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1.
J Pediatr Psychol ; 47(5): 606-616, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35552431

RESUMO

OBJECTIVE: Living with a child with a life-limiting condition (LLC), for which there is no hope of cure and premature death is expected, places much stress on a family unit. Familial communication has the potential to serve as a buffer when children are faced with stressful situations. The overall aim of the study was to learn more about illness-related communication between parents and well-siblings, giving particular consideration to the amount of illness-related communication, and sibling satisfaction with familial communication. METHODS: Participants included 48 well-siblings (aged 6-21 years) of children with LLCs and their parents. Parents and well-siblings independently completed validated measures of familial communication and sibling functioning. Parents also provided demographic information and completed a questionnaire assessing amount of illness-related information provided to well-siblings. RESULTS: Parents reported that 47.8% of well-siblings never or rarely initiated conversations about their sibling's illness. Moreover, 52.2% of well-siblings never or rarely spoke about death. Amount of illness-related communication between parents and well-siblings was most strongly predicted by parental resilience and well-sibling age. Parents engaged in significantly more illness-related communication with girls than boys (t(44)=-2.28, p = .028). Well-siblings (p < .01) and parents (p < .05) rated satisfaction with familial communication significantly higher than published norms. The only significant predictor of well-sibling satisfaction with familial communication was greater familial cohesion. Family communication variables were not significantly correlated with measures of sibling functioning (all p's>.05). CONCLUSIONS: This study provides new information regarding parent and well-sibling communication in families who have a child with a LLC.


Assuntos
Pais , Irmãos , Criança , Comunicação , Família , Feminino , Humanos , Masculino , Inquéritos e Questionários
2.
Child Care Health Dev ; 48(2): 269-276, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34766366

RESUMO

BACKGROUND: Living with a child who has a life-limiting condition (LLC) is likely to have a major impact on all family members. There is a need to have a clearer understanding of the nature and extent of this impact on parents and well-siblings. The current study aimed to investigate the psychosocial functioning of well-siblings and parents living with a child with an LLC. Further, the study aimed to assess the resilience resources of both well-siblings and parents, giving consideration to how these relate to psychosocial functioning. METHODS: Participants included 48 well-siblings (6-21 years) and 42 parents of children with LLCs. Parents and well-siblings independently completed validated measures of child and adult functioning and personal resilience. Parents provided demographic information about the patient and family. RESULTS: The emotional, social and school functioning of well-siblings in the current study was found to be significantly poorer than published norms (all p's < .01). Parental self-reported depression, anxiety and stress scores were also all significantly poorer than published norms (all p's < .01). There was negligible agreement between well-sibling self-reported functioning and parental proxy-report of the well-siblings functioning (all r's < .126, all p's > .464). Sibling self-reported resilience was positively correlated with each of the measures of psychosocial functioning (all r's > .318, p's < .05). Parental resilience was significantly negatively correlated with depressive symptoms (r = -.369, p < .05) and anxiety symptoms (r = -.473, p < .01) but not stress scores (r = -.074, p = .644). CONCLUSION: Family members living with a child who has an LLC were found to have significantly poorer psychosocial functioning than published norms. Although one cannot infer a causal direction from the current study, greater self-reported well-sibling and parental resilience were associated with aspects of better self-reported psychosocial functioning. Future studies should assess the impact of psychosocial interventions aimed at enhancing the resilience and functioning of both well-siblings and parents.


Assuntos
Pais , Irmãos , Adulto , Criança , Família , Humanos , Pais/psicologia , Funcionamento Psicossocial , Autorrelato , Irmãos/psicologia
3.
Qual Inq ; 27(7): 835-843, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38603088

RESUMO

In this article, we "write-to" time from an autoethnographic perspective. Working intra-actively via a dialogic play script form, we collaboratively wonder about time during our experiences of COVID-19 as it relates to a compression of offline into online spaces. Presenting conversations we've had together over email, WhatsApp, and Google docs, with the reviewers of this Special Issue, and with scholarship, we foreground three main questions: What does time mean? How has our sense of time changed? And what is the link between these meanings and changes and the relationship between online and offline spaces?

