess depressive symptom severity throughout the study. In Caucasians, a polymorphism (rs9657182) in the promoter region of the gene encoding indoleamine-2,3-dioxygenase (IDO1) was found to be associated with moderate or severe IFN-α-induced depressive symptoms (CES-D>20) at 12 weeks of IFN-α treatment (P=0.0012, P<0.05 corrected). Similar results were obtained for treatment weeks 24, 36 and 48. In subjects homozygous for the risk allele (CC, n=150), the odds ratio for developing moderate or severe depressive symptoms at treatment week 12 was 2.91 (confidence interval: 1.48-5.73) compared with TT homozygotes (n=270). rs9657182 did not predict depression in African Americans, who exhibited a markedly lower frequency of the risk allele at this locus. The findings in Caucasians further support the notion that IDO has an important role in cytokine-induced behavioral changes.


Asunto(s)
Depresión/genética , Predisposición Genética a la Enfermedad/genética , Predisposición Genética a la Enfermedad/psicología , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Interferón-alfa/efectos adversos , Polietilenglicoles/efectos adversos , Adulto , Negro o Afroamericano/genética , Negro o Afroamericano/psicología , Alelos , Antivirales/efectos adversos , Depresión/complicaciones , Depresión/psicología , Femenino , Genotipo , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/psicología , Humanos , Interferón alfa-2 , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Regiones Promotoras Genéticas/genética , Escalas de Valoración Psiquiátrica , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/psicología , Proteínas Recombinantes/efectos adversos , Población Blanca/genética , Población Blanca/psicología
5.
Neuroimage ; 62(3): 1867-76, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22691613

RESUMEN

Analysis of neural oscillations in the electroencephalogram (EEG) during cognitive tasks provides valuable information about underlying neuronal processing not accessible by other methods such as event-related potentials (ERPs) and the BOLD signal in fMRI. We investigated neural substrates of motor preparation and expectancy by analyzing neural oscillations of healthy subjects performing the AX continuous performance task (AX-CPT), a task widely used to evaluate processes such as cognitive control, motor preparation and anticipatory and sustained attention. The task consists of letters presented sequentially on a monitor, and subjects are required to respond only when they see the letter A (cue) followed by the letter X (target). In this study, to emphasize expectation and motor preparation, three versions of AX-CPT were used in which the overall propensity to respond was differentially modulated, by changing the probability of the letter sequences. Neural activity was investigated in three time windows following presentation of the cue: sensory, evaluation and preparation. Alpha power was reduced following cue onset similarly in all versions of the task in both the sensory and evaluation periods, but in the later preparation period there were task dependent modulations. Alpha was decreased when an infrequent cue increased the chance of a response, and increased when a propensity to respond had to be overcome, possibly reflecting an anticipatory attentional mechanism to gate visuo-motor processing. Beta power was modulated by task and cue in both evaluation and preparation periods. In the latter, beta power reflected the propensity to respond and correlated both with amplitude of the contingent negative variation (CNV), an ERP that reflects response preparation, and with reaction time. Some clinical populations such as patients with schizophrenia or attention-deficit disorder show specific deficits when performing the AX-CPT. These results provide a basis for investigating the differential neural underpinnings of oscillatory cognitive control deficits observed in various patient populations.


Asunto(s)
Anticipación Psicológica/fisiología , Atención/fisiología , Encéfalo/fisiología , Función Ejecutiva/fisiología , Adolescente , Adulto , Señales (Psicología) , Electroencefalografía , Potenciales Evocados/fisiología , Femenino , Humanos , Masculino , Estimulación Luminosa , Desempeño Psicomotor/fisiología , Procesamiento de Señales Asistido por Computador , Adulto Joven
6.
Hum Reprod ; 27(4): 1202-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22298840

RESUMEN

BACKGROUND: The argument that women in stressful environments spontaneously abort their least fit fetuses enjoys wide dissemination despite the fact that several of its most intuitive predictions remain untested. The literature includes no tests, for example, of the hypothesis that these mechanisms select against small for gestational age (SGA) males. METHODS: We apply time-series modeling to 4.9 million California male term births to test the hypothesis that the rate of SGA infants in 1096 weekly birth cohorts varies inversely with labor market contraction, a known stressor of contemporary populations. RESULTS: We find support for the hypothesis that small size becomes less frequent among term male infants when the labor market contracts. CONCLUSIONS: Our findings contribute to the evidence supporting selection in utero. They also suggest that research into the association between maternal stress and adverse birth outcomes should acknowledge the possibility that fetal loss may affect findings and their interpretation. Strengths of our analyses include the large number and size of our birth cohorts and our control for autocorrelation. Weaknesses include that we, like nearly all researchers in the field, have no direct measure of fetal loss.


