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1.
J Adolesc Health ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38864792

RESUMEN

PURPOSE: Cyberbullying is a crucial issue that affects adolescent mental health, with evidence to suggest that adolescents who are victims of cyberbullying are at higher risk for self-harm. However, longitudinal evidence is lacking, meaning the direction of effects cannot be established. This study investigated longitudinal associations between levels of cyberbullying involvement (bully, victim, or both), frequency, and self-harm a year later in an adolescent sample. METHODS: Data were collected from Year 9 students (13-14-year-olds; N = 1,195) enrolled in 19 schools in Southwest England using an online questionnaire with a 1-year follow-up period (October 2019-October 2020). Multivariable logistic regression analysis was conducted to test for associations between different levels of cyberbullying involvement at baseline and the likelihood of self-harm a year later, adjusting for key covariates. A secondary regression analysis also explored the associations between the frequency of cyberbullying involvement at baseline and subsequent self-harm. RESULTS: Compared to those with no cyberbullying involvement, individuals who were both victims and perpetrators (adjusted odds ratio = 2.94, 95% confidence interval: 1.99-4.34) as well as victims only (adjusted odds ratio = 2.81, 95% confidence interval: 1.95-4.04) showed an increased risk of subsequent self-harm. In terms of frequency, associations were found between frequent and occasional cyberbullying and self-harm for both victims and perpetrators; however, associations for the perpetrator group attenuated to the null following adjustment for covariates. DISCUSSION: Our findings highlight cyberbullying in early adolescence as a risk factor for subsequent self-harm. Cyberbullying prevention should be a priority for school mental health interventions, with consideration that most perpetrators of cyberbullying may also be victims.

2.
Bull Natl Res Cent ; 46(1): 194, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35818410

RESUMEN

Background: On the staggering emergence of the Omicron variant, numerous questions arose about the evolution of virulence and transmissibility in microbes. Main body of the abstract: The trade-off hypothesis has long speculated the exchange of virulence for the sake of superior transmissibility in a wide array of pathogens. While this certainly applies to the case of the Omicron variant, along with influenza virus, various reports have been allocated for an array of pathogens such as human immunodeficiency virus (HIV), malaria, hepatitis B virus (HBV) and tuberculosis (TB). The latter abide to another form of trade-off, the invasion-persistence trade-off. In this study, we aim to explore the molecular mechanisms and mutations of different obligate intracellular pathogens that attenuated their more morbid characters, virulence in acute infections and invasion in chronic infections. Short conclusion: Recognizing the mutations that attenuate the most morbid characters of pathogens such as virulence or persistence can help in tailoring new therapies for such pathogens. Targeting macrophage tropism of HIV by carbohydrate-binding agents, or targeting the TMPRSS2 receptors to prevent pulmonary infiltrates of COVID-19 is an example of how important is to recognize such genetic mechanisms.

3.
Mol Pharmacol ; 97(4): 295-303, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32102968

RESUMEN

The main objective of this study was to clarify the topical mechanisms underlying diclofenac-induced gastric toxicity by considering for the first time both ionization states of this nonsteroidal anti-inflammatory drug. 1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) liposomes were the model system chosen to mimic the protective phospholipid layers of the gastric mucosa and to describe the interactions with diclofenac, considering the pH gradient found in the gastric mucosa (3 < pH < 7.4). Complementary experimental techniques were combined to evaluate the drug's affinity for DMPC bilayers, as well as to assess the drug's effects on the structural properties of the phospholipid bilayer. The diclofenac-DMPC interactions were clearly dependent on the drug's ionization state. Neutral diclofenac displayed greater affinity for DMPC bilayers than anionic diclofenac. Moreover, the protonated/neutral form of the drug induced more pronounced and/or distinct alterations in the structure of the DMPC bilayer than the deprotonated/ionized form, considering similar membrane concentrations. Therefore, neutral diclofenac-induced changes in the structural properties of the external phospholipid layers of the gastric mucosa may constitute an additional toxicity mechanism of this worldwide-used drug, which shall be considered for the development of safer therapeutic strategies. SIGNIFICANCE STATEMENT: Neutral or anionic diclofenac exerted distinct alterations in phosphatidylcholine bilayers, which are used in this work as models for the protective phospholipid layers of the gastric mucosa. Remarkable changes were induced by neutral diclofenac in the structural properties of the phospholipid bilayer, suggesting that both ionized and neutral states of nonsteroidal anti-inflammatory drugs must be considered to clarify their mechanisms of toxicity and to ultimately develop safer anti-inflammatory drugs.