4.
Dermatol Ther ; 33(6): e13933, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32609414

RESUMO

There is a paucity of high-quality evidence and guidelines on the prediction of skin defect reconstruction, and the type of repair rests on the operating surgeon's experience and skill. Mismatches between planning and execution can have negative consequences on resources, staff, and patient counseling. To investigate the factors that predict complex reconstruction in facial skin cancer surgery, we performed a retrospective study collecting information on the several parameters that may affect the method of reconstruction. A total of 325 cases were included. Only the factors tumor size (Z = 2.54; P < .05) and predicted repair plan (Z = 2.73; P < .01) were found to be significant predictors of complex repairs. When broken down by site and size, only the nose, scalp, and temple demonstrated a significant correlation between tumor size and the need for complex repairs. Clinical judgment at the time of initial examination is by far the greatest predictor of complex repairs. This occurs even when clinicians have heterogeneous surgical skills, and most are not technically versed in complex repairs. Increasing tumor size was also found to be an independent risk factor albeit only at certain body sites such as the temple, scalp, and nose.


Assuntos
Procedimentos de Cirurgia Plástica , Neoplasias Cutâneas , Humanos , Estudos Retrospectivos , Couro Cabeludo/cirurgia , Neoplasias Cutâneas/cirurgia , Transplante de Pele , Retalhos Cirúrgicos
5.
Mol Cell ; 45(4): 505-16, 2012 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-22365830

RESUMO

DNA double-strand break (DSB) signaling and repair are critical for cell viability, and rely on highly coordinated pathways whose molecular organization is still incompletely understood. Here, we show that heterogeneous nuclear ribonucleoprotein U-like (hnRNPUL) proteins 1 and 2 play key roles in cellular responses to DSBs. We identify human hnRNPUL1 and -2 as binding partners for the DSB sensor complex MRE11-RAD50-NBS1 (MRN) and demonstrate that hnRNPUL1 and -2 are recruited to DNA damage in an interdependent manner that requires MRN. Moreover, we show that hnRNPUL1 and -2 stimulate DNA-end resection and promote ATR-dependent signaling and DSB repair by homologous recombination, thereby contributing to cell survival upon exposure to DSB-inducing agents. Finally, we establish that hnRNPUL1 and -2 function downstream of MRN and CtBP-interacting protein (CtIP) to promote recruitment of the BLM helicase to DNA breaks. Collectively, these results provide insights into how mammalian cells respond to DSBs.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA por Junção de Extremidades , Ribonucleoproteínas Nucleares Heterogêneas/fisiologia , Proteínas Nucleares/fisiologia , Fatores de Transcrição/fisiologia , Hidrolases Anidrido Ácido , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Transporte/fisiologia , Proteínas de Ciclo Celular/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Endodesoxirribonucleases , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Humanos , Proteína Homóloga a MRE11 , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
J Neurosci Res ; 97(6): 698-707, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30746753

RESUMO

Traumatic brain injury (TBI) effects both the brain and the immune system. Circulating monocytes/macrophages (Mo /Ma ) after a TBI may play an important role in preserving the blood-brain barrier (BBB), reducing brain edema, and interacting with resident microglia. To elucidate the role of circulating Mo /Ma , we utilized a monocyte/macrophage depletion model in response to TBI in male rats. Clodronate liposomes (CL) were used to deplete circulating Mo /Ma . A controlled cortical impact (CCI) injury model was used to create a TBI. All animals received either CL or PBS liposomes (PL), 48 and 24 hr prior to the procedure, and were sacrificed 72 hr post-injury for analysis of BBB permeability, brain edema, whole blood (Mo /Ma and granulocytes), and/or microglial analysis. Animals undergoing Mo /Ma depletion with CL prior to CCI (CCI-CL) were found to have increased BBB permeability when compared to non-depleted CCI (CCI-PL) animals. At 72 hr following injury, Sham-CL maintained on average an 82% reduction in the whole blood monocytes when compared to Sham-PL (p < 0.001). Monocytes in the whole blood remained significantly lower in CCI-CL animals when compared to CCI-PL (p < 0.001). The number of granulocytes in the whole blood of CCI-CL animals was higher at 3 days when compared to CCI-PL (p < 0.022). Surprisingly, the depletion of Mo /Ma did not affect brain edema. However, the depletion of Mo /Ma did result in a significant decrease in microglia (CCI-CL vs. CCI-PL, p < 0.012). In conclusion, an intact Mo /Ma population is required to repair BBB integrity and microglial response following injury.


