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1.
Cell ; 185(17): 3263-3277.e15, 2022 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-35931082

RESUMEN

Live bacterial therapeutics (LBTs) could reverse diseases by engrafting in the gut and providing persistent beneficial functions in the host. However, attempts to functionally manipulate the gut microbiome of conventionally raised (CR) hosts have been unsuccessful because engineered microbial organisms (i.e., chassis) have difficulty in colonizing the hostile luminal environment. In this proof-of-concept study, we use native bacteria as chassis for transgene delivery to impact CR host physiology. Native Escherichia coli bacteria isolated from the stool cultures of CR mice were modified to express functional genes. The reintroduction of these strains induces perpetual engraftment in the intestine. In addition, engineered native E. coli can induce functional changes that affect physiology of and reverse pathology in CR hosts months after administration. Thus, using native bacteria as chassis to "knock in" specific functions allows mechanistic studies of specific microbial activities in the microbiome of CR hosts and enables LBT with curative intent.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Animales , Bacterias/genética , Escherichia coli/genética , Microbioma Gastrointestinal/fisiología , Ratones , Transgenes
2.
Cell ; 173(5): 1135-1149.e15, 2018 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-29754817

RESUMEN

A primary cause of disease progression in type 2 diabetes (T2D) is ß cell dysfunction due to inflammatory stress and insulin resistance. However, preventing ß cell exhaustion under diabetic conditions is a major therapeutic challenge. Here, we identify the vitamin D receptor (VDR) as a key modulator of inflammation and ß cell survival. Alternative recognition of an acetylated lysine in VDR by bromodomain proteins BRD7 and BRD9 directs association to PBAF and BAF chromatin remodeling complexes, respectively. Mechanistically, ligand promotes VDR association with PBAF to effect genome-wide changes in chromatin accessibility and enhancer landscape, resulting in an anti-inflammatory response. Importantly, pharmacological inhibition of BRD9 promotes PBAF-VDR association to restore ß cell function and ameliorate hyperglycemia in murine T2D models. These studies reveal an unrecognized VDR-dependent transcriptional program underpinning ß cell survival and identifies the VDR:PBAF/BAF association as a potential therapeutic target for T2D.


Asunto(s)
Proteínas Cromosómicas no Histona/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Receptores de Calcitriol/metabolismo , Factores de Transcripción/metabolismo , Vitamina D/farmacología , Animales , Calcitriol/análogos & derivados , Calcitriol/farmacología , Ensamble y Desensamble de Cromatina , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Humanos , Insulina/sangre , Insulina/metabolismo , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Mutagénesis Sitio-Dirigida , Fosforilación Oxidativa/efectos de los fármacos , Unión Proteica , Interferencia de ARN , ARN Guía de Kinetoplastida/genética , ARN Interferente Pequeño/metabolismo , Receptores de Calcitriol/antagonistas & inhibidores , Receptores de Calcitriol/genética , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genética , Transcripción Genética/efectos de los fármacos
3.
Immunity ; 54(7): 1561-1577.e7, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34102100

RESUMEN

A common metabolic alteration in the tumor microenvironment (TME) is lipid accumulation, a feature associated with immune dysfunction. Here, we examined how CD8+ tumor infiltrating lymphocytes (TILs) respond to lipids within the TME. We found elevated concentrations of several classes of lipids in the TME and accumulation of these in CD8+ TILs. Lipid accumulation was associated with increased expression of CD36, a scavenger receptor for oxidized lipids, on CD8+ TILs, which also correlated with progressive T cell dysfunction. Cd36-/- T cells retained effector functions in the TME, as compared to WT counterparts. Mechanistically, CD36 promoted uptake of oxidized low-density lipoproteins (OxLDL) into T cells, and this induced lipid peroxidation and downstream activation of p38 kinase. Inhibition of p38 restored effector T cell functions in vitro, and resolution of lipid peroxidation by overexpression of glutathione peroxidase 4 restored functionalities in CD8+ TILs in vivo. Thus, an oxidized lipid-CD36 axis promotes intratumoral CD8+ T cell dysfunction and serves as a therapeutic avenue for immunotherapies.


