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1.
Glob Chang Biol ; 30(1): e16991, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37905464

RESUMEN

Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could mitigate impacts from increases in ambient temperatures (from 1.5 to 3°C in air temperatures and from 1.4 to 2.3°C in sea surface temperatures by 2100 at our sites) on four species of sea turtles, under a "middle of the road" scenario (SSP2-4.5). Sand temperatures at sea turtle nesting sites are projected to increase from 0.58 to 4.17°C by 2100 and expected shifts in nesting of 26-43 days earlier will not be sufficient to maintain current incubation temperatures at 7 (29%) of our sites, hatching success rates at 10 (42%) of our sites, with current trends in hatchling sex ratio being able to be maintained at half of the sites. We also calculated the phenological shifts that would be required (both backward for an earlier shift in nesting and forward for a later shift) to keep up with present-day incubation temperatures, hatching success rates, and sex ratios. The required shifts backward in nesting for incubation temperatures ranged from -20 to -191 days, whereas the required shifts forward ranged from +54 to +180 days. However, for half of the sites, no matter the shift the median incubation temperature will always be warmer than the 75th percentile of current ranges. Given that phenological shifts will not be able to ameliorate predicted changes in temperature, hatching success and sex ratio at most sites, turtles may need to use other adaptive responses and/or there is the need to enhance sea turtle resilience to climate warming.


Asunto(s)
Tortugas , Animales , Tortugas/fisiología , Temperatura , Cambio Climático , Reproducción , Razón de Masculinidad
2.
J Public Health (Oxf) ; 42(2): 395-402, 2020 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-32166309

RESUMEN

BACKGROUND: Heatwaves can lead to increased mortality. In the Portuguese heat-health warning system (HHWS), ÍCARO, a daily report with heat-related mortality prediction is sent to heat-health action plan (HHAP) practitioners. HHAP practitioners assess risk and implement measures to prevent heatwave-related impact, but ÍCARO's use and understanding are unknown. We assessed ÍCARO's use and understanding by key HHAP practitioners. METHODS: We conducted semi-structured interviews with national/regional HHAP practitioners. Interviews were recorded, transcribed and analysed using thematic content analysis. To maximize credibility a validation process was implemented through researcher triangulation; a sample of 30 segments was recorded by independent researchers. RESULTS: We conducted six interviews with nine professionals (mean time 52 min) from five regions. We identified four categories: report's content and presentation, report's reception and communication, ÍCARO and risk assessment and other issues. Practitioners use ÍCARO and perceived it as relevant; they raised issues on its interpretation and felt these were not fully addressed, given researchers' use of statistical/epidemiological terms. We identified the need for improved communication and report's clarity. CONCLUSIONS: Our study stresses the need for collaboration between experts within HHWS/HHAP. Despite ÍCARO's understanding being challenging, practitioners consider it a relevant tool. Researchers should use less statistical language and clarify ÍCARO's interpretation. Practitioners' needs should be considered when developing/revising tools.


Asunto(s)
Calor , Lenguaje , Comunicación , Planificación en Salud , Humanos , Portugal
3.
Rev Clin Esp ; 2020 May 30.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32782069

RESUMEN

Deep vein thrombosis of the lower extremities is a common condition that should be treated appropriately given the possibility that it could lead to an ultimately fatal complication, as well as to a post-thrombotic syndrome that is in some cases disabling. The current treatment for this condition is differentiated into an acute phase, a long-term therapy and occasionally an extended therapy, which not only has defined objectives but also uses various drugs and even varying dosages for each drug. We describe the therapeutic anticoagulation options in each of these treatment phases and some of the treatments (thrombolysis, insertion of an inferior vena cava filter, surgery) that can play a role in certain conditions.

