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1.
Biol Sex Differ ; 15(1): 48, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867310

RESUMO

INTRODUCTION: Sexual dimorphism significantly influences cancer incidence and prognosis. Notably, females exhibit a lower risk and favorable prognosis for non-reproductive cancers compared to males, a pattern observable beyond the scope of risk behaviors such as alcohol consumption and smoking. Colorectal cancer, ranking third in global prevalence and second in mortality, disproportionately affects men. Sex steroid hormones, particularly estrogens and androgens, play crucial roles in cancer progression, considering epidemiological in vivo and in vitro, in general estrogens imparting a protective effect in females and androgens correlating with an increasing risk of colorectal cancer development. MAIN BODY: The hormonal impact on immune response is mediated by receptor interactions, resulting in heightened inflammation, modulation of NF-kB, and fostering an environment conducive to cancer progression and metastasis. These molecules also influence the enteric nervous system, that is a pivotal in neuromodulator release and intestinal neuron stimulation, also contributes to cancer development, as evidenced by nerve infiltration into tumors. Microbiota diversity further intersects with immune, hormonal, and neural mechanisms, influencing colorectal cancer dynamics. A comprehensive understanding of hormonal influences on colorectal cancer progression, coupled with the complex interplay between immune responses, microbiota diversity and neurotransmitter imbalances, underpins the development of more targeted and effective therapies. CONCLUSIONS: Estrogens mitigate colorectal cancer risk by modulating anti-tumor immune responses, enhancing microbial diversity, and curbing the pro-tumor actions of the sympathetic and enteric nervous systems. Conversely, androgens escalate tumor growth by dampening anti-tumor immune activity, reducing microbial diversity, and facilitating the release of tumor-promoting factors by the nervous system. These findings hold significant potential for the strategic purposing of drugs to fine-tune the extensive impacts of sex hormones within the tumor microenvironment, promising advancements in colorectal cancer therapies.


Assuntos
Neoplasias Colorretais , Caracteres Sexuais , Humanos , Neoplasias Colorretais/metabolismo , Animais , Feminino , Hormônios Esteroides Gonadais/metabolismo , Hormônios Esteroides Gonadais/fisiologia , Masculino
2.
Front Immunol ; 15: 1332933, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38576624

RESUMO

Introduction: Worldwide, breast cancer is the most important cancer in incidence and prevalence in women. Different risk factors interact to increase the probability of developing it. Biological agents such as helminth parasites, particularly their excretory/secretory antigens, may play a significant role in tumor development. Helminths and their antigens have been recognized as inducers or promoters of cancer due to their ability to regulate the host's immune response. Previously in our laboratory, we demonstrated that chronic infection by Toxocara canis increases the size of mammary tumors, affecting the systemic response to the parasite. However, the parasite does not invade the tumor, and we decided to study if the excretion/secretion of antigens from Toxocara canis (EST) can affect the progression of mammary tumors or the pathophysiology of cancer which is metastasis. Thus, this study aimed to determine whether excretion/secretion T. canis antigens, injected directly into the tumor, affect tumor growth and metastasis. Methods: We evaluated these parameters through the monitoring of the intra-tumoral immune response. Results: Mice injected intratumorally with EST did not show changes in the size and weight of the tumors; although the tumors showed an increased microvasculature, they did develop increased micro and macro-metastasis in the lung. The analysis of the immune tumor microenvironment revealed that EST antigens did not modulate the proportion of immune cells in the tumor, spleen, or peripheral lymph nodes. Macroscopic and microscopic analyses of the lungs showed increased metastasis in the EST-treated animals compared to controls, accompanied by an increase in VEGF systemic levels. Discussion: Thus, these findings showed that intra-tumoral injection of T. canis EST antigens promote lung metastasis through modulation of the tumor immune microenvironment.