Asunto(s)
Antígenos CD36/metabolismo , Linfocitos T CD8-positivos/metabolismo , Peroxidación de Lípido/fisiología , Lipoproteínas LDL/metabolismo , Neoplasias/metabolismo , Receptores Depuradores/metabolismo , Animales , Transporte Biológico/fisiología , Línea Celular Tumoral , Células HEK293 , Humanos , Leucocitos Mononucleares/metabolismo , Linfocitos Infiltrantes de Tumor/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microambiente Tumoral/fisiología
4.
Nature ; 609(7928): 846-853, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35940205

RESUMEN

Thyroid hormones are vital in metabolism, growth and development1. Thyroid hormone synthesis is controlled by thyrotropin (TSH), which acts at the thyrotropin receptor (TSHR)2. In patients with Graves' disease, autoantibodies that activate the TSHR pathologically increase thyroid hormone activity3. How autoantibodies mimic thyrotropin function remains unclear. Here we determined cryo-electron microscopy structures of active and inactive TSHR. In inactive TSHR, the extracellular domain lies close to the membrane bilayer. Thyrotropin selects an upright orientation of the extracellular domain owing to steric clashes between a conserved hormone glycan and the membrane bilayer. An activating autoantibody from a patient with Graves' disease selects a similar upright orientation of the extracellular domain. Reorientation of the extracellular domain transduces a conformational change in the seven-transmembrane-segment domain via a conserved hinge domain, a tethered peptide agonist and a phospholipid that binds within the seven-transmembrane-segment domain. Rotation of the TSHR extracellular domain relative to the membrane bilayer is sufficient for receptor activation, revealing a shared mechanism for other glycoprotein hormone receptors that may also extend to other G-protein-coupled receptors with large extracellular domains.


Asunto(s)
Microscopía por Crioelectrón , Inmunoglobulinas Estimulantes de la Tiroides , Receptores de Tirotropina , Tirotropina , Membrana Celular/metabolismo , Enfermedad de Graves/inmunología , Enfermedad de Graves/metabolismo , Humanos , Inmunoglobulinas Estimulantes de la Tiroides/química , Inmunoglobulinas Estimulantes de la Tiroides/inmunología , Inmunoglobulinas Estimulantes de la Tiroides/farmacología , Inmunoglobulinas Estimulantes de la Tiroides/ultraestructura , Fosfolípidos/metabolismo , Dominios Proteicos , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/ultraestructura , Receptores de Tirotropina/agonistas , Receptores de Tirotropina/química , Receptores de Tirotropina/inmunología , Receptores de Tirotropina/ultraestructura , Rotación , Tirotropina/química , Tirotropina/metabolismo , Tirotropina/farmacología
5.
Nature ; 586(7831): 790-795, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32788725

RESUMEN

Serine, glycine and other nonessential amino acids are critical for tumour progression, and strategies to limit their availability are emerging as potential therapies for cancer1-3. However, the molecular mechanisms driving this response remain unclear and the effects on lipid metabolism are relatively unexplored. Serine palmitoyltransferase (SPT) catalyses the de novo biosynthesis of sphingolipids but also produces noncanonical 1-deoxysphingolipids when using alanine as a substrate4,5. Deoxysphingolipids accumulate in the context of mutations in SPTLC1 or SPTLC26,7-or in conditions of low serine availability8,9-to drive neuropathy, and deoxysphinganine has previously been investigated as an anti-cancer agent10. Here we exploit amino acid metabolism and the promiscuity of SPT to modulate the endogenous synthesis of toxic deoxysphingolipids and slow tumour progression. Anchorage-independent growth reprogrammes a metabolic network involving serine, alanine and pyruvate that drives the endogenous synthesis and accumulation of deoxysphingolipids. Targeting the mitochondrial pyruvate carrier promotes alanine oxidation to mitigate deoxysphingolipid synthesis and improve spheroid growth, similar to phenotypes observed with the direct inhibition of SPT or ceramide synthesis. Restriction of dietary serine and glycine potently induces the accumulation of deoxysphingolipids while decreasing tumour growth in xenograft models in mice. Pharmacological inhibition of SPT rescues xenograft growth in mice fed diets restricted in serine and glycine, and the reduction of circulating serine by inhibition of phosphoglycerate dehydrogenase (PHGDH) leads to the accumulation of deoxysphingolipids and mitigates tumour growth. The promiscuity of SPT therefore links serine and mitochondrial alanine metabolism to membrane lipid diversity, which further sensitizes tumours to metabolic stress.