4.
Mol Phylogenet Evol ; 140: 106569, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31362083

RESUMEN

Phylogenetic niche conservatism (PNC) shapes the distribution of organisms by constraining lineages to particular climatic conditions. Conversely, if areas with similar climates are geographically isolated, diversification may also be limited by dispersal. Neotropical xeric habitats provide an ideal system to test the relative roles of climate and geography on diversification, as they occur in disjunct areas with similar biotas. Sicariinae sand spiders are intimately associated with these xeric environments, particularly seasonally dry tropical forests (SDTFs) and subtropical deserts/scrublands in Africa (Hexophthalma) and the Neotropics (Sicarius). We explore the role of PNC, geography and biome shifts in their evolution and timing of diversification. We estimated a time-calibrated, total-evidence phylogeny of Sicariinae, and used published distribution records to estimate climatic niche and biome occupancy. Topologies were used for estimating ancestral niches and biome shifts. We used variation partitioning methods to test the relative importance of climate and spatially autocorrelated factors in explaining the spatial variation in phylogenetic structure of Sicarius across the Neotropics. Neotropical Sicarius are ancient and split from their African sister-group around 90 (57-131) million years ago. Most speciation events took place in the Miocene. Sicariinae records can be separated in two groups corresponding to temperate/dry and tropical/seasonally dry climates. The ancestral climatic niche of Sicariinae are temperate/dry areas, with 2-3 shifts to tropical/seasonally dry areas in Sicarius. Similarly, ancestral biomes occupied by the group are temperate and dry (deserts, Mediterranean scrub, temperate grasslands), with 2-3 shifts to tropical, seasonally dry forests and grasslands. Most of the variation in phylogenetic structure is explained by long-distance dispersal limitation that is independent of the measured climatic conditions. Sicariinae have an ancient association to arid lands, suggesting that PNC prevented them from colonizing mesic habitats. However, niches are labile at a smaller scale, with several shifts from deserts to SDTFs. This suggests that PNC and long-distance dispersal limitation played major roles in confining lineages to isolated areas of SDTF/desert over evolutionary history, although shifts between xeric biomes occurred whenever geographical opportunities were presented.


Asunto(s)
Clima Desértico , Ecosistema , Bosques , Filogenia , Arañas/clasificación , Clima Tropical , África , Animales , Biodiversidad , Geografía
5.
Epidemiol Infect ; 145(9): 1786-1796, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28434418

RESUMEN

Societal and economic impact of influenza is mainly due to influenza infection of specific groups, who are at higher risk of health complications leading up to hospitalisation or death. In this study we applied the health belief model (HBM) to evaluate beliefs and attitudes towards influenza disease and vaccine in community-dwelling high-risk individuals (aged 65 or more or having a chronic disease). We conducted a mixed-method study using data collected through a telephone survey of a household unit sample. We used thematic analysis to map responses to HBM dimensions and Poisson regression to model vaccine non-uptake prevalence. The main self-reported reason not to take the vaccine referred to the susceptibility dimension: 'considering oneself to be a healthy person' (29·8%, (95% confidence interval (CI) 22·1-38·7)). Bad experiences after vaccination - barriers dimension - were also commonly reported (17·0%, (95% CI 10·8-23·8)). Vaccine non-uptake prevalence was 22% higher in those who did not consider themselves susceptible to contract flu (Prevalence Ratio (PR) = 1·22, (95% CI 1·0-1·5)) and 18% lower in those who did not consider that the vaccine causes flu symptoms (PR = 0·82, (95% CI 0·68-0·99)). Results suggest that high-risk individuals do not think of themselves susceptible to influenza infection and fear adverse events following immunisation.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Vacunas contra la Influenza , Gripe Humana/psicología , Vacunación/psicología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Portugal , Vacunación/estadística & datos numéricos , Adulto Joven
6.
Food Chem ; 426: 136606, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37356238

RESUMEN

Vitamins are a vast group of fundamental organic compounds, which are not produced by the human body but are essential for the living organisms' good health. Vitamins B6 and B12 belong to the same group of hydrophilic vitamins. Structurally unrelated, they share the same purpose as essential components for normal cellular operation, growth and development. Vitamin B6 is an enzymatic co-factor that is vital for countless biochemical reactions, and is also important in sugar and fatty acid metabolization. It encompasses three natural and inter-convertible pyridine-derivatives: pyridoxine, pyridoxal and pyridoxamine. Vitamin B12 is a cobalt organometallic complex also indispensable in numerous human physiological functions. It has four bioactive forms: cyanocobalamin, methylcobalamin, hydroxocobalamin and 5'-deoxyadenosylcobalamin, and only a few prokaryotes have the ability to biosynthesize cobalamin. This work reviews the significant aspects of vitamins B6 and B12: their vital roles, consequences of deficit; food sources; and methods of determination and respective matrices, with heavy emphasis on chromatographic techniques developed within the last two decades.