Asunto(s)
Aborto Espontáneo/epidemiología , Economía , Recién Nacido Pequeño para la Edad Gestacional , Estrés Psicológico , Peso al Nacer , California/epidemiología , Estudios de Cohortes , Empleo/psicología , Femenino , Humanos , Recién Nacido , Masculino , Modelos Biológicos , Embarazo , Resultado del Embarazo , Selección Genética , Factores Socioeconómicos
7.
Artículo en Inglés | MEDLINE | ID: mdl-35027061

RESUMEN

BACKGROUND: The impacts of the COVID-19 pandemic have been vast and are not limited to physical health. Many adolescents have experienced disruptions to daily life, including changes in their school routine and family's financial or emotional security, potentially impacting their emotional wellbeing. In low COVID-19 prevalence settings, the impact of isolation has been mitigated for most young people through continued face-to-face schooling, yet there may still be significant impacts on their wellbeing that could be attributed to the pandemic. METHODS: We report on data from 32,849 surveys from Year 7-12 students in 40 schools over two 2020 survey cycles (June/July: 19,240; October: 13,609), drawn from a study of 79 primary and secondary schools across Western Australia, Australia. The Child Health Utility Index (CHU9D) was used to measure difficulties and distress in responding secondary school students only. Using comparable Australian data collected six years prior to the pandemic, the CHU9D was calibrated against the Kessler-10 to establish a reliable threshold for CHU9D-rated distress. RESULTS: Compared to 14% of responding 12-18-year-olds in 2013/2014, in both 2020 survey cycles almost 40% of secondary students returned a CHU9D score above a threshold indicative of elevated difficulties and distress. Student distress increased significantly between June and October 2020. Female students, those in older Grades, those with few friendships or perceived poor quality friendships, and those with poor connectedness to school were more likely to score above the threshold. CONCLUSIONS: In a large dataset collected during the first year of the COVID-19 pandemic, the proportion of secondary school students with scores indicative of difficulties and distress was substantially higher than a 2013/2014 benchmark, and distress increased as the pandemic progressed, despite the low local prevalence of COVID-19. This may indicate a general decline in social and emotional wellbeing exacerbated by the events of the pandemic. TRIAL REGISTRATION: ANZCTRN (ACTRN12620000922976). Retrospectively registered 17/08/2020. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=380429&isReview=true .

8.
Phys Rev Lett ; 107(26): 262501, 2011 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-22243152

RESUMEN

The (2)H(e,e'p)n cross section at a momentum transfer of 3.5 (GeV/c)(2) was measured over a kinematical range that made it possible to study this reaction for a set of fixed missing momenta as a function of the neutron recoil angle θ(nq) and to extract missing momentum distributions for fixed values of θ(nq) up to 0.55 GeV/c. In the region of 35°≤θ(nq)≤45° recent calculations, which predict that final-state interactions are small, agree reasonably well with the experimental data. Therefore, these experimental reduced cross sections provide direct access to the high momentum component of the deuteron momentum distribution in exclusive deuteron electrodisintegration.

9.
J Med Ethics ; 37(2): 109-12, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20962065

RESUMEN

Dan Brock argues that since the unexploitable rich could sell their kidneys too, exploitation could not be an essential feature of organ vending. This paper takes his claim as the point of departure for a discussion on the locus of organ vending-associated oppression. While it accepts Brock's conclusion, it explores the possibility that such oppression is invariably found rather outside the sphere of exchange. It then analyses the implications of this possibility for the discourse surrounding the ethics of organ vending.


