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1.
Signal Transduct Target Ther ; 8(1): 305, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37591843

RESUMO

Although VEGF-B was discovered as a VEGF-A homolog a long time ago, the angiogenic effect of VEGF-B remains poorly understood with limited and diverse findings from different groups. Notwithstanding, drugs that inhibit VEGF-B together with other VEGF family members are being used to treat patients with various neovascular diseases. It is therefore critical to have a better understanding of the angiogenic effect of VEGF-B and the underlying mechanisms. Using comprehensive in vitro and in vivo methods and models, we reveal here for the first time an unexpected and surprising function of VEGF-B as an endogenous inhibitor of angiogenesis by inhibiting the FGF2/FGFR1 pathway when the latter is abundantly expressed. Mechanistically, we unveil that VEGF-B binds to FGFR1, induces FGFR1/VEGFR1 complex formation, and suppresses FGF2-induced Erk activation, and inhibits FGF2-driven angiogenesis and tumor growth. Our work uncovers a previously unrecognized novel function of VEGF-B in tethering the FGF2/FGFR1 pathway. Given the anti-angiogenic nature of VEGF-B under conditions of high FGF2/FGFR1 levels, caution is warranted when modulating VEGF-B activity to treat neovascular diseases.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Fator B de Crescimento do Endotélio Vascular , Humanos , Fator 2 de Crescimento de Fibroblastos/genética , Imunoterapia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética
2.
J Natl Cancer Inst ; 115(10): 1145-1156, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37352403

RESUMO

The recent expansion of human genomics repositories has facilitated the discovery of novel TP53 variants in populations of different ethnic origins. Interpreting TP53 variants is a major clinical challenge because they are functionally diverse, confer highly variable predisposition to cancer (including elusive low-penetrance alleles), and interact with genetic modifiers that alter tumor susceptibility. Here, we discuss how a cancer risk continuum may relate to germline TP53 mutations on the basis of our current review of genotype-phenotype studies and an integrative analysis combining functional and sequencing datasets. Our study reveals that each ancestry contains a distinct TP53 variant landscape defined by enriched ethnic-specific alleles. In particular, the discovery and characterization of suspected low-penetrance ethnic-specific variants with unique functional consequences, including P47S (African), G334R (Ashkenazi Jewish), and rs78378222 (Icelandic), may provide new insights in terms of managing cancer risk and the efficacy of therapy. Additionally, our analysis highlights infrequent variants linked to milder cancer phenotypes in various published reports that may be underdiagnosed and require further investigation, including D49H in East Asians and R181H in Europeans. Overall, the sequencing and projected functions of TP53 variants arising within ethnic populations and their interplay with modifiers, as well as the emergence of CRISPR screens and AI tools, are now rapidly improving our understanding of the cancer susceptibility spectrum, leading toward more accurate and personalized cancer risk assessments.


Assuntos
Neoplasias , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/genética , Predisposição Genética para Doença , Neoplasias/genética , Mutação em Linhagem Germinativa , Células Germinativas
3.
Sci Rep ; 13(1): 4609, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36944702

RESUMO

PVR (poliovirus receptor) functions as a ligand that signals through TIGIT and CD96 to induce suppression of T-cell and NK-cell responses. Alternatively, PVR binds to CD226, resulting in a co-stimulatory signal. To date, TIGIT antibody antagonists have been developed to restore immune functions and allow PVR to signal though CD226 in the context of cancer immunotherapy. Due to PVR receptor heterogeneity, agonizing either of these pathways with a recombinant form of the PVR extracellular domain represents a therapeutic strategy for either immunosuppression or activation. Here, we developed a minimal murine PVR-Fc fusion construct, consisting of only the IgV domain of PVR (vdPVR-Fc), and assessed its ability to dampen inflammatory responses in a murine model of psoriasis. vdPVR-Fc and PVR-Fc containing the full-length extracellular domain bound to TIGIT, CD96 and CD226 with similar low nanomolar affinities as defined by surface plasmon resonance. vdPVR-Fc was also able to suppress the in-vitro proliferation of murine CD4+ and CD8+ T-cells in mixed splenocyte cultures. Importantly, vdPVR-Fc delayed the onset, and reduced inflammatory responses (scaling and thickness) in a murine model of psoriasis. Collectively, our results suggest that the minimal IgV domain of PVR is sufficient to dampen immune responses in-vitro and attenuate symptoms of psoriasis in-vivo.