Asunto(s)
Piridoxina , Vitamina B 6 , Humanos , Piridoxina/análisis , Prevalencia , Piridoxal , Vitaminas , Vitamina B 12
7.
Scand J Immunol ; 76(6): 567-72, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22946764

RESUMEN

The mitogenic lectins are invaluable tools to study the biochemical changes associated with lymphocyte activation and proliferation of various immune cells. Rachycentron canadum lectin (RcaL) was detected and purified from serum of cobia fish. The aim of this study was to evaluate the proliferative response and cytokine production in splenocytes of mice in vitro stimulated with RcaL lectin; Canavalia ensiformis lectin (Con A) was used as positive control. A high proliferation index was induced by RcaL in relation to control cells. Furthermore, RcaL induced higher IL-2 and IL-6 production in relation to control. The cell viability was 90% in splenocytes treated with RcaL lectin, but RcaL promoted significant late apoptosis after 24 and 48 h in relation to control. RcaL induced proliferative responses suggesting that this lectin can be used as a mitogenic agent in immunostimulatory assays.


Asunto(s)
Lectinas/farmacología , Mitógenos/farmacología , Bazo/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Inmunización , Técnicas Inmunológicas , Interleucina-2/metabolismo , Interleucina-6/metabolismo , Lectinas/sangre , Lectinas/aislamiento & purificación , Ratones , Ratones Endogámicos BALB C , Perciformes/sangre , Lectinas de Plantas/farmacología , Bazo/inmunología
8.
Oper Dent ; 36(5): 521-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21819199

RESUMEN

This study was designed to evaluate in vitro the efficacy of a novel at-home bleaching technique using 10% or 16% carbamide peroxide modified by casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and its influence on the microhardness of bleached enamel. A total of 40 bovine incisors were divided into four groups (n=10) according to the bleaching agent used: 10% carbamide peroxide only; a blend of 10% carbamide peroxide and a CPP-ACP paste; 16% carbamide peroxide only; and a blend of 16% carbamide peroxide and a CPP-ACP paste. During the 14-day bleaching regimen, the samples were stored in artificial saliva. The Vickers microhardness and color of the teeth were assessed at baseline (T0) and immediately after the bleaching regimen (T14) using a microhardness tester and a spectrophotometer, respectively. The degree of color change was determined by the Commission Internationale de l'Eclariage (CIE) L*a*b* system (ΔE, ΔL*, Δa*, and Δb*) and Vita shade guide parameters. The data were analyzed by analysis of variance and the Tukey test (p<0.05). The teeth that were bleached with a blend of peroxide (10% or 16%) and the CPP-ACP paste presented increased microhardness values at T14 compared with T0, whereas the samples that were bleached with peroxide only did not show any differences in their microhardness values. All of the bleaching agents were effective at whitening the teeth and did not show a statistically significant difference using the CIEL*a*b* system (ΔE, ΔL*, Δa*, and Δb*) or the Vita shade guide parameters. The use of a CPP-ACP paste with carbamide peroxide bleaching agents increased the bleached enamel's microhardness and did not have an influence on whitening efficacy.