Assuntos
Barreira Hematoencefálica/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Macrófagos/metabolismo , Monócitos/metabolismo , Animais , Permeabilidade Capilar , Modelos Animais de Doenças , Masculino , Microglia/metabolismo , Ratos Sprague-Dawley
8.
J Neuroinflammation ; 15(1): 84, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29548333

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is a major cause of death and disability. TBI results in a prolonged secondary central neuro-inflammatory response. Previously, we have demonstrated that multiple doses (2 and 24 h after TBI) of multipotent adult progenitor cells (MAPC) delivered intravenously preserve the blood-brain barrier (BBB), improve spatial learning, and decrease activated microglia/macrophages in the dentate gyrus of the hippocampus. In order to determine if there is an optimum treatment window to preserve the BBB, improve cognitive behavior, and attenuate the activated microglia/macrophages, we administered MAPC at various clinically relevant intervals. METHODS: We administered two injections intravenously of MAPC treatment at hours 2 and 24 (2/24), 6 and 24 (6/24), 12 and 36 (12/36), or 36 and 72 (36/72) post cortical contusion injury (CCI) at a concentration of 10 million/kg. For BBB experiments, animals that received MAPC at 2/24, 6/24, and 12/36 were euthanized 72 h post injury. The 36/72 treated group was harvested at 96 h post injury. RESULTS: Administration of MAPC resulted in a significant decrease in BBB permeability when administered at 2/24 h after TBI only. For behavior experiments, animals were harvested post behavior paradigm. There was a significant improvement in spatial learning (120 days post injury) when compared to cortical contusion injury (CCI) in groups when MAPC was administered at or before 24 h. In addition, there was a significant decrease in activated microglia/macrophages in the dentate gyrus of hippocampus of the treated group (2/24) only when compared to CCI. CONCLUSIONS: Intravenous injections of MAPC at or before 24 h after CCI resulted in improvement of the BBB, improved cognitive behavior, and attenuated activated microglia/macrophages in the dentate gyrus.


Assuntos
Lesões Encefálicas Traumáticas/cirurgia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células-Tronco Multipotentes/fisiologia , Animais , Barreira Hematoencefálica/fisiopatologia , Proteínas de Ligação ao Cálcio/metabolismo , Permeabilidade Capilar/fisiologia , Citocinas/metabolismo , Modelos Animais de Doenças , Proteínas do Domínio Duplacortina , Injeções Intraventriculares , Masculino , Aprendizagem em Labirinto , Proteínas dos Microfilamentos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Células-Tronco Multipotentes/transplante , Neuropeptídeos/metabolismo , Ratos , Tempo de Reação , Fatores de Tempo
9.
Stem Cells ; 35(5): 1416-1430, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28233425

RESUMO

Traumatic brain injury (TBI) is soon predicted to become the third leading cause of death and disability worldwide. After the primary injury, a complex set of secondary injuries develops hours and days later with prolonged neuroinflammation playing a key role. TBI and other inflammatory conditions are currently being treated in preclinical and clinical trials by a number of cellular therapies. Mesenchymal stem cells (MSC) are of great interest due to their widespread usage, safety, and relative ease to isolate and culture. However, there has been a wide range in efficacy reported using MSC clinically and in preclinical models, likely due to differences in cell preparations and a significant amount of donor variability. In this study, we seek to find a correlation between in vitro activity and in vivo efficacy. We designed assays to explore the responsiveness of MSC to immunological cues to address the immunomodulatory properties of MSC, one of their primary modes of therapeutic activity in TBI. Our results showed intrinsic differences in the immunomodulatory capacity of MSC preparations from different bone marrow and amniotic fluid donors. This difference mirrored the therapeutic capacity of the MSC in an experimental model of TBI, an effect confirmed using siRNA knockdown of COX2 followed by overexpressing COX2. Among the immunomodulatory factors assessed, the therapeutic benefit correlated with the secretion of prostaglandin E2 (PGE2 ) by MSC prior to treatment, suggesting that measurement of PGE2 could be a very useful potency marker to create an index of predicted efficacy for preparations of MSC to treat TBI. Stem Cells 2017;35:1416-1430.


