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1.
PLoS One ; 16(12): e0259494, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34874943

RESUMO

Nuanced public responses to droughts and other chronic environmental crises reflect today's increasingly complex communication ecosystem. At once global and infinitely customizable, this vast array of media and information channels requires existing theory to address the implications of interactions among social media, "traditional" mass media outlets, and information-seeking tools such as search engines. How do these channels intervene in public conversation? What might the agenda-setting perspective have to say? Data collected during peak years of the California drought, 2013-2015, indicate that California residents responded to worsening drought conditions Twitter first, which was the only media behavior directly stimulated by environmental stressors. Google searches stimulated newspaper coverage and Twitter activity, revealing the centrality of search behaviors in this environmental crisis. The findings suggest significant changes to the communication landscape as individual and collective users become increasingly dependent on non-mainstream media channels for information in chronic crisis situations.


Assuntos
Secas , California , Humanos , Comportamento de Busca de Informação , Jornais como Assunto , Saúde Pública , Ferramenta de Busca , Mídias Sociais
2.
PLoS One ; 11(12): e0168102, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27977732

RESUMO

Ureaplasma parvum (U. parvum) is gaining recognition as an important pathogen for chorioamnionitis and preterm premature rupture of membranes. We aimed to investigate the roles of progesterone (P4) and a novel progesterone receptor, progesterone receptor membrane component 1 (PGRMC1), in the response of fetal membranes to U. parvum. Fetal membrane cells (amnion, chorion and decidua) were isolated and confirmed to be free of Mycoplasmataceae. Cells were treated with U. parvum (5x106 CFU), and adherence was quantified by qPCR. Amnion and chorion cells were transfected with scrambled siRNA or validated PGRMC1 siRNA for 72h. Cells were then treated with U. parvum for 4h with or without pretreatment with P4 (10-7 M) or ethanol for 1h. Interleukin-8 (IL-8), matrix metalloproteinase 9 (MMP9) and cyclooxygenase (COX-2) mRNA expression were quantified by qRT-PCR. Culture medium was harvested and analyzed for IL-8 and prostaglandin (PGE2) secretion by ELISA and MMP9 activity by zymography. U. parvum had a mean adherence of 15.0±0.6%, 16.9± 3.7% and 4.7±0.3% in cultured amnion, chorion and decidua cells, respectively. Exposure to U. parvum elicited significant inflammatory responses including induction of IL-8, COX-2, PGE2 and MMP9. A possible role of PGRMC1 was identified in the inhibition of U. parvum-stimulated COX-2 and MMP9 mRNA expression in chorion cells and MMP9 activity in amnion cells. On the other hand, it might enhance the U. parvum-stimulated IL-8 protein secretion in amnion cells. P4, mediated through PGRMC1, significantly inhibited U. Parvum-induced MMP9 mRNA and COX-2 mRNA expression in chorion cells. P4 appeared to attenuate U. parvum induced IL-8 mRNA expression in chorion cells, but this P4 effect might not mediated through PGRMC1. In summary, U. parvum preferentially adheres to and induces inflammatory responses in chorion and amnion cells. P4 and PGRMC1 appear to differentially modulate the inflammatory responses induced by U. parvum among amnion and chorion cells.


Assuntos
Membranas Extraembrionárias/metabolismo , Inflamação/metabolismo , Proteínas de Membrana/metabolismo , Progesterona/metabolismo , Receptores de Progesterona/metabolismo , Infecções por Ureaplasma/metabolismo , Ureaplasma , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Membranas Extraembrionárias/microbiologia , Feminino , Humanos , Inflamação/microbiologia , Interleucina-8/genética , Interleucina-8/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Gravidez
3.
Biol Reprod ; 94(5): 119, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27009041

RESUMO

Preterm premature rupture of membranes (PPROM) is often associated with intra-amniotic inflammation and infection. Current understanding of the pathogenesis of PPROM includes activation of pro-inflammatory cytokines and proteolytic enzymes leading to compromise of membrane integrity. The impact of exposure to bacterial pathogens, including Ureaplasma parvum, on gestational membranes is poorly understood. Our objective was to develop a dual-chamber system to characterize the inflammatory response of gestational membranes to U. parvum in a directional nature. Full-thickness human gestational membrane explants, with either choriodecidua or amnion oriented superiorly, were suspended between two washers in a cylindrical device, creating two distinct compartments. Brilliant green dye was introduced into the top chamber to assess the integrity of the system. Tissue viability was evaluated after 72 h using a colorimetric cell proliferation assay. Choriodecidua or amnion was exposed to three doses of U. parvum and incubated for 24 h. Following treatment, media from each compartment were used for quantification of U. parvum (quantitative PCR), interleukin (IL)-8 (enzyme-linked immunosorbent assay), and matrix metalloproteinase (MMP)-2 and MMP-9 activity (zymography). We observed that system integrity and explant viability were maintained over 72 h. Dose-dependent increases in recovered U. parvum, IL-8 concentration, and MMP-2 activity were detected in both compartments. Significant differences in IL-8 concentration and MMP-9 activity were found between the choriodecidua and amnion. This tissue explant system can be used to investigate the inflammatory consequences of directional bacterial exposure for gestational membranes and provides insight into the pathogenesis of PPROM and infectious complications of pregnancy.