Asunto(s)
Cariostáticos/uso terapéutico , Caseínas/uso terapéutico , Esmalte Dental/efectos de los fármacos , Peróxidos/uso terapéutico , Blanqueadores Dentales/uso terapéutico , Blanqueamiento de Dientes/métodos , Urea/análogos & derivados , Óxido de Aluminio/química , Animales , Peróxido de Carbamida , Cariostáticos/administración & dosificación , Caseínas/administración & dosificación , Bovinos , Color , Esmalte Dental/patología , Grabado Dental/métodos , Dureza , Concentración de Iones de Hidrógeno , Ensayo de Materiales , Peróxidos/administración & dosificación , Distribución Aleatoria , Saliva Artificial/química , Espectrofotometría , , Temperatura , Factores de Tiempo , Blanqueadores Dentales/administración & dosificación , Decoloración de Dientes/tratamiento farmacológico , Decoloración de Dientes/patología , Urea/administración & dosificación , Urea/uso terapéutico , Vino
10.
J Exp Med ; 188(7): 1333-42, 1998 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-9763612

RESUMEN

Ship is an Src homology 2 domain containing inositol polyphosphate 5-phosphatase which has been implicated as an important signaling molecule in hematopoietic cells. In B cells, Ship becomes associated with Fcgamma receptor IIB (FcgammaRIIB), a low affinity receptor for the Fc portion of immunoglobulin (Ig)G, and is rapidly tyrosine phosphorylated upon B cell antigen receptor (BCR)-FcgammaRIIB coligation. The function of Ship in lymphocytes was investigated in Ship-/- recombination-activating gene (Rag)-/- chimeric mice generated from gene-targeted Ship-/- embryonic stem cells. Ship-/-Rag-/- chimeras showed reduced numbers of B cells and an overall increase in basal serum Ig. Ship-/- splenic B cells displayed prolonged Ca2+ influx, increased proliferation in vitro, and enhanced mitogen-activated protein kinase (MAPK) activation in response to BCR-FcgammaRIIB coligation. These results demonstrate that Ship plays an essential role in FcgammaRIIB-mediated inhibition of BCR signaling, and that Ship is a crucial negative regulator of Ca2+ flux and MAPK activation.


Asunto(s)
Linfocitos B/metabolismo , Monoéster Fosfórico Hidrolasas/fisiología , Receptores de Antígenos de Linfocitos B/metabolismo , Transducción de Señal , Animales , Linfocitos B/inmunología , Calcio/metabolismo , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , División Celular , Citocinas/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/fisiología , Inmunoglobulinas/sangre , Ratones , Ratones Noqueados , Proteína Quinasa 1 Activada por Mitógenos , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas , Monoéster Fosfórico Hidrolasas/genética , Fosforilación , Receptores de IgG/metabolismo , Linfocitos T/citología , Células TH1/metabolismo , Células Th2/metabolismo , Virus de la Estomatitis Vesicular Indiana/inmunología
11.
J Exp Med ; 186(6): 941-53, 1997 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-9294148

RESUMEN

The dual specific kinase SAPK/ERK1 kinase (SEK1; mitogen-activated protein kinase kinase 4/Jun NH2 terminal kinase [ JNK] kinase) is a direct activator of stress-activated protein kinases ([SAPKs]/JNKs) in response to CD28 costimulation, CD40 signaling, or activation of the germinal center kinase. Here we show that SEK1(-/-) recombination-activating gene (RAG)2(-/-) chimeric mice have a partial block in B cell maturation. However, peripheral B cells displayed normal responses to IL-4, IgM, and CD40 cross-linking. SEK1(-/-) peripheral T cells showed decreased proliferation and IL-2 production after CD28 costimulation and PMA/Ca2+ ionophore activation. Although CD28 expression was absolutely crucial to generate vesicular stomatitis virus (VSV)-specific germinal centers, SEK1(-/-)RAG2(-/-) chimeras mounted a protective antiviral B cell response, exhibited normal IgG class switching, and made germinal centers in response to VSV. Interestingly, PMA/Ca2+ ionophore stimulation, which mimics TCR-CD3 and CD28-mediated signal transduction, induced SAPK/JNK activation in peripheral T cells, but not in thymocytes, from SEK1(-/-) mice. These results show that signaling pathways for SAPK activation are developmentally regulated in T cells. Although SEK1(-/-) thymocytes failed to induce SAPK/JNK in response to PMA/Ca2+ ionophore, SEK1(-/-)RAG2(-/-) thymocytes proliferated and made IL-2 after PMA/Ca2+ ionophore and CD3/CD28 stimulation, albeit at significantly lower levels compared to SEK1(+/+)RAG2(-/-) thymocytes, implying that CD28 costimulation and PMA/Ca2+ ionophore-triggered signaling pathways exist that can mediate proliferation and IL-2 production independently of SAPK activation. Our data provide the first genetic evidence that SEK1 is an important effector molecule that relays CD28 signaling to IL-2 production and T cell proliferation.