Assuntos
Linfócitos T CD8-Positivos , Receptores Virais , Animais , Camundongos , Antígenos CD/metabolismo , Modelos Animais de Doenças , Receptores Imunológicos/metabolismo , Receptores Virais/metabolismo , Tolerância Imunológica , Psoríase/imunologia
4.
Cell Immunol ; 379: 104581, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35933919

RESUMO

VISTA has been proposed to function both as a ligand and a receptor to dampen immune responses, although the role of VISTA as a ligand on myeloid cells has been largely ignored. We observed that a VISTA receptor is rapidly expressed on the surface of macrophages and neutrophils upon exposure to lipopolysaccharides (LPS). Importantly, treating LPS-stimulated macrophages and neutrophils ex vivo with a high-avidity agonist of the VISTA receptor (VISTA.COMP) results in the downregulation of pro-inflammatory cytokines and the increased expression of immunoregulatory genes. Finally, the in vivo administration of VISTA.COMP attenuated the rise in circulating TNFα, IL-6, and IL-12p40 in LPS-treated mice.


Assuntos
Lipopolissacarídeos , Neutrófilos , Animais , Citocinas/metabolismo , Inflamação , Ligantes , Lipopolissacarídeos/metabolismo , Macrófagos , Proteínas de Membrana , Camundongos
5.
Front Immunol ; 13: 836837, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35359946

RESUMO

Post-traumatic knee osteoarthritis is characterized by cartilage degeneration, subchondral bone remodeling, osteophyte formation, and synovial changes. Therapeutic targeting of inflammatory activity in the knee immediately post injury may alter the course of osteoarthritis development. This study aimed to determine whether CD200R1 agonists, namely the protein therapeutic CD200Fc or the synthetic DNA aptamer CCS13, both known to act as anti-inflammatory agents, are able to delay the pathogenesis of injury-associated knee osteoarthritis in a murine model. Ten week old male C57BL/6 mice were randomized and surgical destabilization of the medial meniscus (DMM) to induce knee arthritis or sham surgery as a control were performed. CCS13 was evaluated as a therapeutic treatment along with CD200Fc and a phosphate-buffered saline vehicle control. Oligonucleotides were injected intra-articularly beginning one week after surgery, with a total of six injections administered prior to sacrifice at 12 weeks post-surgery. Histopathological assessment was used as the primary outcome measure to assess cartilage and synovial changes, while µCT imaging was used to compare the changes to the subchondral bone between untreated and treated arthritic groups. We did not find any attenuation of cartilage degeneration or synovitis in DMM mice with CD200Fc or CCS13 at 12 weeks post-surgery, nor stereological differences in the properties of subchondral bone. The use of CD200R1 agonists to blunt the inflammatory response in the knee are insufficient to prevent disease progression in the mouse DMM model of OA without anatomical restoration of the normal joint biomechanics.


