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1.
Clin Transl Oncol ; 24(1): 127-144, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34370182

RESUMO

Metaplastic breast carcinoma (MBC) is a rare breast cancer subtype with rapid growth, high rates of metastasis, recurrence and drug resistance, and diverse molecular and histological heterogeneity. Patient-derived xenografts (PDXs) provide a translational tool and physiologically relevant system to evaluate tumor biology of rare subtypes. Here, we provide an in-depth comprehensive characterization of a new PDX model for MBC, TU-BcX-4IC. TU-BcX-4IC is a clinically aggressive tumor exhibiting rapid growth in vivo, spontaneous metastases, and elevated levels of cell-free DNA and circulating tumor cell DNA. Relative chemosensitivity of primary cells derived from TU-BcX-4IC was performed using the National Cancer Institute (NCI) oncology drug set, crystal violet staining, and cytotoxic live/dead immunofluorescence stains in adherent and organoid culture conditions. We employed novel spheroid/organoid incubation methods (Pu·MA system) to demonstrate that TU-BcX-4IC is resistant to paclitaxel. An innovative physiologically relevant system using human adipose tissue was used to evaluate presence of cancer stem cell-like populations ex vivo. Tissue decellularization, cryogenic-scanning electron microscopy imaging and rheometry revealed consistent matrix architecture and stiffness were consistent despite serial transplantation. Matrix-associated gene pathways were essentially unchanged with serial passages, as determined by qPCR and RNA sequencing, suggesting utility of decellularized PDXs for in vitro screens. We determined type V collagen to be present throughout all serial passage of TU-BcX-4IC tumor, suggesting it is required for tumor maintenance and is a potential viable target for MBC. In this study we introduce an innovative and translational model system to study cell-matrix interactions in rare cancer types using higher passage PDX tissue.


Assuntos
Antineoplásicos/uso terapêutico , Modelos Biológicos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Animais , Modelos Animais de Doenças , Xenoenxertos , Humanos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Mucosal Immunol ; 13(1): 64-74, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31597930

RESUMO

The seasonal burden of influenza coupled with the pandemic outbreaks of more pathogenic strains underscore a critical need to understand the pathophysiology of influenza injury in the lung. Interleukin-22 (IL-22) is a promising cytokine that is critical in protecting the lung during infection. This cytokine is strongly regulated by the soluble receptor IL-22-binding protein (IL-22BP), which is constitutively expressed in the lungs where it inhibits IL-22 activity. The IL-22/IL-22BP axis is thought to prevent chronic exposure of epithelial cells to IL-22. However, the importance of this axis is not understood during an infection such as influenza. Here we demonstrate through the use of IL-22BP-knockout mice (il-22ra2-/-) that a pro-IL-22 environment reduces pulmonary inflammation during H1N1 (PR8/34 H1N1) infection and protects the lung by promoting tight junction formation. We confirmed these results in normal human bronchial epithelial cells in vitro demonstrating improved membrane resistance and induction of the tight junction proteins Cldn4, Tjp1, and Tjp2. Importantly, we show that administering recombinant IL-22 in vivo reduces inflammation and fluid leak into the lung. Taken together, our results demonstrate the IL-22/IL-22BP axis is a potential targetable pathway for reducing influenza-induced pneumonia.


Assuntos
Inflamação/terapia , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/terapia , Interleucinas/metabolismo , Células Matadoras Naturais/imunologia , Pulmão/imunologia , Infecções por Orthomyxoviridae/terapia , Receptores de Interleucina/metabolismo , Junções Íntimas/patologia , Animais , Células Cultivadas , Humanos , Inflamação/imunologia , Influenza Humana/imunologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Terapia de Alvo Molecular , Infecções por Orthomyxoviridae/imunologia , Pneumonia , Receptores de Interleucina/genética , Transdução de Sinais , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Interleucina 22
3.
Respir Res ; 20(1): 184, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31416461