Asunto(s)
Donadores Vivos/psicología , Trasplante de Órganos/ética , Obtención de Tejidos y Órganos/ética , Comercio/ética , Femenino , Humanos , Masculino , Trasplante de Órganos/economía , Trasplante de Órganos/psicología , Trasplante de Páncreas/economía , Trasplante de Páncreas/ética , Trasplante de Páncreas/psicología , Factores Socioeconómicos , Obtención de Tejidos y Órganos/economía
10.
J Econ Entomol ; 104(5): 1706-19, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22066202

RESUMEN

A molecular assay for diagnosis of light brown apple moth, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), in North America is reported. The assay multiplexes two TaqMan real-time polymerase chain reaction (RT-PCR) probe systems that are designed to target DNA segments of the internal transcribed spacer region 2 (ITS2) and 18S rRNA gene. The RT-PCR probe designed for the 18S target recognizes a DNA sequence conserved in all of the moths included in the study and functions as a control in the assay. The second probe recognizes a segment of the ITS2 specifically found in E. postvittana and not found in the other moths included in the study, i.e., this segment is not conserved. Inclusion of the two markers in a single multiplex reaction did not affect assay performance. The assay was tested against 637 moths representing > 90 taxa in 15 tribes in all three subfamilies in the Tortricidae. The assay generated no false negatives based on analysis of 355 E. postvittana collected from California, Hawaii, England, New Zealand, and Australia. Analysis of a data set including 282 moths representing 41 genera generated no false positives. Only three inconclusive results were generated from the 637 samples. Spike experiments demonstrated that DNA contamination in the assay can affect samples differently. Contaminated samples analyzed with the ITS2 RT-PCR assay and DNA barcode methodology by using the cytochrome oxidase I gene can generate contradictory diagnoses.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , Mariposas Nocturnas/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Animales , California , Complejo IV de Transporte de Electrones/genética , Marcadores Genéticos , Datos de Secuencia Molecular , Mariposas Nocturnas/clasificación , América del Norte , ARN Ribosómico 18S/genética , Alineación de Secuencia
11.
J Exp Med ; 158(2): 280-93, 1983 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-6193217

RESUMEN

Epstein-Barr (EB) virus-specific effector T cell lines were established from nine virus-immune donors positive for the serologically defined HLA-A2 antigen; of these, four lines contained a demonstrable A2-restricted cytotoxic component. When these four effector populations were each tested on the same panel of EB virus-transformed lines from 20 HLA-A2-positive individuals, 16 of the target cell lines were consistently killed at levels above 25% of the relevant autologous cell lysis. Cytotoxicity appeared to be mediated through a restricting determinant associated with the 'common A2' antigen that these lines shared; indeed the lysis could be specifically blocked by high concentrations of an HLA-A2-specific monoclonal antibody. In contrast, 4 out of 20 target cell lines were not killed by HLA-A2-restricted effector cells, even though they did express the serologically defined A2 antigen and were found in other tests to be susceptible to EB virus-specific cytolysis restricted through other HLA-A or -B antigens on their surface. These results suggest that EB virus-specific cytotoxic T cells can distinguish between serologically identical HLA-A2 molecules via the heterogeneity of their T cell-restricting determinants. Data from one of the effector cell populations further suggested that a serologically defined cross-reaction between the otherwise distinct HLA-A2 and -Bw57 antigens might also be reflected in a cross-reactivity of T cell-restricting determinants.


Asunto(s)
Antígenos HLA/genética , Infecciones por Herpesviridae/inmunología , Polimorfismo Genético , Linfocitos T Citotóxicos/inmunología , Adulto , Anticuerpos Monoclonales/inmunología , Unión Competitiva , Transformación Celular Viral , Reacciones Cruzadas , Citotoxicidad Inmunológica , Epítopos/genética , Antígenos HLA/análisis , Antígenos HLA/inmunología , Antígeno HLA-A2 , Antígenos HLA-B , Herpesvirus Humano 4/inmunología , Humanos
12.
J Exp Med ; 158(6): 1804-21, 1983 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-6196431