Assuntos
Osteoartrite do Joelho , Sinovite , Animais , Modelos Animais de Doenças , Articulação do Joelho/patologia , Masculino , Meniscos Tibiais/patologia , Meniscos Tibiais/cirurgia , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Orexina , Osteoartrite do Joelho/tratamento farmacológico , Osteoartrite do Joelho/etiologia , Sinovite/patologia
6.
J Neurosurg ; : 1-7, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35078154

RESUMO

OBJECTIVE: Approximately 10% of patients with mild traumatic brain injury (mTBI) have intracranial bleeding (complicated mTBI) and 3.5% eventually require neurosurgical intervention, which is mostly available at centers with a higher level of trauma care designation and often requires interhospital transfer. In 2018, the Brain Injury Guidelines (BIG) were updated in the United States to guide emergency department care and patient disposition for complicated mild to moderate TBI. The aim of this study was to validate the sensitivity and specificity of the updated BIG (uBIG) for predicting the need for interhospital transfer in Canadian patients with complicated mTBI. METHODS: This study took place at three level I trauma centers. Consecutive medical records of patients with complicated mTBI (Glasgow Coma Scale score 13-15) who were aged ≥ 16 years and presented between September 2016 and December 2017 were retrospectively reviewed. Patients with a penetrating trauma and those who had a documented cerebral tumor or aneurysm were excluded. The primary outcome was a combination of neurosurgical intervention and/or mTBI-related death. Sensitivity and specificity analyses were performed. RESULTS: A total of 477 patients were included, of whom 8.4% received neurosurgical intervention and 3% died as a result of their mTBI. Forty patients (8%) were classified as uBIG-1, 168 (35%) as uBIG-2, and 269 (56%) as uBIG-3. No patients in uBIG-1 underwent neurosurgical intervention or died as a result of their injury. This translates into a sensitivity for predicting the need for a transfer of 100% (95% CI 93.2%-100%) and a specificity of 9.4% (95% CI 6.8%-12.6%). Using the uBIG could potentially reduce the number of transfers by 6% to 25%. CONCLUSIONS: The patients in uBIG-1 could be safely managed at their initial center without the need for transfer to a center with a higher level of neurotrauma care. Although the uBIG could decrease the number of transfers, further refinement of the criteria could improve its specificity.

7.
ACS Pharmacol Transl Sci ; 5(2): 62-69, 2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36742360

RESUMO

BirA*, a mutant form of the biotinylating enzyme BirA, can nonspecifically biotinylate ε-amino groups on lysines of proteins. Based on the promiscuous labeling nature of BirA*, plasmids expressing fusion constructs of BirA* to a given ligand have been used to transfect eukaryotic cells, leading to the biotinylation of intracellular proteins interacting or in close proximity to such Ligand.BirA* constructs. Mass spectrometry performed on the recovered biotinylated partners allows one to map intracellular protein interactors, a technique known as BioID. In contrast, the expression and purification of recombinant Ligand.BirA* constructs could serve as a powerful tool for labeling and detecting cell surface receptors. Here, we report the design and expression of recombinant Affibody.BirA* constructs, ZEGFR:1907.BirA* and ZHER2:243.BirA*, as protein bispecifics able to biotinylate their respective receptors EGFR and HER2 on the surface of MDA-MB-231 (EGFR+, EpCaM+, and CD44+) and SK-OV-3 (HER2++, EGFR+, EpCaM+, and CD44+) cancer cells. These Affibody.BirA* constructs retain both their BirA* enzymatic activity as well as their receptor-binding function. Importantly, MDA-MB-231 and SK-OV-3 cells biotinylated with Affibody.BirA* constructs did label their receptors EGFR and HER2 but did not biotinylate irrelevant antigens such as EpCaM or CD44 present on the surface of both cell lines. Ligand.BirA* bispecifics may represent a promising class of agents to identify unknown receptors on cell surfaces.