Asunto(s)
Antígenos CD28/metabolismo , Interleucina-2/biosíntesis , MAP Quinasa Quinasa 4 , Quinasas de Proteína Quinasa Activadas por Mitógenos , Proteínas Quinasas Activadas por Mitógenos , Proteínas Quinasas/deficiencia , Proteínas Serina-Treonina Quinasas/deficiencia , Proteínas Tirosina Quinasas/deficiencia , Linfocitos T/enzimología , Linfocitos T/inmunología , Animales , Linfocitos B/citología , Linfocitos B/enzimología , Linfocitos B/inmunología , Secuencia de Bases , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Diferenciación Celular , Quimera , Cartilla de ADN/genética , Centro Germinal/citología , Centro Germinal/inmunología , Región de Cambio de la Inmunoglobulina , Proteínas Quinasas JNK Activadas por Mitógenos , Activación de Linfocitos , Ratones , Ratones Noqueados , Reacción en Cadena de la Polimerasa , Proteínas Quinasas/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Tirosina Quinasas/genética , Recombinación Genética , Transducción de Señal , Virus de la Estomatitis Vesicular Indiana/inmunología , Virus de la Estomatitis Vesicular Indiana/patogenicidad
12.
J Exp Med ; 194(6): 757-68, 2001 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-11560992

RESUMEN

The dual specificity kinases mitogen-activated protein kinase (MAPK) kinase (MKK)7 and MKK4 are the only molecules known to directly activate the stress kinases stress-activated protein kinases (SAPKs)/c-Jun N-terminal kinases (JNKs) in response to environmental or mitogenic stimuli. To examine the physiological role of MKK7 in hematopoietic cells, we used a gene targeting strategy to mutate MKK7 in murine T and B cells and non-lymphoid mast cells. Loss of MKK7 in thymocytes and mature B cells results in hyperproliferation in response to growth factor and antigen receptor stimulation and increased thymic cellularity. Mutation of mkk7 in mast cells resulted in hyperproliferation in response to the cytokines interleukin (IL)-3 and stem cell factor (SCF). SAPK/JNK activation was completely abolished in the absence of MKK7, even though expression of MKK4 was strongly upregulated in mkk7(-/-) mast cell lines, and phosphorylation of MKK4 occurred normally in response to multiple stress stimuli. Loss of MKK7 did not affect activation of extracellular signal-regulated kinase (ERK)1/2 or p38 MAPK. mkk7(-/-) mast cells display reduced expression of JunB and the cell cycle inhibitor p16INK4a and upregulation of cyclinD1. Reexpression of p16INK4a in mkk7(-/-) mast cells abrogates the hyperproliferative response. Apoptotic responses to a variety of stimuli were not affected. Thus, MKK7 is an essential and specific regulator of stress-induced SAPK/JNK activation in mast cells and MKK7 negatively regulates growth factor and antigen receptor-driven proliferation in hematopoietic cells. These results indicate that the MKK7-regulated stress signaling pathway can function as negative regulator of cell growth in multiple hematopoietic lineages.