RESUMEN

Epstein-Barr (EB) virus-specific cytotoxic T cells, prepared from virus-immune donors by reactivation in vitro and maintained thereafter as IL-2-dependent T cell lines, have been tested against large panels of EB virus-transformed lymphoblastoid cell lines of known HLA type. Whilst the pattern of lysis of the majority of targets was always consistent with HLA-A and HLA-B antigen restriction of effector function, in several cases it was noticed that certain HLA-mismatched targets were also reproducibly lysed. When this "anomalous" lysis was investigated in detail, it was found to be directed against allodeterminants on class I HLA antigens; thus, mitogen-stimulated as well as EB virus-transformed lymphoblasts from the relevant target cell donors were sensitive to the killing, and in each case the lysis could be specifically blocked by monoclonal antibodies to class I HLA antigens. In one example the target for this alloreactive lysis could be identified as a single serologically defined antigen, HLA-Bw57, while in another example lysis was directed against a "public" epitope common to HLA-Bw35, -Bw62, and a subset of -B12 antigens. Both cold target inhibition experiments and limiting dilution analysis strongly suggested that this alloreactive lysis was being mediated by the same effector T cells that recognize EB viral antigens in the context of self-HLA. This is the first demonstration in man that alloreactive responses can be derived from within the antigen-specific, self MHC-restricted T cell repertoire.


Asunto(s)
Antígenos HLA/inmunología , Herpesvirus Humano 4/inmunología , Linfocitos T Citotóxicos/inmunología , Anticuerpos Monoclonales , Línea Celular , Reacciones Cruzadas , Citotoxicidad Inmunológica , Epítopos , Humanos , Isoantígenos/inmunología
13.
J Exp Med ; 182(4): 915-22, 1995 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-7561694

RESUMEN

B cells are an abundant population of lymphocytes that can efficiently capture, process, and present antigen for recognition by activated or memory T cells. Controversial experiments and arguments exist, however, as to whether B cells are or should be involved in the priming of virgin T cells in vivo. Using B cell-deficient mice, we have studied the role of B cells as antigen-presenting cells in a wide variety of tests, including assays of T cell proliferation and cytokine production in responses to protein antigens, T cell killing to minor and major histocompatibility antigens, skin graft rejection, and the in vitro and in vivo responses to shistosome eggs. We found that B cells are not critical for either CD4 or CD8 T cell priming in any of these systems. This finding lends support to the notion that the priming of T cells is reserved for specialized cells such as dendritic cells and that antigen presentation by B cells serves distinct immunological functions.


Asunto(s)
Presentación de Antígeno , Células Presentadoras de Antígenos/inmunología , Linfocitos B/inmunología , Activación de Linfocitos , Linfocitos T/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Citocinas/análisis , Femenino , Técnica del Anticuerpo Fluorescente , Cadenas mu de Inmunoglobulina/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Esquistosomiasis mansoni/inmunología , Trasplante de Piel
14.
Clin Exp Allergy ; 40(4): 650-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19958367

RESUMEN

BACKGROUND: One of the concerns of allergen-specific immunotherapy is the possible boost of inflammatory allergen-specific T lymphocytes. To address this problem, treatment with B cell epitopes devoid of allergen-specific T cell epitopes would be a promising alternative. OBJECTIVE: In this study, we examined the therapeutic potency of a single mimotope, mimicking a structural IgE epitope of grass pollen allergen Phl p 5 in an established memory mouse model of acute allergic asthma. METHODS: In the experimental set-up, BALB/c mice were primed with intraperitoneal injections of recombinant Phl p 5a (rPhl p 5a) and subsequently aerosol challenged with the nebulized allergen. Mice developed signs of bronchial asthma including hypereosinophilia around bronchi, goblet cell hyperplasia and enhanced mucus production. RESULTS: When the mice were subsequently treated with the grass pollen mimotope coupled to keyhole limpet haemocyanin, bronchial eosinophilic inflammation and mucus hypersecretion decreased. Further, a decrease of Th2 cytokines IL-4 and IL-5 could be observed in the bronchoalveolar lavage (BAL). In contrast to rPhl p 5a, the mimotope was in vitro not able to stimulate splenocytes to proliferation or IL-5 production. Despite not affecting the levels of pre-existing IgE, vaccination with the single mimotope thus rendered anti-inflammatory effects in a mouse model of acute asthma. CONCLUSION: From our data, we conclude that vaccination with a mimotope peptide representing a single IgE epitope of the allergen Phl p 5a and being devoid of allergen-specific T cell epitopes is able to down-regulate inflammation in acute asthma.


