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1.
Cancer Immunol Immunother ; 66(5): 593-603, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28224210

RESUMO

Regulatory T cells (Treg) hamper anti-tumor T-cell responses resulting in reduced survival and failure of cancer immunotherapy. Among lymphoid organs, the bone marrow (BM) is a major site of Treg residence and recirculation. However, the process governing the emigration of Treg from BM into the circulation remains elusive. We here show that breast cancer patients harbour reduced Treg frequencies in the BM as compared to healthy individuals or the blood. This was particularly the case for tumor antigen-specific Treg which were quantified by MHCII tumor peptide loaded tetramers. We further demonstrate that decreased Treg distribution in the BM correlated with increased Treg redistribution to tumor tissue, suggesting that TCR triggering induces a translocation of Treg from the BM into tumor tissue. Sphingosine-1-phosphate receptor 1 (S1P1)-which is known to mediate exit of immune cells from lymphoid organs was selectively expressed by tumor antigen-specific BM Treg. S1P1 expression could be induced in Treg by BM-resident antigen-presenting cells (BMAPCs) in conjunction with TCR stimulation, but not by TCR stimulation or BMAPCs alone and triggered the migration of Treg but not conventional T cells (Tcon) to its ligand Sphingosine-1-phosphate (S1P). Interestingly, we detected marked S1P gradients between PB and BM in breast cancer patients but not in healthy individuals. Taken together, our data suggest a role for S1P1 in mediating the selective mobilization of tumor specific Treg from the BM of breast cancer patients and their translocation into tumor tissue.


Assuntos
Células da Medula Óssea/imunologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Receptores de Lisoesfingolipídeo/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Regulação para Cima
2.
Microsurgery ; 36(6): 491-500, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26716599

RESUMO

BACKGROUND: Due to their unique properties, adipose derived stem cells (ADSCs) obtain promising potential to enhance nerve regeneration. The aim of this study was to investigate if fibrin-glue embedded ADSCs were a beneficial adjunct to primary coaptation in a rat sciatic nerve model. MATERIALS AND METHODS: Fifty male Lewis rats underwent sciatic nerve transection and subsequent epineural suture repair. The treatment group received ADSCs re-suspended in fibrin glue, while the control group received fibrin glue only. After 7, 21, 35, and 63 days, analysis involved axon count, myelin sheath thickness as well as N- and G-ratios. Additionally, muscle weight quotient (operated vs. non-operated site of the same animal) was calculated and compared between treatment and control groups. For co-detection of vital ADSCs, vessel walls, and Schwann cells, immunolabeling was performed with CM-DiI, SMA, and S-100 antibodies, respectively. RESULTS: ADSCs led to a significant increase of myelinization at day 21 (0.508 ± 0.085 µm vs. 0.381 ± 0.044 µm, P = 0.025) and day 35 (0.872 ± 0.09 µm vs. 0.495 ± 0.078 µm; P = 0.01) after surgery. Axon count was significantly increased at day 21 (420 ± 119 vs. 129 ± 63; P = 0.003) and day 63 (284 ± 137 vs. 111 ± 26; P = 0.046) after surgery. N- and G-ratios were significantly different compared with control indicating enhanced nerve regeneration due to ADSC treatment at each time point (P < 0.05). Muscle weight quotient was significantly higher in the treatment group compared with the control at day 21 (44.01% ± 6.16% vs. 35.03% ± 2.61%; P = 0.014) and day 63 (65.49% ± 2.81% vs. 58.79% ± 4.06%; P = 0.009) after surgery. Co-detection of immunolabeled cells showed vital ADSCs at the neuronal repair site and in close proximity to intraneuronal vessels indicating active participation of ADSCs in the process of nerve regeneration and associated angiogenesis. CONCLUSION: ADSCs embedded in a fibrin matrix can significantly enhance regeneration of peripheral nerve injuries after primary coaptation. © 2015 Wiley Periodicals, Inc. Microsurgery 36:491-500, 2016.