Asunto(s)
Linfocitos B/citología , MAP Quinasa Quinasa 4 , Mastocitos/citología , Quinasas de Proteína Quinasa Activadas por Mitógenos/fisiología , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Receptores de Factores de Crecimiento/metabolismo , Linfocitos T/citología , Animales , Linfocitos B/efectos de los fármacos , Linfocitos B/metabolismo , División Celular , Activación Enzimática , Marcación de Gen , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/fisiología , Interleucina-3/metabolismo , Interleucina-3/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos , MAP Quinasa Quinasa 7 , Mastocitos/efectos de los fármacos , Mastocitos/metabolismo , Ratones , Ratones Noqueados , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Mutagénesis , Factor de Células Madre/metabolismo , Factor de Células Madre/farmacología , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Timo/citología
13.
Science ; 293(5538): 2260-3, 2001 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-11567140

RESUMEN

The molecular adapter Fyb/Slap regulates signaling downstream of the T cell receptor (TCR), but whether it plays a positive or negative role is controversial. We demonstrate that Fyb/Slap-deficient T cells exhibit defective proliferation and cytokine production in response to TCR stimulation. Fyb/Slap is also required in vivo for T cell-dependent immune responses. Functionally, Fyb/Slap has no apparent role in the activation of known TCR signaling pathways, F-actin polymerization, or TCR clustering. Rather, Fyb/Slap regulates TCR-induced integrin clustering and adhesion. Thus, Fyb/Slap is the first molecular adapter to be identified that couples TCR stimulation to the avidity modulation of integrins governing T cell adhesion.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteínas Portadoras/fisiología , Integrinas/metabolismo , Activación de Linfocitos , Fosfoproteínas/fisiología , Linfocitos T/fisiología , Actinas/metabolismo , Animales , Antígenos CD/metabolismo , Antígenos de Diferenciación de Linfocitos T/metabolismo , Linfocitos B/inmunología , Complejo CD3/metabolismo , Proteínas Portadoras/genética , Adhesión Celular , Moléculas de Adhesión Celular/metabolismo , Quimera , Marcación de Gen , Humanos , Inmunización , Inmunoglobulina G/biosíntesis , Molécula 1 de Adhesión Intercelular/metabolismo , Interferón gamma/biosíntesis , Interleucina-2/biosíntesis , Interleucina-2/farmacología , Lectinas Tipo C , Antígeno-1 Asociado a Función de Linfocito/metabolismo , Ratones , Fosfoproteínas/genética , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Interleucina-2/metabolismo , Proteínas Recombinantes/metabolismo , Transducción de Señal , Linfocitos T/inmunología , Linfocitos T/metabolismo
14.
Science ; 287(5455): 1040-6, 2000 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-10669416

RESUMEN

Phosphoinositide 3-kinases (PI3Ks) regulate fundamental cellular responses such as proliferation, apoptosis, cell motility, and adhesion. Viable gene-targeted mice lacking the p110 catalytic subunit of PI3Kgamma were generated. We show that PI3Kgamma controls thymocyte survival and activation of mature T cells but has no role in the development or function of B cells. PI3Kgamma-deficient neutrophils exhibited severe defects in migration and respiratory burst in response to heterotrimeric GTP-binding protein (G protein)-coupled receptor (GPCR) agonists and chemotactic agents. PI3Kgamma links GPCR stimulation to the formation of phosphatidylinositol 3,4,5-triphosphate and the activation of protein kinase B, ribosomal protein S6 kinase, and extracellular signal-regulated kinases 1 and 2. Thus, PI3Kgamma regulates thymocyte development, T cell activation, neutrophil migration, and the oxidative burst.


Asunto(s)
Quimiotaxis de Leucocito/fisiología , Activación de Linfocitos , Neutrófilos/fisiología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas , Linfocitos T/inmunología , Timo/citología , Animales , Antígenos CD/análisis , Apoptosis , Línea Celular , Factores Quimiotácticos/farmacología , Proteínas de Unión al GTP Heterotriméricas/metabolismo , Ganglios Linfáticos/citología , Ratones , Ratones Noqueados , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Peritonitis/inmunología , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Estallido Respiratorio , Transducción de Señal , Bazo/citología , Linfocitos T/citología , Timo/inmunología
15.
Theriogenology ; 71(2): 254-63, 2009 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-18760833