Asunto(s)
Asma , Epítopos de Linfocito T , Inmunoglobulina E/inmunología , Imitación Molecular , Proteínas de Plantas , Hipersensibilidad Respiratoria , Animales , Asma/inmunología , Asma/terapia , Modelos Animales de Enfermedad , Epítopos de Linfocito T/administración & dosificación , Epítopos de Linfocito T/química , Epítopos de Linfocito T/inmunología , Femenino , Humanos , Inflamación/inmunología , Inflamación/terapia , Ratones , Ratones Endogámicos BALB C , Proteínas de Plantas/administración & dosificación , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/inmunología , Hipersensibilidad Respiratoria/inmunología , Hipersensibilidad Respiratoria/terapia , Resultado del Tratamiento , Vacunación
15.
Hippokratia ; 24(3): 107-113, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-34239287

RESUMEN

INTRODUCTION: Fiscal federalism and fiscal decentralization are distinct policy options in public services in general and healthcare in particular, with possibly opposed effects on equity, effectiveness, and efficiency. However, the pertinent discourse often reflects confusion between the concepts or conflation thereof. METHODS: This paper performs a narrative review of theoretical literature on decentralization. The study offers clear definitions of the concepts of fiscal federalism and fiscal decentralization and provides an overview of the potential implications of each policy for healthcare systems. RESULTS: The interpretation of the literature identified three different dimensions of decentralization: political, administrative, economic. Economic decentralization can be further implemented through two different policy options: fiscal federalism and fiscal decentralization. Fiscal federalism is the transfer of spending authority of a centrally pooled public health budget to local governments or authorities. Countries like the UK, Cuba, Denmark, and Brazil mostly rely on fiscal federalism mechanisms for healthcare financing. Fiscal decentralization consists of transferring both pooling and spending responsibilities from the central government to local authorities. Contrarily to fiscal federalism, the implementation of fiscal decentralization requires as a precondition the fragmentation of the national pool into many local pools. The restructuring of the pooling system may limit the cross-subsidization effect between high- and low-income groups and areas that a central pool guarantees; thus, severely affecting local equality and equity. With the limited availability of local public resources in poorer regions, the quality of services drops, increasing the disparity gap between areas. Evidence from Italy, Spain, China, and Ivory Coast -countries with a strong fiscal decentralization element in their healthcare services- suggests that fiscal decentralization has positive effects on the infant mortality rate. However, it decreases healthcare resources as well as access to services, fostering spatial inequities. CONCLUSION: If public resources are and remain adequate, allocation follows equitable criteria, and local communities are involved in the decision-making debate, fiscal federalism -rather than fiscal decentralization- appear to be an adequate policy option to improve the healthcare services and population's health nationwide and achieve health sector economic decentralization. HIPPOKRATIA 2020, 24(3): 107-113.

16.
J Cell Biol ; 75(3): 769-87, 1977 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-562887

RESUMEN

We have examined the specificity of communication between cells in culture by co-culturing cells derived from mammalian, avian, and arthropod organisms. Both mammalian and avian culture cells have similar gap junctional phenotypes, while the insect (arthropod) cell lines have a significantly different gap junctional structure. Electrophysiological and ultrastructural methods were used to examine ionic coupling and junctional interactions between homologous and heterologous cell types. In homologous cell systems, gap junctions and ionic coupling are present at a high incidence. Also, heterologous vertebrate cells in co-culture can communicate readily. By contrast, practically no coupling (0-8%) is detectable between heterologous insect cell lines (Homopteran or Lepidopteran) and vertebrate cells (mammalian myocardial or 3T3 cells). No gap junctions have been observed between arthropod and vertebrate cell types, even though the heterologous cells may be separated by less than 10 nm. In additional studies, a low incidence of coupling was found between heterologous insect cell lines derived from different arthropod orders. However, extensive coupling was detected between insect cell lines that are derived from the same order (Homoptera). These observations suggest that there is little or no apparent specificity for communication between vertebrate cells in culture that express the same gap junctional phenotype, while there is a definite communication specificity that exists between arthropod cells in culture.


Asunto(s)
Comunicación Celular , Uniones Intercelulares/fisiología , Animales , Línea Celular , Embrión de Pollo , Dípteros , Electrofisiología , Insectos , Uniones Intercelulares/ultraestructura , Lepidópteros , Ratones , Especificidad de la Especie
17.
J Cell Biol ; 75(3): 788-806, 1977 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-925080

RESUMEN

Cell-to-cell communication was characterized in prefusion chick embryo myoblast cultures, and it was determined that the prefusion myoblasts can interact via gap junctions, ionic coupling, and metabolic coupling. The biological relevance of this communication was supported by the detection of gap junctions between myoblasts in embryonic muscle. Communication was also examined in fusion-arrested cultures to determine its potential relationship to fusion competency. In cultures that were fusion arrested by treatment with either 1.8 mM ethyleneglycolbis-(beta-aminoethyl ether)N,N'-tetraacetic acid (EGTA), 3.3 X 10(-6) M 5-bromodeoxyuridine (BUdR), or 1 microgram/ml cycloheximide (CHX), both gap junctions and ionic coupling were present. Therefore, it is possible to conclude that cell communication is not a sufficient property by itself, to generate fusion between myob-asts. The potential role of communication in myogenesis is discusssed with respect to these observations.