Assuntos
Neoplasias da Mama , Parasitos , Toxocara canis , Toxocaríase , Humanos , Feminino , Animais , Camundongos , Antígenos de Helmintos , Injeções Intralesionais , Pulmão , Microambiente Tumoral
3.
Front Biosci (Landmark Ed) ; 29(3): 124, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38538283

RESUMO

BACKGROUND: Toxocara canis (T. canis) is a helminth parasite of zoonotic and veterinary health significance that causes the disease known as Toxocariasis. This disease has been associated with conditions of poverty, especially in tropical climate zones throughout the world. Although it rarely causes important clinical manifestations, T. canis can lead to blindness, meningoencephalitis, or other nervous manifestations in humans. Moreover, some studies show its importance in the development of tumor growth, which have been associated with the parasite's ability to modulate the host's immune response. While different studies have evaluated the immune response during this disease, currently, there are no studies where the infection is analyzed from the perspective of sexual dimorphism. METHODS: To evaluate sex differences in susceptibility, we analyzed lesions and parasite loads in lung and liver at 7 days post-infection. In addition, immune cell subpopulations were analyzed in spleen, mesenteric and peripheral lymph nodes. Finally, the production of cytokines and specific antibodies were determined in the serum. Statical analyses were performed using a Two-way ANOVA and a post-hoc Bonferroni multiple comparison test. RESULTS: Female rats had a higher number of larvae in the liver, while male rats had them in the lungs. The percentages of immune cells were evaluated, and in most cases, no significant differences were observed. Regarding the cytokines production, infection can generate a decrease in Th1 such as IL-1ß in both sexes and IL-6 only in females. In the case of Th2, IL-4 increases only in infected males and IL-5 increases in males while decreasing in females due to the effect of infection. IL-10 also decreases in both sexes as a consequence of the infection, and TGF-ß only in females. Finally, the infection generates the production of antibodies against the parasite, however, their quantity is lower in females. CONCLUSIONS: This study demonstrates that T. canis infection is dimorphic and affects females more than males. This is due to a polarization of the inadequate immune response, which is reflected as a higher parasite load in this sex.


Assuntos
Toxocara canis , Toxocaríase , Humanos , Feminino , Ratos , Masculino , Animais , Toxocaríase/parasitologia , Toxocaríase/patologia , Toxocara canis/fisiologia , Caracteres Sexuais , Citocinas , Imunidade
4.
J Interferon Cytokine Res ; 44(1): 26-36, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37962860

RESUMO

Although the modulation of immunity by exercise has been a long-studied paradigm, the molecular pathways connecting the two are still not fully understood. Regular moderate aerobic exercise is associated with improved health and directly impacts the immune system by changing the proportion of cell subpopulations, their function, and interleukin production. The endocannabinoid system has gained importance as an immune modulator, affected by moderate aerobic promoting the production of endocannabinoids, which are ligands of the cannabinoid receptors (CBRs) expressed on the surface of all immune cells. Our group previously reported a reduction of lymphocytic populations in the spleen of chronically exercised rats, accompanied by an increase in CBR expression. Given the complex and compartmentalized nature of the immune system, we decided to study the effects of chronic exercise on the proportion of peripheral blood mononuclear cells, serum interleukins, and the expression of CBRs on these cells. Overall, our results indicate that chronic exercise decreases the proportion of T helper and Tγδ cells but increases the expression of cannabinoids (CBR1) on T helper and natural killer cells, and the production of interleukins, including IL-1ß, interferon-gamma, tumor necrosis factor-alpha, IL-10, and IL-4, suggesting higher reactivity and efficiency from the immune system conferred by exercise.


Assuntos
Citocinas , Leucócitos Mononucleares , Ratos , Animais , Citocinas/metabolismo , Interleucinas/metabolismo , Células Matadoras Naturais , Fator de Necrose Tumoral alfa/metabolismo
5.
Curr Opin Pediatr ; 35(5): 585-589, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37255048

RESUMO

PURPOSE OF REVIEW: This is an overview of the effects of COVID-19 in the gastrointestinal tract in children, and current evidence of the impact of COVID-19 in pediatric patients with chronic gastrointestinal conditions, including inflammatory bowel disease (IBD), chronic liver disease, and disorders of the gut-brain interaction. RECENT FINDINGS: Children with COVID-19 have a milder course and more favorable outcomes than adults, even in those with immunosuppression due to IBD or liver transplantation. Children with chronic gastrointestinal conditions do not have worse clinical outcomes than healthy children and infection itself has not been linked to an increased incidence of conditions such as IBD and celiac disease, but results regarding post-infectious irritable bowel syndrome are mixed. SUMMARY: Research specific to pediatrics is needed, particularly in post-infectious disorders of the gut-brain interaction (PI-DGBIs) and long COVID-19. Data extrapolated from adult trials may not apply to children, as their clinical course is different. PI-DGBIs and long COVID-19 require special attention, as they represent a major morbidity burden in children.