RESUMEN

Both the study and the relationship between sperm design and sperm function have been a target of several researchers. In our study we have evaluated the relationship between the morphometry of sperm head and midpiece as well as the relationship between morphometry of these two spermatic components and sperm motion characteristics in the boar. Analysis of regression (lineal and multiple) and principal components analysis were used for the study of these relationships. Semen samples from five Iberian boars were taken for analysis. Analysis of morphometry was assessed by CASMA system and motility by CASA system. Sperm midpiece showed a significant relationship (positive or negative, depending on the morphometric parameter evaluated) with sperm head. VSL, LIN, STR, BCF and VAP showed a significant relationship with several head and midpiece morphometric parameters. Finally, through the analysis of multiple lineal regression we obtained several statistical models that predict STR, LIN, VCL, ALH, BCF, PC1 and PC2 (the last two variables have been obtained from a principal components analysis) as a function of one, two or three morphometric parameters. Our results suggest a co-evolution of sperm head and midpiece and in addition that sperm motion characteristics of porcine spermatozoa are influenced by morphometry of head and midpiece.


Asunto(s)
Semen/citología , Motilidad Espermática/fisiología , Espermatozoides/citología , Porcinos , Animales , Masculino , Análisis de Componente Principal
16.
Braz J Biol ; 79(4): 603-611, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30540103

RESUMEN

The sweet pepper (Capsicum annuum L.) is one of the most important crops in Brazilian farming. Many insect are related to this crop, compromising the quantity and quality of the fruit, representing a production problem. Vegetable diversification is one of the main elements that can be managed for suppressing undesirable insect populations in organic production, once that supports the presence of natural enemies. The basil Ocimum basilicum L. and the marigold Tagetes erecta L. are attractive and nutritious plants for parasitoids, being important candidates for diversified crops. This study evaluated the parasitoids attracted by the association of basil and marigold to organic sweet pepper crop. The experiment comprised three treatments: a) sweet pepper monoculture; b) sweet pepper and basil intercropping; c) sweet pepper and marigold intercropping. Hymenopteran parasitoids were collected over 14 weeks. 268 individuals from 12 families and 41 taxa were collected. Sweet pepper monoculture, sweet pepper-basil intercropping, and sweet pepper-marigold intercropping hosted 40, 98, and 130 individuals and richness of 24, 24, and 23, respectively. Furthermore, the insects of greater abundance in the basil and marigold were different to those collected in the monoculture. The number of parasitoids increased in the associations of sweet pepper with basil and marigold, providing advantages in the use of vegetable diversification for the organic pepper crops management.


Asunto(s)
Biodiversidad , Capsicum/crecimiento & desarrollo , Ocimum basilicum/crecimiento & desarrollo , Tagetes/crecimiento & desarrollo , Avispas/fisiología , Animales , Brasil , Interacciones Huésped-Parásitos
17.
Int J Androl ; 31(5): 490-8, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17651399

RESUMEN

Computer-assisted sperm morphometry analysis was used to determine the effects of cryopreservation on boar sperm head and midpiece morphometry. Sperm-rich fractions were collected from five mature boars. Three microscope slides were prepared from single extended sperm samples prior freezing and post-thawing. All slides were stained with Hemacolor, and 250 sperm images were obtained from each slide. The sperm head dimensions for length, width, area, perimeter and four shape factors and sperm-midpiece dimensions for area, width, angle and distance were determined in each spermatozoa. The effects of sperm freezing on sperm dimensions within and among boars were determined. A previous discriminant analysis of the results was able to correctly classify a 78.3 and 82% of fresh and frozen-thawed spermatozoa respectively. Sperm heads were significantly smaller in cryopreserved spermatozoa than in the companion extended samples for length, width, area and perimeter. Sperm midpieces were also significantly smaller in cryopreserved spermatozoa for width and area. The highest changes in morphometric dimensions after the freeze-thawing process were found in the midpiece of spermatozoa. The variability of morphometric measurements only was significantly different between fresh and thawed samples for head rugosity and midpiece area. The effects of cryopreservation on morphometric parameters were similar in the boars, which allow us to conclude that cryopreservation process does not have a different effect in each individual boar. In summary, morphometric changes associated with the cryopreservation process on boar spermatozoa do not apparently depends on an effect at individual level.