RESUMO

BACKGROUND: Influenza attacks the epithelium of the lung, causing cell death and disruption of the epithelial barrier leading to fluid buildup in the lung and impairment of gas exchange. Limited treatment options for severe influenza pneumonia prioritize the need for the discovery of effective therapies. IL-22 is a cytokine that promotes tissue integrity and has strong promise as a treatment option. While research has been focused on the cytokine itself, there is limited understanding of the regulation of the IL-22 receptor (IL-22Ra1) at the epithelial surface during infection. METHODS: IL-22Ra1 levels were measured by qRT-PCR, western blot and immunofluorescence following H1N1 influenza infection (A/PR/8/34 H1N1) or synthetic TLR3 mimetic, Poly (I:C). Regulation of the receptor was determined using STAT inhibitors (STAT1, STAT3 and PanSTAT inhibitors), TLR3 inhibition, and neutralization of interferon alpha receptor 2 (IFNAR2). Significance was determined by a p-value of greater than 0.05. Significance between two groups was measured using unpaired t-test and significance between more than two groups was measured using one-way ANOVA with Tukey Multiple Comparison Test. RESULTS: Here we show both in vivo and in vitro that IL-22Ra1 was induced as early as 24 h after influenza (H1N1 PR8) infection. This induction was triggered by toll-like receptor 3 (TLR3) as a TLR3 mimetic [Poly (I:C)] also induced IL-22Ra1 and inhibition of endosomal formation required for TLR3 function inhibited this process. This upregulation was dependent upon IFNß signaling through STAT1. Importantly, induction of IL-22Ra1 significantly increased IL-22 signaling as evidenced by pSTAT3 levels following IL-22 treatment. CONCLUSION: Collectively, these data suggest epithelial cells may optimize the beneficial effects of IL-22 through the induction of the IL-22 receptor during viral infection in the lung.


Assuntos
Influenza Humana/metabolismo , Receptores de Interleucina/biossíntese , Fator de Transcrição STAT1/biossíntese , Receptor 3 Toll-Like/biossíntese , Células A549 , Animais , Cloroquina/farmacologia , Humanos , Influenza Humana/patologia , Interferons/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Poli I-C/farmacologia
4.
J Thromb Haemost ; 15(8): 1607-1619, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28581694

RESUMO

Essentials Type 2N von Willebrand disease involves impaired von Willebrand factor to factor VIII binding. Type 2N von Willebrand disease mutations exhibit qualitative and mild quantitative deficiencies. Type 2N von Willebrand disease mice exhibit unstable venous hemostatic thrombi. The factor VIII-binding ability of von Willebrand factor regulates arteriole thrombosis dynamics. SUMMARY: Background von Willebrand factor (VWF) and factor VIII (FVIII) circulate as a non-covalent complex, with VWF serving as the carrier for FVIII. VWF indirectly influences secondary hemostasis by stabilizing FVIII and transporting it to the site of primary hemostasis. Type 2N von Willebrand disease involves impaired binding of VWF to FVIII, resulting in decreased plasma levels of FVIII. Objectives In these studies, we characterize the impact of three type 2N VWD variants (R763A, R854Q, R816W) on VWF secretion, FVIII stabilization and thrombus formation in a murine model. Methods Type 2N VWD mice were generated by hydrodynamic injections of mutant murine VWF cDNAs and the influence of these variants on VWF secretion and FVIII binding was evaluated. In vivo hemostasis and the dynamics of thrombus formation and embolization were assessed using a murine tail vein transection hemostasis model and an intravital thrombosis model in the cremaster arterioles. Results Type 2N VWD variants were associated with decreased VWF secretion using cell and animal-based models. FVIII-binding to type 2N variants was impaired in vitro and was variably stabilized in vivo by expressed or infused 2N variant VWF protein. Both transgenic type 2N VWD and FVIII knockout (KO) mice demonstrated impaired thrombus formation associated with decreased thrombus stability. Conclusions The type 2N VWD phenotype can be recapitulated in a murine model and is associated with both quantitative and qualitative VWF deficiencies and impaired thrombus formation. Patients with type 2N VWD may have normal primary hemostasis formation but decreased thrombus stability related to ineffective secondary hemostasis.


Assuntos
Fator VIII/metabolismo , Hemostasia , Trombose/sangue , Doença de von Willebrand Tipo 2/sangue , Fator de von Willebrand/metabolismo , Animais , Modelos Animais de Doenças , Fator VIII/genética , Células HEK293 , Hemostasia/genética , Humanos , Cinética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ligação Proteica , Estabilidade Proteica , Trombose/genética , Transfecção , Doença de von Willebrand Tipo 2/genética , Fator de von Willebrand/genética
5.
Harm Reduct J ; 14(1): 18, 2017 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-28494774