Assuntos
COVID-19 , Doenças Inflamatórias Intestinais , Síndrome do Intestino Irritável , Criança , Humanos , Síndrome de COVID-19 Pós-Aguda , COVID-19/epidemiologia , Trato Gastrointestinal
6.
Int J Mol Sci ; 23(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35269666

RESUMO

Breast cancer (BC) metastasis represents the main physiopathology leading to poor prognosis and death. Bisphenol A (BPA) is a pollutant, classified as an endocrine-disrupting chemical compound with estrogenic properties, their exposure in the early stages of neonatal life leads to an increase in the size and weight of breast tumors and induces cellular changes in the tumoral immune microenvironment where cytokines play a key role. Thus, we used female BALB/c mice exposed neonatally to a single dose of BPA. Once mice reached sexual maturity, a mammary tumor was induced, injecting 4T1 cells in situ. After 25 days of injection, we evaluated endocrine alterations, cytokine expression, tissue alterations denoted by macro or micro-metastasis in the lung, and cell infiltration induced by metastasis. We found that BPA neonatal treatment did not show significant endocrine alterations. Noteworthy, BPA led to an augmented rate of metastasis to the lung associated with higher intratumoral expression of IL-1ß, IL-6, IFN-γ, TNF-α, and VEGF. Our data suggest that cytokines are key players in the induction of BC metastasis and that BPA (an environmental pollutant) should be considered as a risk factor in the clinical history of patients as a possible inductor of BC metastasis.


Assuntos
Neoplasias da Mama , Disruptores Endócrinos , Neoplasias Pulmonares , Animais , Compostos Benzidrílicos/toxicidade , Citocinas , Disruptores Endócrinos/toxicidade , Feminino , Humanos , Neoplasias Pulmonares/induzido quimicamente , Camundongos , Modelos Teóricos , Fenóis , Microambiente Tumoral
7.
Case Rep Pediatr ; 2021: 5578810, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336339

RESUMO

Crohn's disease is an inflammatory bowel disease that can have multiple extraintestinal manifestations and can develop prior to, following, or simultaneously with gastrointestinal tract involvement (Aberumand et al. (2017), Georgious et al. (2006), Larsen et al. (2010), Levine and Burakoff (2011), Louis et al. (2018)). This report examines the case of a 16-year-old male with a rash of the genital, intergluteal, and inguinal regions refractory to antimicrobial treatments suspicious for an extraintestinal manifestation of Crohn's disease. The patient was diagnosed with inflammatory, nonfistulizing colonic Crohn's disease following presentation with gastrointestinal symptoms including abdominal pain and bloody stools 6 months after the onset of the rash. The genital lesions resolved after starting treatment for Crohn's disease with adalimumab.

8.
Birth Defects Res ; 112(17): 1341-1361, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32767490

RESUMO

BACKGROUND: As a result of human socioeconomic activity, industrial wastes have increased distressingly. Plastic pollution is globally distributed across the world due to its properties of buoyancy and durability. A big health hazard is the sorption of toxicants to plastic while traveling through the environment. Two broad classes of plastic-related chemicals are of critical concern for human health-bisphenols and phthalates. Bisphenol A (BPA) is an endocrine-disruptor compound (EDC) with estrogenic activity. It is used in the production of materials that are used daily. The endocrine modulating activity of BPA and its effects on reproductive health has been widely studied. BPA also has effects on the immune system; however, they are poorly investigated and the available data are inconclusive. Phthalates are also EDCs used as plasticizers in a wide array of daily-use products. Since these compounds are not covalently bound to the plastic matrix, they easily leach out from it, leading to high human exposure. These compounds exert several cell effects through modulating different endocrine pathways, such as estrogen, androgen, peroxisome proliferator-activated receptor gamma, and arylhydrocarbon receptor pathways. The exposure to both classes of plastic derivatives during critical periods has detrimental effects on human health. METHODS: In this review, we have compiled the most important of their perinatal effects on the function of the immune system and their relationship to the development of different types of cancer. RESULTS/CONCLUSION: The administration of bisphenols and phthalates during critical stages of development affects important immune system components, and the immune function; which might be related to the development of different diseases including cancer.