Assuntos
Lesões Encefálicas Traumáticas/terapia , Dinoprostona/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Líquido Amniótico/citologia , Animais , Encéfalo/patologia , Lesões Encefálicas Traumáticas/patologia , Contagem de Células , Doença Crônica , Constrição Patológica , Ciclo-Oxigenase 2/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Imunomodulação , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Inflamação/patologia , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Permeabilidade , Ratos Sprague-Dawley
10.
J Surg Res ; 190(2): 628-33, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24906578

RESUMO

BACKGROUND: Blood brain barrier (BBB) compromise is a key pathophysiological component of secondary traumatic brain injury characterized by edema and neuroinflammation in a previously immune-privileged environment. Current assays for BBB permeability are limited by working size, harsh extraction processes, suboptimal detection via absorbance, and wide excitation fluorescence spectra. In this study, we evaluate the feasibility of Alexa Fluor 680, a far-red dye bioconjugated to dextran, as an alternative assay to improve resolution and sensitivity. METHODS: Alexa Fluor was introduced intravenously on the day of sacrifice to three groups: sham, controlled cortical impact (CCI), and CCI treated with a cell based therapy known to reduce BBB permeability. The brains were sectioned coronally and imaged using an infrared laser scanner to generate intensity plot profiles as well as signal threshold images to distinguish regions with varying degrees of permeability. RESULTS: Linear plot profile analysis demonstrated greater signal intensity from CCI than treated rats at corresponding injury depths. Threshold analysis identified rims of signal at low + narrow threshold ranges. The integrated signals from a treatment group known to preserve the BBB were significantly less than the groups with CCI injury alone. There was no significant difference at high + wide signal intensity threshold ranges. CONCLUSIONS: Alexa Fluor 680 infrared photodetection and image analysis can aid in detecting differential degrees of BBB permeability after traumatic brain injury and maybe particularly useful in demonstrating BBB preservation of at-risk regions in response to therapeutic agents.


Assuntos
Barreira Hematoencefálica , Lesões Encefálicas/fisiopatologia , Permeabilidade Capilar , Dextranos , Corantes Fluorescentes , Animais , Lesões Encefálicas/terapia , Circulação Cerebrovascular/fisiologia , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Ratos
11.
Int J Palliat Nurs ; 29(1): 34-42, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36692478

RESUMO

BACKGROUND: The rising prevalence of life-limiting conditions in children and young people warrants an evaluation of paediatric palliative care, hospice services and delivered care. AIM: First, this study aimed to develop a deeper understanding of how extended viewing is experienced by the parents of a deceased child (or young person) with a life-limiting condition, based in Australia. Second, this study aimed to evaluate the quality of bereavement care delivered during the first few days after death. FINDINGS: A total of 17 bereaved parents of 13 children completed an interview. In-depth interviews were audio-recorded, transcribed verbatim and thematically analysed. While the authors acknowledge the complexity and individual nature of grief, four broad themes were identified, namely the importance of the 'physical environment' being conducive to spending time with their child; 'seeing their child'; 'time to say goodbye'; and 'supportive care'. CONCLUSION: The findings of this study reinforce that extended viewing can provide therapeutic benefits for parents, as well as the importance of a skilled palliative care nursing workforce in assisting with grief management.


Assuntos
Luto , Cuidados Paliativos na Terminalidade da Vida , Pais , Adolescente , Criança , Humanos , Pesar , Hospitais para Doentes Terminais , Pais/psicologia
12.
J Neuroinflammation ; 9: 228, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23020860