Asunto(s)
Neoplasias/metabolismo , Neoplasias/patología , Serina/deficiencia , Esfingolípidos/química , Esfingolípidos/metabolismo , Alanina/biosíntesis , Alanina/metabolismo , Alanina/farmacología , Animales , Adhesión Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Dieta , Femenino , Glicina/biosíntesis , Glicina/deficiencia , Glicina/metabolismo , Glicina/farmacología , Células HCT116 , Humanos , Lípidos de la Membrana/química , Lípidos de la Membrana/metabolismo , Ratones , Mitocondrias/metabolismo , Neoplasias/tratamiento farmacológico , Fosfoglicerato-Deshidrogenasa/antagonistas & inhibidores , Fosfoglicerato-Deshidrogenasa/metabolismo , Ácido Pirúvico/metabolismo , Serina/sangre , Serina/farmacología , Serina C-Palmitoiltransferasa/antagonistas & inhibidores , Serina C-Palmitoiltransferasa/metabolismo , Esferoides Celulares/patología , Esfingolípidos/biosíntesis , Estrés Fisiológico/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Proc Natl Acad Sci U S A ; 120(50): e2314429120, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38055739

RESUMEN

We detected ENU-induced alleles of Mfsd1 (encoding the major facilitator superfamily domain containing 1 protein) that caused lymphopenia, splenomegaly, progressive liver pathology, and extramedullary hematopoiesis (EMH). MFSD1 is a lysosomal membrane-bound solute carrier protein with no previously described function in immunity. By proteomic analysis, we identified association between MFSD1 and both GLMP (glycosylated lysosomal membrane protein) and GIMAP5 (GTPase of immunity-associated protein 5). Germline knockout alleles of Mfsd1, Glmp, and Gimap5 each caused lymphopenia, liver pathology, EMH, and lipid deposition in the bone marrow and liver. We found that the interactions of MFSD1 and GLMP with GIMAP5 are essential to maintain normal GIMAP5 expression, which in turn is critical to support lymphocyte development and liver homeostasis that suppresses EMH. These findings identify the protein complex MFSD1-GLMP-GIMAP5 operating in hematopoietic and extrahematopoietic tissues to regulate immunity and liver homeostasis.


Asunto(s)
Proteínas de Unión al GTP , Linfopenia , Humanos , Proteínas de Unión al GTP/metabolismo , Proteómica , Hígado/metabolismo , Linfocitos/metabolismo , Linfopenia/genética , Homeostasis
7.
J Biol Chem ; 300(5): 107291, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38636661

RESUMEN

Mutations in the adiponectin receptor 1 gene (AdipoR1) lead to retinitis pigmentosa and are associated with age-related macular degeneration. This study explores the effects of AdipoR1 gene deficiency in mice, revealing a striking decline in ω3 polyunsaturated fatty acids (PUFA), an increase in ω6 fatty acids, and elevated ceramides in the retina. The AdipoR1 deficiency impairs peroxisome proliferator-activated receptor α signaling, which is crucial for FA metabolism, particularly affecting proteins associated with FA transport and oxidation in the retina and retinal pigmented epithelium. Our lipidomic and proteomic analyses indicate changes that could affect membrane composition and viscosity through altered ω3 PUFA transport and synthesis, suggesting a potential influence of AdipoR1 on these properties. Furthermore, we noted a reduction in the Bardet-Biedl syndrome proteins, which are crucial for forming and maintaining photoreceptor outer segments that are PUFA-enriched ciliary structures. Diminution in Bardet-Biedl syndrome-proteins content combined with our electron microscopic observations raises the possibility that AdipoR1 deficiency might impair ciliary function. Treatment with inhibitors of ceramide synthesis led to substantial elevation of ω3 LC-PUFAs, alleviating photoreceptor degeneration and improving retinal function. These results serve as the proof of concept for a ceramide-targeted strategy to treat retinopathies linked to PUFA deficiency, including age-related macular degeneration.