Assuntos
Disruptores Endócrinos , Neoplasias , Criança , Disruptores Endócrinos/toxicidade , Feminino , Humanos , Sistema Imunitário , Microplásticos , Plásticos , Gravidez
9.
Cell ; 177(6): 1405-1418.e17, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31130379

RESUMO

How do genes modify cellular growth to create morphological diversity? We study this problem in two related plants with differently shaped leaves: Arabidopsis thaliana (simple leaf shape) and Cardamine hirsuta (complex shape with leaflets). We use live imaging, modeling, and genetics to deconstruct these organ-level differences into their cell-level constituents: growth amount, direction, and differentiation. We show that leaf shape depends on the interplay of two growth modes: a conserved organ-wide growth mode that reflects differentiation; and a local, directional mode that involves the patterning of growth foci along the leaf edge. Shape diversity results from the distinct effects of two homeobox genes on these growth modes: SHOOTMERISTEMLESS broadens organ-wide growth relative to edge-patterning, enabling leaflet emergence, while REDUCED COMPLEXITY inhibits growth locally around emerging leaflets, accentuating shape differences created by patterning. We demonstrate the predictivity of our findings by reconstructing key features of C. hirsuta leaf morphology in A. thaliana. VIDEO ABSTRACT.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Cardamine/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Arabidopsis/genética , Cardamine/genética , Linhagem da Célula/genética , Biologia Computacional/métodos , Regulação da Expressão Gênica de Plantas/genética , Folhas de Planta/genética , Proteínas de Plantas/metabolismo
11.
Biomed Res Int ; 2018: 4093435, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29789790

RESUMO

CD13 is a membrane glycoprotein with aminopeptidase activity, expressed on several cell types, including myeloid cells (dendritic cells, monocytes, macrophages, neutrophils, etc.). CD13 participates in several functions such as proteolytic regulation of bioactive peptides, viral receptor, angiogenesis, and tumor metastasis. CD13 has also been proposed to participate in cell adhesion, as crosslinking of CD13 by certain CD13-specific antibodies induces homotypic aggregation of monocytes and heterotypic adhesion of monocytes to endothelial cells. We generated two monoclonal antibodies (mAbs C and E) that block homotypic aggregation of U-937 monocytic cells induced by CD13-specific mAb 452. Moreover, the mAbs cause detachment of cells whose aggregation was induced by CD13 crosslinking. Both mAbs also inhibit heterotypic adhesion of U-937 monocytes to endothelial cells. mAbs C and E recognize membrane CD13 but bind to epitopes different from that recognized by mAb 452. Crosslinking of CD13 by mAb C or E is required to inhibit adhesion, as monovalent Fab fragments are not sufficient. Thus, C and E antibodies recognize a distinct epitope on CD13, and binding to this epitope interferes with both CD13-mediated cell adhesion and enzymatic activity. These antibodies may represent important tools to study cell-cell interactions mediated by CD13 in physiological and pathological conditions.


Assuntos
Antígenos CD13/metabolismo , Epitopos/metabolismo , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/farmacologia , Adesão Celular , Humanos , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/farmacologia , Camundongos , Células THP-1 , Células U937
12.
Sci Rep ; 6: 32552, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27586352

RESUMO

Oligomerization of allergens plays an important role in IgE-mediated reactions, as effective crosslinking of IgE- FcεRI complexes on the cell membrane is dependent on the number of exposed B-cell epitopes in a single allergen molecule or on the occurrence of identical epitopes in a symmetrical arrangement. Few studies have attempted to experimentally demonstrate the connection between allergen dimerization and the ability to trigger allergic reactions. Here we studied plant allergenic profilins rHev b 8 (rubber tree) and rZea m 12 (maize) because they represent an important example of cross-reactivity in the latex-pollen-food syndrome. Both allergens in their monomeric and dimeric states were isolated and characterized by exclusion chromatography and mass spectrometry and were used in immunological in vitro experiments. Their crystal structures were solved, and for Hev b 8 a disulfide-linked homodimer was found. Comparing the structures we established that the longest loop is relevant for recognition by IgE antibodies, whereas the conserved regions are important for cross-reactivity. We produced a novel monoclonal murine IgE (mAb 2F5), specific for rHev b 8, which was useful to provide evidence that profilin dimerization considerably increases the IgE-mediated degranulation in rat basophilic leukemia cells.