8.
MAbs ; 13(1): 2003281, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34818120

RESUMO

The V-domain Ig Suppressor of T-cell Activation (VISTA) is an immune checkpoint regulator that suppresses immune responses and is readily expressed on human and murine myeloid cells and T cells. This immunosuppressive pathway can be activated using VISTA agonists. Here, we report the development of murine anti-human VISTA (anti-hVISTA) monoclonal antibodies (mAbs), anti-hVISTA nanobodies (Nbs), and cross-reactive rat anti-murine/human VISTA (anti-hmVISTA) mAbs. All mAbs and Nbs generated bound to VISTA (human and/or murine) with dissociation constants in the sub-nanomolar or low nanomolar range. Competition analysis revealed that the selected Nbs bound the same or a nearby epitope(s) as the human VISTA-specific mAbs. However, the cross-reactive mAbs only partially competed with Nbs for binding to hVISTA. All mAbs and one Nb (hVISTANb7) were able to strongly detect VISTA expression on primary human monocytes. Importantly, the murine anti-hVISTA mAbs 7E12 and 7G5 displayed strong agonistic activity in human peripheral blood mononuclear cell cultures, while Nb7 and rat anti-hmVISTA mAbs 3C3, 7C6, 7C7, and 7G1 also behaved as hVISTA agonists, albeit to a lesser extent. Cross-reactive mAbs 7C7 and 7G1 further displayed agonistic potential in murine splenocyte assays. Importantly, mAb 7G1 significantly reduced inflammation associated with the murine model of imiquimod-induced psoriasis. These agonistic VISTA mAbs may represent therapeutic leads to treat inflammatory disorders.


Assuntos
Anticorpos de Domínio Único , Animais , Anticorpos Monoclonais , Humanos , Leucócitos Mononucleares , Ativação Linfocitária , Camundongos , Ratos , Linfócitos T
9.
Brain Inj ; 35(10): 1267-1274, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34488497

RESUMO

OBJECTIVES: To determine the predicting demographic, clinical and radiological factors for neurosurgical intervention in complicated mild traumatic brain injury (mTBI) patients. METHODS: Design: retrospective multicenter cohort study. Participants: patients aged ≥16 presenting to all level-I trauma centers in Quebec between 09/2016 and 12/2017 with mTBI(GCS 13-15) and complication on initial head CT (intracranial hemorrhage/skull fracture). Procedure: Consecutive medical records were reviewed and separated into two groups: no neurosurgical intervention and neurosurgical intervention (NSI). Main outcome: neurosurgical intervention. Analysis: multiple logistic regression model. RESULTS: Four hundred and seventy-eight patients were included and 40 underwent NSI. One patient had radiological deterioration but no clinical deterioration prior to surgery. Subdural hemorrhage ≥4 mm width (OR:3.755 [95% CI:1.290-10.928]) and midline shift (OR:7.507 [95% CI: 3.317-16.989]) increased the risk of NSI. Subarachnoid hemorrhage was associated with a lower risk of NSI (OR:0.312 [95% CI: 0.136-0.713]). All other intracranial hemorrhages were not associated with NSI. CONCLUSION: Radiological deterioration was not associated with the incidence of NSI. Subdural hemorrhage and midline shift should be predicting factors for neurosurgery. Some patients with isolated findings such as subarachnoid hemorrhage could be safely managed in their original center without being transferred to a level-I trauma center.


Assuntos
Concussão Encefálica , Concussão Encefálica/complicações , Concussão Encefálica/diagnóstico por imagem , Concussão Encefálica/cirurgia , Estudos de Coortes , Escala de Coma de Glasgow , Hematoma Subdural/diagnóstico por imagem , Hematoma Subdural/cirurgia , Humanos , Estudos Retrospectivos
10.
JCI Insight ; 5(22)2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33208551