Assuntos
Adesivo Tecidual de Fibrina , Transplante de Células-Tronco Mesenquimais/métodos , Regeneração Nervosa/fisiologia , Traumatismos dos Nervos Periféricos/cirurgia , Nervo Isquiático/lesões , Técnicas de Sutura , Adesivos Teciduais , Animais , Terapia Combinada , Masculino , Traumatismos dos Nervos Periféricos/fisiopatologia , Ratos , Ratos Endogâmicos Lew , Nervo Isquiático/fisiologia , Nervo Isquiático/cirurgia , Gordura Subcutânea/citologia , Resultado do Tratamento
3.
Contemp Clin Trials ; 131: 107268, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37321352

RESUMO

BACKGROUND: Suicide is a leading cause of death in adolescents and adults in the US. Follow-up support delivered when patients return home after an emergency department (ED) or primary care encounter can significantly reduce suicidal ideation and attempts. Two follow-up models to augment usual care including the Safety Planning Intervention have high efficacy: Instrumental Support Calls (ISC) and Caring Contacts (CC) two-way text messages, but they have never been compared to assess which works best. This protocol for the Suicide Prevention Among Recipients of Care (SPARC) Trial aims to determine which model is most effective for adolescents and adults with suicide risk. METHODS: The SPARC Trial is a pragmatic randomized controlled trial comparing the effectiveness of ISC versus CC. The sample includes 720 adolescents (12-17 years) and 790 adults (18+ years) who screen positive for suicide risk during an ED or primary care encounter. All participants receive usual care and are randomized 1:1 to ISC or CC. The state suicide hotline delivers both follow-up interventions. The trial is single-masked, with participants unaware of the alternative treatment, and is stratified by adolescents/adults. The primary outcome is suicidal ideation and behavior, measured using the Columbia Suicide Severity Rating Scale (C-SSRS) screener at 6 months. Secondary outcomes include C-SSRS at 12 months, and loneliness, return to crisis care for suicidality, and utilization of outpatient mental health services at 6 and 12 months. DISCUSSION: Directly comparing ISC and CC will determine which follow-up intervention is most effective for suicide prevention in adolescents and adults.


Assuntos
Suicídio , Envio de Mensagens de Texto , Adolescente , Adulto , Humanos , Serviço Hospitalar de Emergência , Atenção Primária à Saúde , Ideação Suicida , Suicídio/psicologia , Prevenção do Suicídio , Ensaios Clínicos Pragmáticos como Assunto
4.
AIDS Educ Prev ; 34(5): 379-394, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36181499

RESUMO

Stressful life events are prevalent among justice-involved populations and are associated with sexual risk behaviors and partner communication regarding safe-sex practices. We describe patterns of stress exposure for heterosexual couples (where males are under community supervision) and how stress patterns are associated with sexual risk behaviors and communication (460 individuals; 230 couples). Latent class analysis identified patterns of stress. Multinominal logistic regression models identified associations between sex, race, ethnicity, and stress classes. Multilevel Poisson regression models described relationships between sexual risk behaviors and frequency of communication about condoms/HIV, and stress classes. We found four classes that differed by sex, race, and ethnicity and were associated with the number of sexual partners, condom use self-efficacy, discussing condoms with partner, and discussing HIV prevention with partner. Partner class was associated with the number of sexual partners. Findings inform future assessment/interventions for sexual health that consider patterns of stress and demographics.


Assuntos
Infecções por HIV , Parceiros Sexuais , Comunicação , Preservativos , Feminino , Infecções por HIV/prevenção & controle , Humanos , Masculino , Assunção de Riscos , Comportamento Sexual , Justiça Social
5.
J Org Chem ; 76(2): 645-53, 2011 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21190365