Assuntos
Alérgenos/química , Hevea/metabolismo , Imunoglobulina E/imunologia , Proteínas de Plantas/química , Multimerização Proteica , Zea mays/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/metabolismo , Degranulação Celular , Cristalografia por Raios X , Feminino , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/imunologia , Imunização , Imunoglobulina G/metabolismo , Interferometria , Camundongos Endogâmicos BALB C , Modelos Moleculares , Profilinas/química , Ratos
14.
Genes Dev ; 29(22): 2391-404, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26588991

RESUMO

Two interrelated problems in biology are understanding the regulatory logic and predictability of morphological evolution. Here, we studied these problems by comparing Arabidopsis thaliana, which has simple leaves, and its relative, Cardamine hirsuta, which has dissected leaves comprising leaflets. By transferring genes between the two species, we provide evidence for an inverse relationship between the pleiotropy of SHOOTMERISTEMLESS (STM) and BREVIPEDICELLUS (BP) homeobox genes and their ability to modify leaf form. We further show that cis-regulatory divergence of BP results in two alternative configurations of the genetic networks controlling leaf development. In C. hirsuta, ChBP is repressed by the microRNA164A (MIR164A)/ChCUP-SHAPED COTYLEDON (ChCUC) module and ChASYMMETRIC LEAVES1 (ChAS1), thus creating cross-talk between MIR164A/CUC and AS1 that does not occur in A. thaliana. These different genetic architectures lead to divergent interactions of network components and growth regulation in each species. We suggest that certain regulatory genes with low pleiotropy are predisposed to readily integrate into or disengage from conserved genetic networks influencing organ geometry, thus rapidly altering their properties and contributing to morphological divergence.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Cardamine/crescimento & desenvolvimento , Cardamine/genética , Redes Reguladoras de Genes/genética , Proteínas de Homeodomínio/genética , Folhas de Planta , Proteínas de Plantas/genética , Arabidopsis/anatomia & histologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cardamine/anatomia & histologia , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo
15.
Front Genet ; 6: 172, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26042145

RESUMO

FAST (FAST Analysis of Sequences Toolbox) provides simple, powerful open source command-line tools to filter, transform, annotate and analyze biological sequence data. Modeled after the GNU (GNU's Not Unix) Textutils such as grep, cut, and tr, FAST tools such as fasgrep, fascut, and fastr make it easy to rapidly prototype expressive bioinformatic workflows in a compact and generic command vocabulary. Compact combinatorial encoding of data workflows with FAST commands can simplify the documentation and reproducibility of bioinformatic protocols, supporting better transparency in biological data science. Interface self-consistency and conformity with conventions of GNU, Matlab, Perl, BioPerl, R, and GenBank help make FAST easy and rewarding to learn. FAST automates numerical, taxonomic, and text-based sorting, selection and transformation of sequence records and alignment sites based on content, index ranges, descriptive tags, annotated features, and in-line calculated analytics, including composition and codon usage. Automated content- and feature-based extraction of sites and support for molecular population genetic statistics make FAST useful for molecular evolutionary analysis. FAST is portable, easy to install and secure thanks to the relative maturity of its Perl and BioPerl foundations, with stable releases posted to CPAN. Development as well as a publicly accessible Cookbook and Wiki are available on the FAST GitHub repository at https://github.com/tlawrence3/FAST. The default data exchange format in FAST is Multi-FastA (specifically, a restriction of BioPerl FastA format). Sanger and Illumina 1.8+ FastQ formatted files are also supported. FAST makes it easier for non-programmer biologists to interactively investigate and control biological data at the speed of thought.