RESUMO

Adoptive cell therapy involves the infusion of tumor-reactive T cells into patients with cancer to provide antitumor immunity. The ex vivo expansion and differentiation of such T cells are key parameters that affect their therapeutic potential. Human T cells are presently expanded in culture through the use of anti-CD3 and anti-CD28 mAbs immobilized on beads, expressed on cells, or assembled in the context of soluble antibody complexes. Here we report the design of a small, bispecific single-chain variable fragment construct agonizing both CD3 and CD28 pathways. This soluble T cell expansion protein, termed T-CEP, activates, expands, and differentiates human T cells ex vivo at concentrations in the femtomolar range. Importantly, T-CEP promotes the preferential growth of human CD8+ T cells over the course of 12 days in comparison with methods involving immobilized anti-CD3 mAb/soluble anti-CD28 mAb or soluble anti-CD3/CD28 mAb complexes. The differentiation profile of the resulting human T cell population is also singularly affected by T-CEP, favoring the expansion of a preferred CD8+CD27+ T cell phenotype. The activity profile of T-CEP on human T cells ex vivo suggests its use in generating human T cell populations that are more suited for adoptive cell therapy.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos CD28/imunologia , Complexo CD3/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Ativação Linfocitária/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Anticorpos Monoclonais/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Humanos , Imunoterapia Adotiva , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
11.
Sci Rep ; 10(1): 19104, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33127968

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

12.
Cancers (Basel) ; 12(8)2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32722340

RESUMO

Loss of p53 promotes vascular endothelial growth factor (VEGF)-A up-regulation and the angiogenic potential of cancer cells. We investigated TP53 somatic mutations in 110 primary gastric adenocarcinomas of two retrospective metastatic series including 48 patients treated with second-line Ramucirumab/Paclitaxel and 62 patients who received first-line chemotherapy with Cisplatin or Oxaliplatin plus 5-Fluorouracil. Missense mutations were classified by tumor protein p53 (TP53) mutant-specific residual transcriptional activity scores (TP53RTAS) and used to stratify patients into two groups: transcriptionally TP53Active and TP53Inactive. The primary endpoint was overall survival (OS). An additional analysis was addressed to measure VEGF/VEGF receptor 2 (VEGFR2) expression levels in relation to the TP53RTAS. In the Ramucirumab/Paclitaxel group, 29/48 (60.4%) patients had TP53 mutations. Ten patients with TP53Inactive mutations showed better OS than carriers of other TP53 mutations. This effect was retained in the multivariate model analysis (Hazard Ratio = 0.29, 95% confidence interval = 0.17-0.85, p = 0.02). In the chemotherapy group, 41/62 (66%) patients had TP53 mutations, and the 11 carriers of TP53Inactive mutations showed the worst OS (Hazard Ratio = 2.64, 95% confidence interval = 1.17-5.95, p = 0.02). VEGF-A mRNA expression levels were significantly increased in TP53Inactive cases. Further studies are warranted to explore the effect of TP53Inactive mutations in different anti-cancer regimens. This information would lead to new tailored therapy strategies for this lethal disease.

13.
Sci Rep ; 10(1): 2802, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32071325

RESUMO

Protein-based nanobubbles such as halophilic archaeabacterial gas vesicles (GVs) represent a new class of stable, homogeneous nanoparticles with acoustic properties that allow them to be visualized by ultrasound (US) waves. To design GVs as theranostic agents, we modified them to respond to light, with a view to locally generate reactive oxygen species that can kill cancer cells. Specifically, up to 60,000 photoreactive chlorin e6 (Ce6) molecules were chemically attached to lysine ε-amino groups present on the surface of each purified Halobacterium sp. NRC-1 GV. The resulting fluorescent NRC-1 Ce6-GVs have dimensions comparable to that of native GVs and were efficiently taken up by human breast [MCF-7] and human hypopharyngeal [FaDu-GFP] cancer cells as monitored by confocal microscopy and flow cytometry. When exposed to light, internalized Ce6-GVs were 200-fold more effective on a molar basis than free Ce6 at killing cells. These results demonstrate the potential of Ce6-GVs as novel and promising nanomaterials for image-guided photodynamic therapy.