Assuntos
Corioamnionite/microbiologia , Corioamnionite/patologia , Membranas Extraembrionárias/patologia , Complicações Infecciosas na Gravidez/patologia , Técnicas de Cultura de Tecidos/métodos , Infecções por Ureaplasma/patologia , Ureaplasma/fisiologia , Âmnio/metabolismo , Corioamnionite/metabolismo , Citocinas/metabolismo , Membranas Extraembrionárias/metabolismo , Feminino , Ruptura Prematura de Membranas Fetais/metabolismo , Ruptura Prematura de Membranas Fetais/patologia , Humanos , Mediadores da Inflamação/metabolismo , Modelos Biológicos , Gravidez , Complicações Infecciosas na Gravidez/metabolismo , Complicações Infecciosas na Gravidez/microbiologia , Técnicas de Cultura de Tecidos/instrumentação , Ureaplasma/isolamento & purificação , Infecções por Ureaplasma/metabolismo
4.
Anesth Analg ; 119(5): 1094-101, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25126705

RESUMO

BACKGROUND: Reports in the recent experimental literature have provided contradicting results in different animal species regarding the efficacy of IV lipid emulsion (ILE) in the reversal of cardiovascular and central nervous system symptoms of local anesthetic and other lipophilic drug overdoses. In particular, ILE seemed to be effective in rats, rabbits, dogs, and humans, but not in swine, for which it not only failed to reverse the adverse effects of anesthetics, but the animals also developed a generalized cutaneous mottling or a dusky appearance immediately after ILE, suggestive of another type of toxicity. The latter symptoms arise in complement (C) activation-related pseudoallergy, a hypersensitivity reaction to particulate drugs and agents. METHODS: Ten Yorkshire swine (15-20 kg) were sedated with ketamine and anesthetized with isoflurane. ILE 1.5 and 5 mL/kg 20% was administered via the ear vein while pulmonary arterial pressure, systemic arterial blood pressure, electrocardiogram, and end-tidal CO2 were recorded continuously. Thromboxane was measured in blood collected at baseline and 2 and 10 minutes after injections. Complement activation by lipid emulsion was also assessed in vitro with soluble terminal complement complex (SC5b-9) and sheep red blood cell assays. RESULTS: Significant increases were observed in the pulmonary pressure (median [interquartile range]) within minutes after the administration of ILE, both at doses 1.5 and 5 mL/kg (15 [12-16.5] to 18.5 [16-20] mm Hg, P = 0.0058 and 15.5 [13-17.25] to 39.5 [30.5-48.5], respectively). The systemic arterial blood pressure increased, and the heart rate decreased after both injections. Thromboxane B2 concentration (median [interquartile range]) in the blood plasma increased from a baseline of 617.3 [412.4-920] to 1132 [597.9-1417] pg/mL (P = 0.0055) and from 1276 [1200-2581] to 4046 [2946-8442] pg/mL (P = 0.0017) after the administration of 1.5 and 5 mL/kg ILE, respectively. Intralipid did not cause in vitro complement activation in human serum. CONCLUSIONS: ILE causes clinically significant hemodynamic changes in pigs, in concert with significant increases in the plasma thromboxane concentration. However, the in vitro tests did not confirm involvement of the complement system in human sera, leaving the underlying mechanism of these findings in doubt. Nonetheless, the observed hemodynamic and biochemical effects of ILE serve as a caveat that the pig is not an ideal model for the study of interventions involving ILE.


Assuntos
Hipersensibilidade a Drogas/imunologia , Hipersensibilidade a Drogas/fisiopatologia , Emulsões Gordurosas Intravenosas/efeitos adversos , Anafilaxia/etiologia , Animais , Ativação do Complemento/efeitos dos fármacos , Toxidermias/etiologia , Toxidermias/imunologia , Hemodinâmica/efeitos dos fármacos , Ressuscitação , Suínos , Tromboxano B2/sangue
5.
A A Case Rep ; 3(2): 23-6, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25611019

RESUMO

A 30-year-old man developed unexplained rhabdomyolysis, persistently increased creatine kinase and severe debilitating muscle cramps. After a nondiagnostic neurologic evaluation, he was referred for a muscle biopsy, to include histology/histochemistry, a myoglobinuria panel, and a caffeine halothane contracture test. Only the caffeine halothane contracture test was positive, and a subsequent ryanodine receptor type 1 gene evaluation revealed a mutation functionally causative for malignant hyperthermia. His identical twin brother, who was suffering from similar complaints, was found to share the same mutation. They each require oral dantrolene therapy to control symptoms, despite difficulty in identifying health care providers familiar with treating this disorder.

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