RESUMO

INTRODUCTION: We have demonstrated previously that the intravenous delivery of multipotent adult progenitor cells (MAPC) after traumatic brain injury affords neuroprotection via interaction with splenocytes, leading to an increase in systemic anti-inflammatory cytokines. We hypothesize that the observed modulation of the systemic inflammatory milieu is related to T regulatory cells and a subsequent increase in the locoregional neuroprotective M2 macrophage population. METHODS: C57B6 mice were injected with intravenous MAPC 2 and 24 hours after controlled cortical impact injury. Animals were euthanized 24, 48, 72, and 120 hours after injury. In vivo, the proportion of CD4(+)/CD25(+)/FOXP3(+) T-regulatory cells were measured in the splenocyte population and plasma. In addition, the brain CD86(+) M1 and CD206(+) M2 macrophage populations were quantified. A series of in vitro co-cultures were completed to investigate the need for direct MAPC:splenocyte contact as well as the effect of MAPC therapy on M1 and M2 macrophage subtype apoptosis and proliferation. RESULTS: Significant increases in the splenocyte and plasma T regulatory cell populations were observed with MAPC therapy at 24 and 48 hours, respectively. In addition, MAPC therapy was associated with an increase in the brain M2/M1 macrophage ratio at 24, 48 and 120 hours after cortical injury. In vitro cultures of activated microglia with supernatant derived from MAPC:splenocyte co-cultures also demonstrated an increase in the M2/M1 ratio. The observed changes were secondary to an increase in M1 macrophage apoptosis. CONCLUSIONS: The data show that the intravenous delivery of MAPC after cortical injury results in increases in T regulatory cells in splenocytes and plasma with a concordant increase in the locoregional M2/M1 macrophage ratio. Direct contact between the MAPC and splenocytes is required to modulate activated microglia, adding further evidence to the central role of the spleen in MAPC-mediated neuroprotection.


Assuntos
Células-Tronco Adultas/transplante , Lesões Encefálicas/patologia , Lesões Encefálicas/terapia , Microglia/fisiologia , Células-Tronco Multipotentes/fisiologia , Administração Intravenosa , Células-Tronco Adultas/fisiologia , Análise de Variância , Animais , Antígenos CD/metabolismo , Barreira Hematoencefálica/fisiopatologia , Comunicação Celular/fisiologia , Proliferação de Células , Terapia Baseada em Transplante de Células e Tecidos , Células Cultivadas , Técnicas de Cocultura , Modelos Animais de Doenças , Citometria de Fluxo , Fatores de Transcrição Forkhead/metabolismo , Humanos , Fígado/citologia , Linfócitos/metabolismo , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Multipotentes/transplante
14.
J Exp Med ; 200(11): 1383-93, 2004 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-15583012

RESUMO

Rapid clearance of pathogens is essential for successful control of pyogenic bacterial infection. Previous experiments have shown that antibody to specific intracellular adhesion molecule-grabbing nonintegrin (SIGN)-R1 inhibits uptake of capsular polysaccharide by marginal zone macrophages, suggesting a role for SIGN-R1 in this process. We now demonstrate that mice lacking SIGN-R1 (a mouse homologue of human dendritic cell-SIGN receptor) are significantly more susceptible to Streptococcus pneumoniae infection and fail to clear S. pneumoniae from the circulation. Marginal zone and peritoneal macrophages show impaired bacterial recognition associated with an inability to bind T-independent type 2 antigens such as dextran. Our work represents the first evidence for a protective in vivo role for a SIGN family molecule.


Assuntos
Antígenos CD/fisiologia , Lectinas Tipo C/fisiologia , Infecções Pneumocócicas/imunologia , Animais , Anticorpos Antibacterianos/sangue , Antígenos CD/genética , Moléculas de Adesão Celular , Clonagem Molecular , Dextranos/metabolismo , Feminino , Imunidade Inata , Lectinas Tipo C/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Células NIH 3T3 , Receptores de Superfície Celular , Streptococcus pneumoniae/imunologia
16.
Sci Rep ; 4: 4565, 2014 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-24691433

RESUMO

Advances in the field of Multipotent Mesenchymal Stromal cell (MSC) biology have demonstrated that MSCs can improve disease outcome when 'activated' to exert immunomodulatory effects. However, the precise mechanisms modulating MSC-immune cells interactions remain largely elusive. In here, we activated MSC based on a recent polarization paradigm, in which MSCs can be polarized towards a pro- or anti-inflammatory phenotype depending on the Toll-like receptor stimulated, to dissect the mechanisms through which MSCs physically interact with and modulate leukocytes in this context. Our data show that MSCs activated through the Toll-like receptor (TLR) 4 pathway increased VCAM-1 and ICAM-1 dependent binding of leukocytes. On the other hand, TLR3 stimulation strongly increases leukocytes affinity to MSC comparatively, through the formation of cable-like hyaluronic acid structures. In addition, TLR4 activation elicited secretion of pro-inflammatory mediators by MSCs, whereas TLR3-activated MSCs displayed a milder pro-inflammatory phenotype, similar to inactivated MSCs. However, the differently activated MSCs maintained their ability to suppress leukocyte activation at similar levels in our in vitro model, and this immunomodulatory property was shown here to be partially mediated by prostaglandin. These results reinforce the concept that alternate activation profiles control MSC responses and may impact the therapeutic use of MSCs.