Assuntos
Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Porfirinas/uso terapêutico , Radiossensibilizantes/uso terapêutico , Nanomedicina Teranóstica , Clorofilídeos , Humanos , Células MCF-7 , Fotoquimioterapia , Espécies Reativas de Oxigênio/metabolismo
14.
Biofabrication ; 12(2): 025002, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015225

RESUMO

The current standard of care for patients with severe large-area burns consists of autologous skin grafting or acellular dermal substitutes. While emerging options to accelerate wound healing involve treatment with allogeneic or autologous cells, delivering cells to clinically relevant wound topologies, orientations, and sizes remains a challenge. Here, we report the one-step in situ formation of cell-containing biomaterial sheets using a handheld instrument that accommodates the topography of the wound. In an approach that maintained cell viability and proliferation, we demonstrated conformal delivery to surfaces that were inclined up to 45° with respect to the horizontal. In porcine pre-clinical models of full-thickness burn, we delivered mesenchymal stem/stromal cell-containing fibrin sheets directly to the wound bed, improving re-epithelialization, dermal cell repopulation, and neovascularization, indicating that this device could be introduced in a clinical setting improving dermal and epidermal regeneration.


Assuntos
Queimaduras/fisiopatologia , Queimaduras/terapia , Pele Artificial , Pele/fisiopatologia , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Queimaduras/metabolismo , Diferenciação Celular , Proliferação de Células , Fibrina/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Pele/química , Pele/lesões , Pele/metabolismo , Transplante de Pele , Suínos , Cicatrização
15.
Matrix Biol ; 88: 19-32, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31756413

RESUMO

We report here that Glypican-6 (GPC6)-null mice display at birth small intestines that are 75% shorter than those of normal littermates. Notably, we demonstrate that the role of GPC6 in intestinal elongation is mediated by both Hedgehog (Hh) and non-canonical Wnt signaling. Based on results from in vitro experiments, we had previously proposed that GPC6 stimulates Hh signaling by interacting with Hh and Patched1 (Ptc1), and facilitating/stabilizing their interaction. Here we provide strong support to this hypothesis by showing that GPC6 binds to Ptc1 in the mesenchymal layer of embryonic intestines. This study also provides experimental evidence that strongly suggests that GPC6 inhibits the activity of Wnt5a on the intestinal epithelium by binding to this growth factor, and reducing its release from the surrounding mesenchymal cells. Finally, we show that whereas the mesenchymal layer of GPC6-null intestines displays reduced cell proliferation and a thinner smooth muscle layer, epithelial cell differentiation is not altered in the mutant gut.


Assuntos
Glipicanas/genética , Glipicanas/metabolismo , Intestinos/crescimento & desenvolvimento , Receptor Patched-1/metabolismo , Proteína Wnt-5a/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Células HEK293 , Proteínas Hedgehog/metabolismo , Humanos , Intestinos/citologia , Camundongos , Células NIH 3T3 , Via de Sinalização Wnt
16.
Cancer Immunol Immunother ; 69(1): 103-114, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31811336

RESUMO

We previously reported that CD200 overexpression in the host decreases progression and metastasis of the highly aggressive metastatic 4THM breast carcinoma. We have explored a possible synergistic interaction between the CD200 mimetic PEG-M49 and pegylated liposomal doxorubicin (Peg-Dox) in wild-type CD200 knockout (CD200-/-) and CD200 Receptor 1 knockout (CD200R1-/-) mice for the first time. A 4THM breast carcinoma model and three groups of BALB/c mice (wild type, CD200-/- and CD200R1-/-) were used. Five days after injection of tumor cells, mice were injected with Peg-Dox (ip, once a week) and PEG-M49 or a control aptamer (iv, every 3 days). Necropsies were performed either 12 (mid-point) or 24 (endpoint) days after injection and the extent of tumor growth, visceral metastasis and changes in the tumor-directed immune response were evaluated. PEG-M49 and Peg-Dox co-treatment induced complete tumor regression and loss of macroscopic lung metastasis in four out of seven WT mice. This synergistic anti-tumoral effect is thought to be due to Peg-M49-induced inhibition of Gr1 + CD11b + cells and Peg-Dox-induced increases in tumor-infiltrating CD8 + and CD8CD4 double-positive cells. Similar changes were observed in CD200R1-/- mice indicating that the primary effects of Peg-M49 are mediated by non-CD200R1 receptors. We also demonstrated for the first time that tumor growth, metastasis, and tumor infiltrating GR1 + CD11b + cells were markedly increased in CD200R1-/- mice, indicating an anti-inflammatory and protective role of CD200. CD200 mimetics might be a safe and effective immunomodulatory treatment in conjunction with classical chemotherapeutics for therapy of aggressive metastatic breast carcinoma.