RESUMO

BACKGROUND: The perspectives of people who use drugs are critical in understanding why people choose to reduce harm in relation to drug use, what practices are considered or preferred in conceptualizations of harm reduction, and which environmental factors interfere with or support the use of harm reduction strategies. This study explores how people who inject drugs (PWID) think about harm reduction and considers the critical imperative of equity in health and social services delivery for this community. METHODS: This community-based participatory research study was conducted in a Canadian urban centre. Using a peer-based recruitment and interviewing strategy, semi-structured qualitative interviews were conducted by and with PWID. The Vidaview Life Story Board, an innovative tool where interviewers and participant co-construct a visual "life-scape" using a board, markers, and customized picture magnets, was used to facilitate the interviews. The topics explored included injection drug use and harm reduction histories, facilitators and barriers to using harm reduction strategies, and suggestions for improving services and supports. RESULTS: Twenty-three interviews with PWID (14 men and 9 women) were analysed, with a median age of 50. Results highlighted an expanded conceptualization of harm reduction from the perspectives of PWID, including motivations for adopting harm reduction strategies and a description of harm reduction practices that went beyond conventional health-focused concerns. The most common personal practices that PWID used included working toward moderation, employing various cognitive strategies, and engaging in community activities. The importance of social or peer support and improving self-efficacy was also evident. Further, there was a call for less rigid eligibility criteria and procedures in health and social services, and the need to more adequately address the stigmatization of drug users. CONCLUSIONS: These findings demonstrated that PWID incorporate many personal harm reduction practices in their daily lives to improve their well-being, and these practices highlight the importance of agency, self-care, and community building. Health and social services are needed to better support these practices because the many socio-structural barriers this community faces often interfere with harm reduction efforts. Finally, "one size does not fit all" when it comes to harm reduction, and more personalized or de-medicalized conceptualizations are recommended.


Assuntos
Pesquisa Participativa Baseada na Comunidade/métodos , Usuários de Drogas , Redução do Dano , Abuso de Substâncias por Via Intravenosa/terapia , Canadá , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Autocuidado/métodos
6.
Poult Sci ; 84(10): 1533-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16335121

RESUMO

Enrichment of eggs with folate is possible when dietary folic acid levels are increased. However, development of optimal strategies for the production of folate-enriched eggs requires knowledge as to differences due to strain of bird and a greater understanding of the factors limiting egg folate deposition. To this end, a study was designed to determine the response of two leghorn strains that differ in production performance. Hyline W36 and W98 hens (n = 6 per diet) received a barley-based ration containing 0, 2, 4, 8, 16, 32, 64, or 128 mg/kg of crystalline folic acid for 21 d. Response criteria included production parameters, measures of blood folate status, and egg folate content. Significant (P < 0.05) main effects of folate supplementation were observed for egg folate content and plasma folate, which increased, and homocysteine concentrations, which decreased with supplementation; performance, however, was not affected. The Hyline W98 strain had significantly (P < 0.05) higher total egg and yolk weights and feed consumption when compared with the W36. Significant (P < 0.05) ration x strain interactions were observed for egg and yolk weight, egg folate content, and plasma homocysteine. The higher egg mass producing strain, Hyline W98, benefited from increased folic acid through a reduction in plasma homocysteine concentrations, suggesting that this strain has a higher requirement for folate than the W36 strain. Overall, egg folate content is maximized when crystalline folic acid is supplemented to the diet at 2 mg/kg or higher. Higher levels of egg folate are not achieved due to the saturation of the precursor pool for egg folate deposition.


Assuntos
Galinhas/classificação , Galinhas/fisiologia , Suplementos Nutricionais , Gema de Ovo/química , Ácido Fólico/administração & dosagem , Ácido Fólico/análise , Ração Animal , Animais , Dieta , Relação Dose-Resposta a Droga , Feminino , Ácido Fólico/farmacologia , Oviposição/fisiologia
7.
Theriogenology ; 63(4): 1081-91, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15710195

RESUMO

The banteng (Bos javanicus), a member of the bovidae family, is currently listed as threatened by the IUCN Red List and it is estimated the total world population is <10,000 animals. In exotic or endangered species, the lack of oocytes and recipients precludes the use of traditional somatic cell nuclear transfer (NT), and an approach such as interspecies NT may be the only alternative to produce embryos and offspring. A total of 348 enucleated domestic bovine oocytes were reconstructed with either male (Treatment A) or female (Treatment B) adult banteng fibroblasts and a total of 103 bovine oocytes were parthenogenically activated as a control (Treatment C). There was no significant difference in fusion rate (68 versus 77%) between Treatments A and B. Of fused couplets, those in Treatment A had greater (P < 0.05) cleavage (67 versus 51%) and blastocyst (28 versus 15%) rate than Treatment B. Of a total of 24 blastocysts transferred into 12 domestic cattle recipients from Treatment A, two pregnancies (17%) were established with heart beats detectable at 30 day by rectal ultrasonography. No pregnancies resulted from the transfer of 14 blastocysts from Treatment B. Both pregnancies were subsequently lost, one between 30 and 60 days and the second between 60 and 90 days of gestation. The bovine cytoplast supported mitotic cleavage of banteng karyoplasts, and was capable of reprogramming the nucleus to achieve blastocyst stage embryos and pregnancies in exotic bovids.