Asunto(s)
Antiinflamatorios no Esteroideos/toxicidad , Diclofenaco/toxicidad , Dimiristoilfosfatidilcolina/química , Mucosa Gástrica/efectos de los fármacos , Membrana Dobles de Lípidos/química , Mucosa Gástrica/química , Concentración de Iones de Hidrógeno , Liposomas/química , Estructura Molecular , Dispersión del Ángulo Pequeño , Difracción de Rayos X
4.
J Appl Toxicol ; 38(8): 1081-1090, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29532501

RESUMEN

Tributyltin (TBT) is found in human blood and other tissues and thus is of considerable concern as to its effects on human health. Previous studies have demonstrated that TBT has detrimental effects on immune function. Recently, we found that exposures to TBT caused increased secretion of two important proinflammatory cytokines, tumor necrosis factor alpha (TNFα) and interferon gamma (IFNγ). Elevation of either of these cytokines has the potential to cause chronic inflammation, which is an important factor in a number of diseases including cancer. The current study examined the mechanism of TBT-induced elevations of TNFα and IFNγ secretion and found that the p38 mitogen-activated protein kinase pathway was essential to the ability of TBT to stimulate secretion. Additionally, this study demonstrated that increased secretion of these cytokines was due to TBT-induced increases in their overall synthesis, rather than simply being due to an increase in the release of already formed proteins. The TBT-induced increases in synthesis were evident within 6 hours of exposure. The p38 mitogen-activated protein kinase pathway is also necessary for the TBT-induced increases in both TNFα and IFNγ synthesis. The role of increased transcription of TNFα and IFNγ mRNA in response to TBT exposures as a possible explanation for the increased synthesis of these cytokines was also examined. It was found that increased mRNA levels did not appear to explain fully the increases in either TNFα or IFNγ synthesis. Thus, TBT is able to increase secretion of two important proinflammatory cytokines by increasing their synthesis.


Asunto(s)
Contaminantes Ambientales/toxicidad , Interferón gamma/biosíntesis , Leucocitos Mononucleares/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Compuestos de Trialquiltina/toxicidad , Factor de Necrosis Tumoral alfa/biosíntesis , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Interferón gamma/metabolismo , Leucocitos Mononucleares/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
5.
Med Res Rev ; 37(4): 802-859, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28005273

RESUMEN

The efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) against inflammation, pain, and fever has been supporting their worldwide use in the treatment of painful conditions and chronic inflammatory diseases until today. However, the long-term therapy with NSAIDs was soon associated with high incidences of adverse events in the gastrointestinal tract. Therefore, the search for novel drugs with improved safety has begun with COX-2 selective inhibitors (coxibs) being straightaway developed and commercialized. Nevertheless, the excitement has fast turned to disappointment when diverse coxibs were withdrawn from the market due to cardiovascular toxicity. Such events have once again triggered the emergence of different strategies to overcome NSAIDs toxicity. Here, an integrative review is provided to address the breakthroughs of two main approaches: (i) the association of NSAIDs with protective mediators and (ii) the design of novel compounds to target downstream and/or multiple enzymes of the arachidonic acid cascade. To date, just one phosphatidylcholine-associated NSAID has already been approved for commercialization. Nevertheless, the preclinical and clinical data obtained so far indicate that both strategies may improve the safety of nonsteroidal anti-inflammatory therapy.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/uso terapéutico , Animales , Humanos , Relación Estructura-Actividad
6.
N Engl J Med ; 361(18): 1727-35, 2009 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-19864672