Assuntos
Antígenos CD/genética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Aptâmeros de Nucleotídeos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/análogos & derivados , Animais , Antígenos CD/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Sinergismo Farmacológico , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptores de Orexina/genética , Receptores de Orexina/imunologia , Polietilenoglicóis/farmacologia , Polietilenoglicóis/uso terapêutico
17.
Emerg Med J ; 36(10): 617-619, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31326953

RESUMO

OBJECTIVE: With the ageing population, the prevalence of mild traumatic brain injury (mTBI) among older patients is increasing, and the age criteria of the Canadian CT head rule (CCHR) is challenged by many emergency physicians. We modified the age criteria of the CCHR to evaluate its predictive capacity. METHODS: We conducted a retrospective cohort study at a level 1 trauma centre ED of all mTBI patients 65 years old and over with an mTBI between 2010 and 2014. Main outcome was a clinically important brain injury (CIBI) reported on CT. The clinical and radiological data collection was standardised. Univariate analyses were performed to measure the predictive capacities of different age cut-offs at 70, 75 and 80 years old. RESULTS: 104 confirmed mTBI were included; CT scan identified 32 (30.8%) CIBI. Sensitivity and specificity (95% CI) of the CCHR were 100% (89.1 to 100) and 4.2% (0.9 to 11.7) for a modified criteria of 70 years old; 100% (89.1 to 100) and 13.9% (6.9 to 24.1) for 75 years old; and 90.6% (75.0 to 98.0) and 23.6% (14.4 to 35.1) for 80 years old. Furthermore, modifying the age criteria to 75 years old showed a reduction of CT up to 25% (n=10/41) among the individuals aged 65-74 without missing CIBI. CONCLUSION: Adjusting the age criteria of the Canadian CT head rule to 75 years old could be safe while reducing radiation and ED resources. A future prospective study is suggested to confirm the proposed modification.


Assuntos
Lesões Encefálicas Traumáticas/diagnóstico por imagem , Regras de Decisão Clínica , Hemorragias Intracranianas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/normas , Centros de Traumatologia/normas , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas Traumáticas/complicações , Feminino , Cabeça/diagnóstico por imagem , Cabeça/efeitos da radiação , Humanos , Hemorragias Intracranianas/etiologia , Masculino , Valor Preditivo dos Testes , Quebeque , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/efeitos adversos , Procedimentos Desnecessários/normas
18.
PLoS Comput Biol ; 15(3): e1006895, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30856172

RESUMO

Understanding the principles by which agents interact with both complex environments and each other is a key goal of decision neuroscience. However, most previous studies have used experimental paradigms in which choices are discrete (and few), play is static, and optimal solutions are known. Yet in natural environments, interactions between agents typically involve continuous action spaces, ongoing dynamics, and no known optimal solution. Here, we seek to bridge this divide by using a "penalty shot" task in which pairs of monkeys competed against each other in a competitive, real-time video game. We modeled monkeys' strategies as driven by stochastically evolving goals, onscreen positions that served as set points for a control model that produced observed joystick movements. We fit this goal-based dynamical system model using approximate Bayesian inference methods, using neural networks to parameterize players' goals as a dynamic mixture of Gaussian components. Our model is conceptually simple, constructed of interpretable components, and capable of generating synthetic data that capture the complexity of real player dynamics. We further characterized players' strategies using the number of change points on each trial. We found that this complexity varied more across sessions than within sessions, and that more complex strategies benefited offensive players but not defensive players. Together, our experimental paradigm and model offer a powerful combination of tools for the study of realistic social dynamics in the laboratory setting.