Assuntos
Técnicas de Transferência Nuclear , Técnicas Reprodutivas/veterinária , Ruminantes/embriologia , Animais , Blastocisto , Bovinos , Conservação dos Recursos Naturais , Técnicas de Cultura Embrionária , Transferência Embrionária , Feminino , Fibroblastos/ultraestrutura , Masculino , Gravidez , Transplante Heterólogo
8.
J Appl Psychol ; 84(3): 362-75, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10380417

RESUMO

This study examined whether participants were sensitive to variations in the quality of an experiment discussed by an expert witness and whether they used heuristic cues when evaluating the expert evidence. In the context of a hostile work environment case, different versions of the expert testimony varied the presence of heuristic cues (i.e., whether the expert's research was generally accepted or ecologically valid) and evidence quality (i.e., the construct validity of the expert's research). Men who heard expert testimony were more likely to find that the plaintiff's workplace was hostile than were men who did not hear the expert testimony; expert testimony did not influence women's liability judgments. Heuristic cues influenced participant evaluations of the expert testimony validity, but evidence quality did not. Cross-examination did not increase juror sensitivity to evidence quality. Implications for science in the legal system are discussed.


Assuntos
Direito Penal , Tomada de Decisões , Prova Pericial , Hostilidade , Trabalho , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ciência , Fatores Sexuais
9.
Memory ; 6(3): 257-75, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9709442

RESUMO

We explored the relation between output order and the likelihood of a commission error in free recall under both laboratory and eyewitness conditions. In Experiment 1, participants studied a list of 20 unrelated words and, after a five-minute distractor task, were asked to recall those words. Whereas the items that participants recalled were mostly correct, commission errors were more likely to occur at the end of a participant's output. In Experiment 2, participants viewed a police film depicting an armed robbery. Participants described the perpetrators, their truck, and the sequence of events during the robbery. When describing the perpetrators or the truck, commission errors were more likely to occur at the end of the output. However, when describing the sequence of events, commission errors were more likely to occur in the middle of the output. In Experiment 3, we replicated the finding that commission errors are likely to occur at the end of the output order when participants are describing people. We speculate on the potential application of this finding and its theoretical underpinnings.


Assuntos
Vítimas de Crime , Rememoração Mental/fisiologia , Análise de Variância , Humanos , Testes Neuropsicológicos , Testes Psicológicos , Sensibilidade e Especificidade
10.
Heart Dis Stroke ; 3(4): 196-200, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7921663

RESUMO

The Swan-Ganz catheter provides a relatively easy means of obtaining a wealth of information about intracardiac pressures and flows. The catheter also is useful for intracardiac pacing. Because any invasive procedure entails some risk, albeit small in the case of the Swan-Ganz catheter, insertion of a catheter usually is reserved for hemodynamically unstable patients and/or those in whom information relevant to clinical management can be obtained only by this means. In such circumstances the catheter has been extraordinarily useful, and further refinements undoubtedly will make it even more useful in the future.


Assuntos
Cateterismo de Swan-Ganz , Hemodinâmica/fisiologia , Estimulação Cardíaca Artificial , Cateterismo de Swan-Ganz/efeitos adversos , Cateterismo de Swan-Ganz/instrumentação , Cateterismo de Swan-Ganz/métodos , Humanos , Monitorização Fisiológica , Valores de Referência
11.
Psychopharmacology (Berl) ; 115(1-2): 180-4, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7862893

RESUMO

Recently, a rodent model of nicotine abstinence syndrome has been developed based on observing the frequency of spontaneous behavioral signs following termination of continuous subcutaneous infusion of nicotine tartrate. In the present study, the nicotinic antagonist mecamylamine precipitated an abstinence syndrome in nicotine-dependent rats. Twelve rats were each infused for 7 days with 9 mg/kg per day nicotine tartrate in saline via Alzet osmotic minipumps; another 12 rats were sham-operated and remained nicotine-naive. Six rats from each group received 1 mg/kg mecamylamine in saline SC immediately before a 30-min observation, while the remaining six rats from each group received saline alone. Nicotine-infused rats receiving mecamylamine exhibited significantly more (P < 0.01), overall abstinence signs than all other groups. In terms of categories of signs, they displayed significantly more gasps/writhes, teeth chatter/chews, shakes/tremors and ptosis. In a second experiment utilizing only nicotine-naive rats, a far higher dose of mecamylamine (5 mg/kg sc) induced a quasi-nicotine abstinence syndrome. The results provide further validation for this rodent model of nicotine abstinence syndrome.