RESUMEN

BACKGROUND: Chronic mucocutaneous candidiasis may be manifested as a primary immunodeficiency characterized by persistent or recurrent infections of the mucosa or the skin with candida species. Most cases are sporadic, but both autosomal dominant inheritance and autosomal recessive inheritance have been described. METHODS: We performed genetic studies in 36 members of a large, consanguineous five-generation family, in which 4 members had recurrent fungal infections and an additional 3 members died during adolescence, 2 after invasive infection of the brain with candida species. All 36 family members were enrolled in the study, and 22 had blood samples taken for DNA analysis. Homozygosity mapping was used to locate the mutated gene. In the 4 affected family members (patients) and the 18 unaffected members we sequenced CARD9, the gene encoding the caspase recruitment domain-containing protein 9, carried out T-cell phenotyping, and performed functional studies, with the use of either leukocytes from the patients or a reconstituted murine model of the genetic defect. RESULTS: We found linkage (lod score, 3.6) to a genomic interval on chromosome 9q, including CARD9. All four patients had a homozygous point mutation in CARD9, resulting in a premature termination codon (Q295X). Healthy family members had wild-type expression of the CARD9 protein; the four patients lacked wild-type expression, which was associated with low numbers of Th17 cells (helper T cells producing interleukin-17). Functional studies based on genetic reconstitution of myeloid cells from Card9(-/-) mice showed that the Q295X mutation impairs innate signaling from the antifungal pattern-recognition receptor dectin-1. CONCLUSIONS: An autosomal recessive form of susceptibility to chronic mucocutaneous candidiasis is associated with homozygous mutations in CARD9.


Asunto(s)
Proteínas Adaptadoras de Señalización CARD/genética , Candidiasis Mucocutánea Crónica/genética , Codón sin Sentido , Predisposición Genética a la Enfermedad , Adolescente , Animales , Proteínas Adaptadoras de Señalización CARD/metabolismo , Candida , Candidiasis/genética , Candidiasis/inmunología , Consanguinidad , Análisis Mutacional de ADN , Femenino , Genes Recesivos , Homocigoto , Humanos , Escala de Lod , Masculino , Meningitis Fúngica/genética , Ratones , Ratones Noqueados , Persona de Mediana Edad , Linaje , ARN Mensajero/metabolismo , Transducción de Señal/genética , Linfocitos T , Adulto Joven
7.
J Invest Dermatol ; 127(12): 2799-806, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17597818

RESUMEN

This study examined the suitability of microdialysis to assess the time course of cytokine generation from discrete sites within the skin following intradermal injection of allergen. Cytokines were recovered using two microdialysis probes, one close to the point of allergen injection and the other 1 cm away but within the area of the late-phase induration. Skin biopsies taken at both sites were stained immunocytochemically to investigate possible relationships between cytokine generation, expression of adhesion molecules, and recruitment of neutrophils and eosinophils during the late-phase allergic response. The cytokine response to probe insertion was assessed using a single probe in the opposite arm (control). At baseline, microdialysate contained low levels of IL-1alpha, IL-5, IL-8, IL-12, GM-CSF, and TNFalpha (n=27-33). At control sites, this was followed by increases in IL-6 and IL-8 at 3 and 6 hours. Allergen increased TNFalpha levels in 3/11 individuals within 30 minutes at the injection site. Levels of IL-6 and IL-8 rose rapidly and were significantly greater (P<0.05) than that of controls at 3 and 6 hours at both injection and distant sites. Adhesion molecule expression and leukocyte infiltration were elevated only at the allergen injection site, suggesting a complex relationship between cytokine generation and cellular events in allergic inflammation. In conclusion, microdialysis can be used to distinguish temporal and spatial changes in protein profiles in the skin. Furthermore, when used in conjunction with skin biopsies, it provides novel information about the mechanisms of dermal inflammation.


Asunto(s)
Alérgenos/metabolismo , Citocinas/metabolismo , Microdiálisis/métodos , Piel/metabolismo , Adhesión Celular , Edema/patología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Humanos , Inflamación , Interleucina-12/metabolismo , Interleucina-1alfa/metabolismo , Interleucina-5/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Piel/patología , Fenómenos Fisiológicos de la Piel , Factores de Tiempo , Factor de Necrosis Tumoral alfa/metabolismo
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