Assuntos
Tomada de Decisões/fisiologia , Objetivos , Modelos Neurológicos , Animais , Biologia Computacional , Macaca mulatta , Masculino , Recompensa , Jogos de Vídeo
19.
Ultrasound Med Biol ; 45(2): 500-512, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30447880

RESUMO

Checkpoint inhibitor (CI) immunotherapy is playing an increasingly prominent role in the treatment of cancer but is effective and durable in only a subset of patients. There are concerted efforts to improve CI therapy through the use of multiple CIs or use of CIs in combination with other anti-cancer agents. Here we investigate the use of "anti-vascular" ultrasound-stimulated microbubble (USMB) treatments in combination with anti-PD-1 CI therapy. The colorectal cancer cell line CT26 was used to conduct longitudinal growth studies along with acute experiments to assess ultrasound-induced anti-tumor immune responses using flow cytometry and enzyme-linked immunospot (ELISPOT) analysis. Longitudinal experiments indicated that USMB + anti-PD-1 treatments significantly enhanced tumor growth inhibition and animal survival relative to monotherapies. Flow cytometry and ELISPOT data did not clearly support a T cell-dependent mechanism for the enhancement. Therefore, the results indicate the ability of anti-vascular USMBs to increase the anti-tumor effects of CI therapy; the specific mechanisms of enhancement remain to be established.


Assuntos
Neoplasias Colorretais/imunologia , Neoplasias Colorretais/terapia , Imunoterapia/métodos , Microbolhas , Ultrassom/métodos , Animais , Linhagem Celular Tumoral , Terapia Combinada/métodos , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos BALB C
20.
Neurology ; 91(18): e1660-e1668, 2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30266886

RESUMO

OBJECTIVE: To determine the safety and efficacy of balloon vs sham venoplasty of narrowing of the extracranial jugular and azygos veins in multiple sclerosis (MS). METHODS: Patients with relapsing or progressive MS were screened using clinical and ultrasound criteria. After confirmation of >50% narrowing by venography, participants were randomized 1:1 to receive balloon or sham venoplasty of all stenoses and were followed for 48 weeks. Participants and research staff were blinded to intervention allocation. The primary safety outcome was the number of adverse events (AEs) during 48 weeks. The primary efficacy outcome was the change from baseline to week 48 in the patient-reported outcome MS Quality of Life-54 (MSQOL-54) questionnaire. Standardized clinical and MRI outcomes were also evaluated. RESULTS: One hundred four participants were randomized (55 sham; 49 venoplasty) and 103 completed 48 weeks of follow-up. Twenty-three sham and 21 venoplasty participants reported at least 1 AE; one sham (2%) and 5 (10%) venoplasty participants had a serious AE. The mean improvement in MSQOL-54 physical score was +1.3 (sham) and +1.4 (venoplasty) (p = 0.95); MSQOL-54 mental score was +1.2 (sham) and -0.8 (venoplasty) (p = 0.55). CONCLUSIONS: Our data do not support the continued use of venoplasty of extracranial jugular and/or azygous venous narrowing to improve patient-reported outcomes, chronic MS symptoms, or the disease course of MS. CLINICALTRIALSGOV IDENTIFIER: NCT01864941. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that for patients with MS, balloon venoplasty of extracranial jugular and azygous veins is not beneficial in improving patient-reported, standardized clinical, or MRI outcomes.


Assuntos
Angioplastia com Balão/métodos , Veia Ázigos/cirurgia , Veias Jugulares/cirurgia , Esclerose Múltipla/terapia , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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