Assuntos
Mecamilamina/farmacologia , Nicotina/efeitos adversos , Antagonistas Nicotínicos/farmacologia , Síndrome de Abstinência a Substâncias/psicologia , Animais , Comportamento Animal/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Transtornos Relacionados ao Uso de Substâncias/psicologia
12.
Chest ; 103(1): 226-31, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8417884

RESUMO

To assess the prevalence and severity of Doppler-detected valvular regurgitation, as assessed by multiple Doppler modalities, in patients with structurally normal hearts, we analyzed Doppler echocardiograms in a consecutive sample of 206 referred patients who were found to have completely normal M-mode and two-dimensional echocardiograms. Valvular regurgitation was detected by Doppler in 94 percent, and 56 percent had regurgitation in at least two valves (mitral, tricuspid, and/or aortic). Mitral, tricuspid, and aortic regurgitation was detected in 73 percent, 68 percent, and 12 percent, respectively, with moderate regurgitation occurring in 6 percent, 5 percent, and 2 percent, respectively. The presence of mitral and tricuspid regurgitation was not related to age, although the prevalence of moderate regurgitation was three times more prevalent (p < 0.05) in those > 50 years old compared with those < or = 50 years. Aortic regurgitation was two to three times more prevalent (p < 0.01) in patients > 50 years compared with younger subjects, and moderate aortic regurgitation was three times more prevalent in older patients. Of those with measurable right-sided cardiac pressures, estimated right atrial pressure was < 10 mm Hg in 93 percent of patients, and estimated pulmonary artery systolic pressure was < or = 30 mm Hg in 57 percent of patients. Estimated right atrial pressure was > 10 mm Hg in only 7 percent, and only 13 percent had estimated pulmonary artery systolic pressure > or = 40 mm Hg. These data indicate a very high prevalence of trivial and mild mitral and tricuspid regurgitation in patients with otherwise "normal" hearts, suggesting that these findings are physiologically normal. These data should be considered when addressing management in patients with Doppler-detected valvular regurgitation in order to prevent "iatrogenic heart disease."


Assuntos
Insuficiência da Valva Aórtica/diagnóstico por imagem , Função do Átrio Direito/fisiologia , Pressão Sanguínea/fisiologia , Ecocardiografia Doppler , Ecocardiografia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Função Ventricular Direita/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Insuficiência da Valva Aórtica/fisiopatologia , Estudos de Coortes , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/fisiopatologia , Prevalência , Artéria Pulmonar/diagnóstico por imagem , Estudos Retrospectivos , Insuficiência da Valva Tricúspide/fisiopatologia , Veia Cava Inferior/diagnóstico por imagem
13.
Neurosci Lett ; 146(2): 203-6, 1992 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-1491790

RESUMO

Previous studies suggest that neuropeptide FF (NPFF) plays a role in opiate dependence and subsequent abstinence syndrome. Endogenous NPFF also appears to play a role in opiate tolerance since third ventricle injection of IgG from NPFF antiserum selectively restores morphine sensitivity in morphine-tolerant rats. The NPFF analog, desamino YFLFQPQRamide (daY8Ra) has previously antagonized behavioral effects of NPFF and has attenuated morphine dependence. The present study assessed whether daY8Ra could similarly attenuate morphine tolerance. Third ventricle (i.c.v.) injection of daY8Ra restored the analgesic response to i.c.v. morphine in morphine-tolerant rats (radiant heat tail flick test). Saline injection failed to produce this effect. In opiate-naive rats, however, the same treatment with daY8Ra did not affect the analgesic response to i.c.v. morphine. Thus, daY8Ra appears to selectively restore morphine sensitivity in opiate-tolerant animals. These results further support the hypothesis that endogenous NPFF contributes to opiate tolerance.


Assuntos
Morfina/farmacologia , Oligopeptídeos/farmacologia , Sequência de Aminoácidos , Animais , Tolerância a Medicamentos , Injeções Intraventriculares , Dados de Sequência Molecular , Oligopeptídeos/imunologia , Ratos
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