RESUMO

Dications of 9-(3-phenyl-1H-inden-1-ylidene)-5H-dibenzo[a,d]cycloheptene, 5(2+), were prepared by oxidation with SbF(5) in SO(2)ClF, and their magnetic behavior was compared to dications of 9-(3-phenyl-1H-inden-1-ylidene)-9H-fluorene, 2(2+). The good correlation between the experimental (1)H NMR shifts for the dications that were oxidized cleanly and the chemical shifts calculated by the GAIO method supported the use of the nucleus independent chemical shifts, NICS, to evaluate the antiaromaticity of the indenyl systems of 2(2+)/5(2+) and their unsubstituted parent compounds, 6(2+) and 7(2+), as well as the antiaromaticity of the fluorenyl system of 2(2+)/7(2+) and the aromaticity of the dibenzotropylium system of 5(2+)/6(2+). Antiaromaticity was shown to be directly related to the amount of charge in the antiaromatic systems, with the antiaromatic systems more responsive to changes in the calculated NBO charge than the aromatic systems. The antiaromaticity was also shown to be directly related to the amount of delocalization in the ring system. The aromaticity of the dibenzotropylium system was much less responsive to changes in the amount of charge in the tropylium system, because the aromatic system was much more completely delocalized. Thus, antiaromatic species are more sensitive probes of delocalization than aromatic ones.

6.
Platelets ; 21(3): 221-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20158381

RESUMO

Platelet dysfunction is an important cause of bleeding early after cardiac surgery. Whole-blood multiple electrode aggregometry (MEA), investigating the adhesion and aggregation of activated platelets onto metal electrodes, has shown correlations with platelet concentrates transfusion in this setting. Platelet activity in vivo is dependent on shear stress, an aspect that cannot be investigated with MEA, but with the cone and plate(let) analyzer (CPA) Impact-R that measures the interaction of platelets and von Willebrand factor (vWF) in whole blood under shear. We hypothesized that preoperative CPA may show better correlation with platelet concentrates transfusion post-cardiac surgery than MEA, since it is dependent on both platelet activity and platelet interaction with vWF multimers. Blood was obtained preoperatively from 30 patients undergoing aorto-coronary bypass (ACB) and 20 patients with aortic valve (AV) surgery. MEA was performed in hirudin-anticoagulated blood. The Impact-R analyses were performed in blood anticoagulated with hirudin, heparin or the standard anticoagulant citrate. For the light microscopy images obtained, the parameter surface coverage (SC) was calculated. Preoperative Impact-R results were abnormally decreased in AV patients and significantly lower than in ACB patients. For the Impact-R analysis performed in citrated blood, no correlation with platelet concentrates transfusion was observed. In contrast, MEA was comparable between the groups and correlated significantly with intraoperative platelet concentrates transfusion in both groups (rho between -0.47 and -0.62, p < 0.05). Multiple electrode aggregometry appeared more useful and easier to apply than CPA for preoperatively identifying patients with platelet concentrates transfusion in cardiac surgery.


Assuntos
Plaquetas/fisiologia , Ponte de Artéria Coronária , Agregação Plaquetária , Transfusão de Plaquetas , Sistemas Automatizados de Assistência Junto ao Leito , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Plaquetas/citologia , Adesão Celular , Eletrodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Plaquetária/instrumentação , Testes de Função Plaquetária/métodos , Transfusão de Plaquetas/efeitos adversos , Adulto Jovem , Fator de von Willebrand/metabolismo
7.
Glob Public Health ; 15(12): 1810-1819, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32633696

RESUMO

The community-based disaster risk management (CBDRM) framework recognises the crucial role that small- and medium-sized NGOs play during adverse events, particularly in marginalised communities. Despite the global frequency of civil unrest, its effect on NGOs' programmatic, administrative, and operational capabilities is poorly understood. To this end, we completed in-depth semi-structured interviews with eight key informants representing seven health NGOs in Nicaragua several months after widespread and persistent civil unrest erupted in April 2018. Data analysis revealed that all NGOs experienced notable disruptions in community education and health promotion, healthcare provision, fundraising, and strategic planning. Further, NGOs experienced several key challenges in responding to crises, including mobility within and between communities, diminishing financial resources, and safety concerns for staff and volunteers. Several NGOs anticipated long-term adverse impacts. In light of these challenges, we propose that health NGOs create a plan of action to mitigate adverse impacts of civil unrest and promote population health. Specifically, a plan of action should address institutional planning, communication strategies, and partnerships and coalitions. We also propose important ways in which future research could build on this preliminary study.


Assuntos
Distúrbios Civis , Atenção à Saúde , Organizações , Atenção à Saúde/organização & administração , Humanos , Nicarágua
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