Asunto(s)
Criopreservación , Espermatozoides/citología , Animales , Masculino , Motilidad Espermática , Porcinos
18.
Sci Rep ; 8(1): 6879, 2018 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-29720623

RESUMEN

This work presents results in the field of advanced substrate solutions in order to achieve high crystalline quality group-III nitrides based heterostructures for high frequency and power devices or for sensor applications. With that objective, Low Temperature Co-fired Ceramics has been used, as a non-crystalline substrate. Structures like these have never been developed before, and for economic reasons will represent a groundbreaking material in these fields of Electronic. In this sense, the report presents the characterization through various techniques of three series of specimens where GaN was deposited on this ceramic composite, using different buffer layers, and a singular metal-organic chemical vapor deposition related technique for low temperature deposition. Other single crystalline ceramic-based templates were also utilized as substrate materials, for comparison purposes.

19.
J Environ Radioact ; 87(1): 52-61, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16375997

RESUMEN

Phosphogypsum is a waste produced by the phosphate fertilizer industry. Although phosphogypsum is mainly calcium sulphate dihydrate, it contains elevated levels of impurities, which originate from the source phosphate rock used in the phosphoric acid production. Among these impurities, radionuclides from 238U and 232Th decay series are of most concern due to their radiotoxicity. Other elements, such as rare earth elements (REE) and Ba are also enriched in the phosphogypsum. The bioavailability of radionuclides (226Ra, 210Pb and 232Th), rare earth elements and Ba to the surrounding aquatic system was evaluated by the application of sequential leaching of the phosphogypsum samples from the Brazilian phosphoric acid producers. The sequential extraction results show that most of the radium and lead are located in the "iron oxide" (non-CaSO4) fraction, and that only 13-18% of these radionuclides are distributed in the most labile fraction. Th, REE and Ba were found predominantly in the residual phase, which corresponds to a small fraction of the phosphate rock or monazite that did not react and to insoluble compounds such as sulphates, phosphates and silicates. It can be concluded that although all these elements are enriched in the phosphogypsum samples they are not associated with CaSO4 itself and therefore do not represent a threat to the surrounding aquatic environment.


Asunto(s)
Sulfato de Calcio/análisis , Residuos Industriales/análisis , Ácidos Fosfóricos/química , Fósforo/análisis , Contaminantes Radiactivos/análisis , Radioisótopos/análisis , Oligoelementos/análisis , Bario/análisis , Brasil , Sulfato de Calcio/química , Fertilizantes , Plomo/análisis , Metales de Tierras Raras/análisis , Fosfatos/análisis , Fósforo/química , Radioisótopos/química , Radio (Elemento)/análisis , Silicatos/análisis , Solubilidad , Oligoelementos/química
20.
Radiat Prot Dosimetry ; 121(2): 179-85, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16531459

RESUMEN

Phosphogypsum, a waste by-product derived from the wet process production of phosphoric acid, represents a serious problem facing the phosphate industry in Brazil. This by-product (mainly calcium sulphate dihydrate) precipitates during the reaction of sulphuric acid with phosphate rock and is stored at a rate of about 4x10(6) kg per day on several piles in Cubatão, Brazil. Contents of natural radionuclides from thorium and uranium series were measured in Brazilian phosphogypsum samples from disposal piles, using high-resolution gamma ray spectrometry and instrumental neutron activation analysis (NAA). These phosphogypsum piles present a potential threat to the surrounding environment and to the individual occupationally exposed. The results obtained in this study show that radionuclides, although present in relatively high concentrations in phosphogypsum, do not imply in significant doses for individuals occupationally exposed. The results obtained for the water activity in the monitor wells showed that the run-off of the piles is influenced by the activity present in the piles, giving indication of a possible groundwater contamination. Sediments from rivers in the area of influence of the pile presented higher concentrations of 238U and 232Th when compared with reference values.


Asunto(s)
Sulfato de Calcio/análisis , Ambiente , Exposición Profesional , Fósforo/análisis , Brasil , Fosfatos/análisis , Radioisótopos/análisis , Espectrometría gamma , Torio/análisis , Uranio/análisis
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