Assuntos
Comunicação Celular/fisiologia , Diferenciação Celular/fisiologia , Leucócitos Mononucleares/fisiologia , Células-Tronco Mesenquimais/fisiologia , Células Cultivadas , Humanos , Inflamação/metabolismo , Inflamação/patologia , Molécula 1 de Adesão Intercelular/metabolismo , Leucócitos Mononucleares/metabolismo , Células-Tronco Mesenquimais/metabolismo , Receptor 3 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
17.
J Neurosci Methods ; 219(1): 176-82, 2013 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-23928152

RESUMO

BACKGROUND: The inflammatory response after a CNS injury is regulated by microglia/macrophages. Changes in the ratio of M1 classically activated pro-inflammatory cells versus M2 alternatively activated anti-inflammatory cells reveal the direction of the immune response. These cells are routinely identified and enumerated by morphology and cell-surface markers using immunohistochemistry. NEW METHOD: We used a controlled cortical impact (CCI) mouse model for traumatic brain injury (TBI), then isolated microglia/macrophages from neural cell suspensions using magnetic beads conjugated to CD11b monoclonal antibody to obtain the entire myeloid population. Polarization states of CD11b(+)CD45(lo) microglia were evaluated by expression of M1 surface marker FcγRII/III and M2 surface marker CD206. RESULTS: After TBI, we observed an increase in M1:M2 ratio in the ipsilateral hemisphere when compared to the contralateral side, indicating that 24h after CCI, a shift in microglia polarization occurs localized to the hemisphere of injury. Comparison with existing method(s): The major impetus for developing and refining the methods was the need to accurately quantify microglial activation states without reliance on manual morphometric counting of serial immunohistochemistry slides. Flow cytometric analysis of enriched cell suspensions provides quantitative measurement of microglial polarization states complementary to existing methods, but for entire populations of cells. CONCLUSIONS: In summary, we used immunomagnetic beads to isolate myeloid cells from injured brain, then stained surface antigens to flow cytometrically identify and categorize microglia as either classically activated M1 or alternatively activated M2, generating a ratio of M1:M2 cells which is useful in studying attempts to reduce or redirect neuroinflammation.


Assuntos
Citometria de Fluxo/métodos , Separação Imunomagnética/métodos , Microglia/fisiologia , Animais , Encéfalo/patologia , Lesões Encefálicas/patologia , Antígeno CD11b/análise , Separação Celular , Interpretação Estatística de Dados , Corantes Fluorescentes , Imuno-Histoquímica , Antígenos Comuns de Leucócito/análise , Contagem de Leucócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
18.
Stem Cells Transl Med ; 2(12): 953-60, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24191266

RESUMO

We previously demonstrated that the intravenous delivery of multipotent adult progenitor cells (MAPCs) after traumatic brain injury (TBI) in rodents provides neuroprotection by preserving the blood-brain barrier and systemically attenuating inflammation in the acute time frame following cell treatment; however, the long-term behavioral and anti-inflammatory effects of MAPC administration after TBI have yet to be explored. We hypothesized that the intravenous injection of MAPCs after TBI attenuates the inflammatory response (as measured by microglial morphology) and improves performance at motor tasks and spatial learning (Morris water maze [MWM]). MAPCs were administered intravenously 2 and 24 hours after a cortical contusion injury (CCI). We tested four groups at 120 days after TBI: sham (uninjured), injured but not treated (CCI), and injured and treated with one of two concentrations of MAPCs, either 2 million cells per kilogram (CCI-2) or 10 million cells per kilogram (CCI-10). CCI-10 rats showed significant improvement in left hind limb deficit on the balance beam. On the fifth day of MWM trials, CCI-10 animals showed a significant decrease in both latency to platform and distance traveled compared with CCI. Probe trials revealed a significant decrease in proximity measure in CCI-10 compared with CCI, suggesting improved memory retrieval. Neuroinflammation was quantified by enumerating activated microglia in the ipsilateral hippocampus. We observed a significant decrease in the number of activated microglia in the dentate gyrus in CCI-10 compared with CCI. Our results demonstrate that intravenous MAPC treatment after TBI in a rodent model offers long-term improvements in spatial learning as well as attenuation of neuroinflammation.