16.
J Leukoc Biol ; 98(1): 85-98, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25934926

RESUMO

CD13 is a membrane-bound ectopeptidase, highly expressed on monocytes, macrophages, and dendritic cells. CD13 is involved in diverse functions, including degradation of peptide mediators, cellular adhesion, migration, viral endocytosis, signaling, and positive modulation of phagocytosis mediated by FcγRs and other phagocytic receptors. In this work, we explored whether besides acting as an accessory receptor, CD13 by itself is a primary phagocytic receptor. We found that hCD13 mediates efficient phagocytosis of large particles (erythrocytes) modified so as to interact with the cell only through CD13 in human macrophages and THP-1 monocytic cells. The extent of this phagocytosis is comparable with the phagocytosis mediated through the canonical phagocytic receptor FcγRI. Furthermore, we demonstrated that hCD13 expression in the nonphagocytic cell line HEK293 is sufficient to enable these cells to internalize particles bound through hCD13. CD13-mediated phagocytosis is independent of other phagocytic receptors, as it occurs in the absence of FcγRs, CR3, and most phagocytic receptors. Phagocytosis through CD13 is independent of its enzymatic activity but is dependent on actin rearrangement and activation of PI3K and is partially dependent on Syk activation. Moreover, the cross-linking of CD13 with antibodies rapidly induced pSyk in human macrophages. Finally, we observed that antibody-mediated cross-linking of hCD13, expressed in the murine macrophage-like J774 cell line, induces production of ROS. These results demonstrate that CD13 is a fully competent phagocytic receptor capable of mediating internalization of large particles.


Assuntos
Antígenos CD13/fisiologia , Monócitos/imunologia , Fagocitose/fisiologia , Citoesqueleto de Actina/metabolismo , Animais , Células HEK293 , Humanos , Camundongos , Monócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
17.
Soc Sci Med ; 133: 102-10, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25863725

RESUMO

We conducted qualitative interviews among primary health care teams and community agencies in eight communities in Victoria, Australia which had (1) agreed to be part of a universal primary care and community development intervention to reduce post natal depression and promote maternal health; and (2) were randomised to the comparison arm. The purpose was to document their experience with and interpretation of the trial. Although 'control' in a controlled trial refers to the control of confounding of the trial result by factors other than allocation to the intervention, participants interpreted 'control' to mean restrictions on what they were allowed to do during the trial period. They had agreed not to use the Edinburgh Post Natal Depression Scale or the SF 36 in clinical practice and not to implement any of the elements of the intervention. We found that no elements of the intervention were implemented. However, the extension of the trial from three to five years made the trial agreement a strain. The imposition of trial conditions also encouraged a degree of lateral thinking and innovation in service delivery (quality improvement). This may have potentially contributed to the null trial results. The observations invite interrogation of intervention theory and consequent rethinking of the way contamination in a cluster trial is defined.


Assuntos
Atitude do Pessoal de Saúde , Depressão Pós-Parto/terapia , Atenção Primária à Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Austrália , Feminino , Humanos , Saúde Materna , Equipe de Assistência ao Paciente , Atenção Primária à Saúde/métodos , Pesquisa Qualitativa , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Projetos de Pesquisa , Características de Residência
18.
Plant J ; 73(4): 533-45, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23145478

RESUMO

Leaves show considerable variation in shape, and may be described as simple, when the leaf is entire, or dissected, when the leaf is divided into individual leaflets. Here, we report that the SIMPLE LEAF3 (SIL3) gene is a novel determinant of leaf shape in Cardamine hirsuta - a dissected-leaved relative of the simple-leaved model species Arabidopsis thaliana. We show that SIL3 is required for leaf growth and leaflet formation but leaf initiation is less sensitive to perturbation of SIL3 activity. SIL3 is further required for KNOX (knotted1-like homeobox) gene expression and localized auxin activity maxima, both of which are known to promote leaflet formation. We cloned SIL3 and showed that it encodes RLI2 (RNase L inhibitor 2), an ATP binding cassette-type ATPase with important roles in ribosome recycling and translation termination that are conserved in eukaryotes and archaea. RLI mutants have not been described in plants to date, and this paper highlights the potential of genetic studies in C. hirsuta to uncover novel gene functions. Our data indicate that leaflet development is sensitive to perturbation of RLI2-dependent aspects of cellular growth, and link ribosome function with dissected-leaf development.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Cardamine/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/crescimento & desenvolvimento , Ribossomos/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Cardamine/anatomia & histologia , Cardamine/genética , Proliferação de Células , Clonagem Molecular , Genes de Plantas , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Homeostase , Ácidos Indolacéticos/metabolismo , Microscopia Eletrônica de Varredura , Mutagênese , Terminação Traducional da Cadeia Peptídica , Fenótipo , Folhas de Planta/ultraestrutura , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ribossomos/genética
19.
Cytokine ; 57(1): 158-68, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22137120