Asunto(s)
Comunicación Celular , Uniones Intercelulares/fisiología , Músculos/citología , Diferenciación Celular , Fusión Celular , Células Cultivadas , Electrofisiología , Uniones Intercelulares/ultraestructura , Uridina/metabolismo
18.
J Cell Biol ; 78(1): 58-75, 1978 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-670298

RESUMEN

Cell-to-cell communication was characterized in cumulus-oocyte complexes from rat ovarian follicles before and after ovulation. Numerous, small gap junctional contacts were present between cumulus cells and oocytes before ovulation. The gap junction are formed on the oocyte surface by cumulus cell processes that transverse the zona pellucida and contact the oolemma. The entire cumulus mass was also connected by gap junctions via cumulus-cumulus interactions. In the hours preceding ovulation, the frequency of gap junctional contacts between cumulus cells and the oocyte was reduced, and the cumulus was disorganized. Electrophysiological measurements indicated that bidirectional ionic coupling was present between the cumulus and oocyte before ovulation. In addition, iontophoretically injected fluorescein dye was tranferred between the oocyte and cumulus cells. Examination of the extent of ionic coupling in cumulus-oocyte specimens before and after ovulation revealed that ionic coupling between the cumulus and oocyte progressively decreased as the time of ovulation approached. In postovulatory specimens, no coupling was detected. Although some proteolytic mechanism may be involved in the disintegration of the cumulus-oocyte complex, neither the cumulus cells nor the oocyte produced detectable levels of plasminogen activator, a protease which is synthesized by membrana granulosa cells. In summary, cell communication is a characterisitc feature of the cumulus-oocyte complex, and this communication is terminated near the time of ovulation. This temporal pattern of the termination of communication between the cumulus and the oocyte may indicate that communication provides a mechanism for regulating the maturation of the oocyte during follicular development before ovulation.


Asunto(s)
Comunicación Celular , Células de la Granulosa/fisiología , Oocitos/fisiología , Ovulación , Óvulo/fisiología , Animales , Membrana Celular/ultraestructura , Femenino , Fluoresceínas/metabolismo , Células de la Granulosa/ultraestructura , Uniones Intercelulares/ultraestructura , Potenciales de la Membrana , Oocitos/ultraestructura , Activadores Plasminogénicos/metabolismo , Ratas
19.
Science ; 210(4467): 280-5, 1980 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-7423188

RESUMEN

Optical fibers transmit high-intensity illumination for viewing internal organs and tissue. Remote viewing is obtained by relays of lenses or graded-index-of-refraction rods in rigid endoscopes and by precisely aligned fiber-optic bundles in flexible fiberscopes. Endoscopy is considered for routine examinations, such as in colonoscopy. Lasers are used as surgical tools through endoscopes for cutting and coagulation. They may also be used to provide illumination for the efficient transmission of light through thin optical fibers.


Asunto(s)
Endoscopios , Colonoscopios , Colonoscopía/efectos adversos , Tecnología de Fibra Óptica/instrumentación , Humanos , Rayos Láser , Iluminación , Fibras Ópticas
20.
Science ; 175(4018): 202-3, 1972 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-4332762

RESUMEN

Human embryo fibroblasts have undergone morphological transformation in vitro after infection by Epstein-Barr virus. The fibroblasts were maintained in suspension during exposure to the virus, and further treatment with inactivated Sendai virus increased the transformation rate. The transformed cells were large and polygonal and grew in discrete, heaped up, foci.


Asunto(s)
Transformación Celular Neoplásica , Herpesviridae , Células Cultivadas , Embrión de Mamíferos , Fibroblastos/citología , Herpesvirus Humano 4 , Humanos , Virus de la Parainfluenza 1 Humana
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