Assuntos
Células-Tronco Adultas/transplante , Comportamento Animal , Lesões Encefálicas/cirurgia , Encéfalo/patologia , Ativação de Macrófagos , Macrófagos/patologia , Aprendizagem em Labirinto , Microglia/patologia , Células-Tronco Multipotentes/transplante , Comportamento Espacial , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/psicologia , Modelos Animais de Doenças , Encefalite/patologia , Encefalite/fisiopatologia , Encefalite/cirurgia , Injeções Intravenosas , Macrófagos/metabolismo , Masculino , Microglia/metabolismo , Atividade Motora , Ratos , Tempo de Reação , Recuperação de Função Fisiológica , Fatores de Tempo
19.
J Trauma Acute Care Surg ; 75(3): 410-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23928737

RESUMO

BACKGROUND: Autologous bone marrow-derived mononuclear cells (AMNCs) have shown therapeutic promise for central nervous system insults such as stroke and traumatic brain injury (TBI). We hypothesized that intravenous injection of AMNC provides neuroprotection, which leads to cognitive improvement after TBI. METHODS: A controlled cortical impact (CCI) rodent TBI model was used to examine blood-brain barrier (BBB) permeability, neuronal and glial apoptosis, as well as cognitive behavior. Two groups of rats underwent CCI with AMNC treatment (CCI-autologous) or without AMNC treatment (CCI-alone), consisting of 2 million AMNC per kilogram body weight harvested from the tibia and intravenously injected 72 hours after injury. CCI-alone animals underwent sham harvests and received vehicle injections. RESULTS: Ninety-six hours after injury, AMNC significantly reduced the BBB permeability in injured animals, and there was an increase in apoptosis of proinflammatory activated microglia in the ipsilateral hippocampus. At 4 weeks after injury, we observed significant improvement in probe testing of CCI-Autologous group in comparison to CCI-Alone in the Morris Water Maze paradigm. CONCLUSION: Our data demonstrate that the intravenous injection of AMNC after TBI leads to neuroprotection by preserving early BBB integrity, increasing activated microglial apoptosis and improving cognitive function.


Assuntos
Transplante de Medula Óssea/métodos , Lesões Encefálicas/cirurgia , Leucócitos Mononucleares/transplante , Macrófagos/fisiologia , Aprendizagem em Labirinto/fisiologia , Microglia/fisiologia , Animais , Apoptose/fisiologia , Barreira Hematoencefálica/fisiopatologia , Lesões Encefálicas/complicações , Lesões Encefálicas/fisiopatologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/prevenção & controle , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley
20.
Cell ; 124(2): 301-13, 2006 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-16439205

RESUMO

DNA nonhomologous end-joining (NHEJ) is a predominant pathway of DNA double-strand break repair in mammalian cells, and defects in it cause radiosensitivity at the cellular and whole-organism levels. Central to NHEJ is the protein complex containing DNA Ligase IV and XRCC4. By searching for additional XRCC4-interacting factors, we identified a previously uncharacterized 33 kDa protein, XRCC4-like factor (XLF, also named Cernunnos), that has weak sequence homology with XRCC4 and is predicted to display structural similarity to XRCC4. We show that XLF directly interacts with the XRCC4-Ligase IV complex in vitro and in vivo and that siRNA-mediated downregulation of XLF in human cell lines leads to radiosensitivity and impaired NHEJ. Furthermore, we establish that NHEJ-deficient 2BN cells derived from a radiosensitive and immune-deficient patient lack XLF due to an inactivating frameshift mutation in its gene, and that reintroduction of wild-type XLF into such cells corrects their radiosensitivity and NHEJ defects. XLF thus constitutes a novel core component of the mammalian NHEJ apparatus.


Assuntos
DNA Ligases/metabolismo , Reparo do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Sequência Consenso , DNA Ligase Dependente de ATP , Enzimas Reparadoras do DNA , Regulação para Baixo , Humanos , Dados de Sequência Molecular , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Tolerância a Radiação , Alinhamento de Sequência
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