RESUMO

IFNγ is a potent activator and IL-10 a powerful inhibitor of macrophage functions. However, neither all cellular functions are enhanced by IFNγ nor IL-10 inhibits all cellular responses. Thus, FcγRs-mediated phagocytosis in monocyte-derived macrophages (MDM) increases after IL-10 treatment, and decreases after treatment with IFNγ, although both IL-10 and IFNγ up regulate FcγRI expression. In this work we investigated the effect of IFNγ and IL-10 on phagocytic signaling by FcγRs in MDM. Treatment with IFNγ diminished phagocytosis of IgG-opsonized SRBC (IgG-SRBC) while treatment with IL-10 increased it. These opposite effects cannot be attributed to changes in FcγR expression induced by each cytokine. Early biochemical responses mediated by FcγRs were distinctly affected by cytokine treatment. Syk phosphorylation and the rise in [Ca(2+)](i) were higher after IL-10 treatment, whereas IFNγ treatment also increased Syk phosphorylation but had no effect on the rise in [Ca(2+)](i). IFNγ treatment led to increased basal levels of F-actin and this effect correlated with the decrease in phagocytosis of both IgG-SRBC and non-opsonized Escherichia coli. IL-10 did not alter F-actin basal levels, and enhanced the phagocytosis of E. coli and IgG-SRBC. The level of F-actin reached after IFNγ treatment was not further increased after stimulation with IgG-SRBC or CCL5, whereas MDM treated with IL-10 showed a slightly higher response than control cells to CCL5. IFNγ increased Rac1-GTP levels. Inhibition of PI3K with LY294002 prevented IFNγ-mediated actin polymerization. Our data suggest that IFNγ induces a higher basal level of F-actin and activation of Rac1, affecting the response to stimuli that induce cytoskeleton rearrangement such as phagocytic or chemotactic stimuli.


Assuntos
Actinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Interferon gama/farmacologia , Monócitos/citologia , Fagocitose/efeitos dos fármacos , Polimerização/efeitos dos fármacos , Proteínas rac1 de Ligação ao GTP/metabolismo , Animais , Sinalização do Cálcio/efeitos dos fármacos , Quimiocina CCL5/metabolismo , Reagentes de Ligações Cruzadas/metabolismo , Ativação Enzimática/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Escherichia coli/citologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Humanos , Imunoglobulina G/metabolismo , Interleucina-10/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Monócitos/efeitos dos fármacos , Proteínas Opsonizantes/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação/efeitos dos fármacos , Proteínas Tirosina Quinases/metabolismo , Receptores de IgG/metabolismo , Ovinos , Quinase Syk , Proteína cdc42 de Ligação ao GTP/metabolismo
20.
J Plant Res ; 123(1): 25-33, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19821009

RESUMO

Cardamine hirsuta, a small crucifer closely related to the model organism Arabidopsis thaliana, offers high genetic tractability and has emerged as a powerful system for studying the genetic basis for diversification of plant form. Contrary to A. thaliana, which has simple leaves, C. hirsuta produces dissected leaves divided into individual units called leaflets. Leaflet formation requires activity of Class I KNOTTED1-like homeodomain (KNOX) proteins, which also promote function of the shoot apical meristem (SAM). In C. hirsuta, KNOX genes are expressed in the leaves whereas in A. thaliana their expression is confined to the SAM, and differences in expression arise through cis-regulatory divergence of KNOX regulation. KNOX activity in C. hirsuta leaves delays the transition from proliferative growth to differentiation thus facilitating the generation of lateral growth axes that give rise to leaflets. These axes reflect the sequential generation of cell division foci across the leaf proximodistal axis in response to auxin activity maxima, which are generated by the PINFORMED1 (PIN1) auxin efflux carriers in a process that resembles organogenesis at the SAM. Delimitation of C. hirsuta leaflets also requires the activity of CUP SHAPED COTYLEDON (CUC) genes, which direct formation of organ boundaries at the SAM. These observations show how species-specific deployment of fundamental shoot development networks may have sculpted simple versus dissected leaf forms. These studies also illustrate how extending developmental genetic studies to morphologically divergent relatives of model organisms can greatly help elucidate the mechanisms underlying the evolution of form.


Assuntos
Cardamine/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Cardamine/anatomia & histologia , Genes Homeobox/fisiologia , Genes de Plantas , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/fisiologia , Elementos Isolantes/fisiologia , Meristema/anatomia & histologia , Meristema/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/fisiologia , Folhas de Planta/anatomia & histologia
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