Asunto(s)
Ceramidas , Receptores de Adiponectina , Retina , Animales , Receptores de Adiponectina/metabolismo , Receptores de Adiponectina/genética , Ratones , Ceramidas/metabolismo , Retina/metabolismo , Retina/patología , Ratones Noqueados , Ácidos Grasos Insaturados/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Degeneración Macular/metabolismo , Degeneración Macular/patología , Degeneración Macular/genética
8.
N Engl J Med ; 386(4): 351-363, 2022 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-34904799

RESUMEN

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is typically treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). However, only 60% of patients are cured with R-CHOP. Polatuzumab vedotin is an antibody-drug conjugate targeting CD79b, which is ubiquitously expressed on the surface of malignant B cells. METHODS: We conducted a double-blind, placebo-controlled, international phase 3 trial to evaluate a modified regimen of R-CHOP (pola-R-CHP), in which vincristine was replaced with polatuzumab vedotin, as compared with standard R-CHOP, in patients with previously untreated intermediate-risk or high-risk DLBCL. Patients 18 to 80 years of age were randomly assigned in a 1:1 ratio to receive six cycles of either pola-R-CHP or R-CHOP, plus two cycles of rituximab alone. The primary end point was investigator-assessed progression-free survival. Secondary end points included overall survival and safety. RESULTS: Overall, 879 patients underwent randomization: 440 were assigned to the pola-R-CHP group and 439 to the R-CHOP group. After a median follow-up of 28.2 months, the percentage of patients surviving without progression was significantly higher in the pola-R-CHP group than in the R-CHOP group (76.7% [95% confidence interval (CI), 72.7 to 80.8] vs. 70.2% [95% CI, 65.8 to 74.6] at 2 years; stratified hazard ratio for progression, relapse, or death, 0.73 by Cox regression; 95% CI, 0.57 to 0.95; P = 0.02). Overall survival at 2 years did not differ significantly between the groups (88.7% [95% CI, 85.7 to 91.6] in the pola-R-CHP group and 88.6% [95% CI, 85.6 to 91.6] in the R-CHOP group; hazard ratio for death, 0.94; 95% CI, 0.65 to 1.37; P = 0.75). The safety profile was similar in the two groups. CONCLUSIONS: Among patients with previously untreated intermediate-risk or high-risk DLBCL, the risk of disease progression, relapse, or death was lower among those who received pola-R-CHP than among those who received R-CHOP. (Funded by F. Hoffmann-La Roche/Genentech; POLARIX ClinicalTrials.gov number, NCT03274492.).


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inmunoconjugados/administración & dosificación , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Adulto , Anciano , Anticuerpos Monoclonales/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Ciclofosfamida/efectos adversos , Ciclofosfamida/uso terapéutico , Método Doble Ciego , Doxorrubicina/efectos adversos , Doxorrubicina/uso terapéutico , Femenino , Humanos , Inmunoconjugados/efectos adversos , Linfoma de Células B Grandes Difuso/mortalidad , Masculino , Persona de Mediana Edad , Prednisona/efectos adversos , Prednisona/uso terapéutico , Supervivencia sin Progresión , Rituximab/efectos adversos , Rituximab/uso terapéutico , Vincristina/efectos adversos , Vincristina/uso terapéutico
9.
Nat Chem Biol ; 19(2): 187-197, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36266352

RESUMEN

Lipids contribute to the structure, development, and function of healthy brains. Dysregulated lipid metabolism is linked to aging and diseased brains. However, our understanding of lipid metabolism in aging brains remains limited. Here we examined the brain lipidome of mice across their lifespan using untargeted lipidomics. Co-expression network analysis highlighted a progressive decrease in 3-sulfogalactosyl diacylglycerols (SGDGs) and SGDG pathway members, including the potential degradation products lyso-SGDGs. SGDGs show an age-related decline specifically in the central nervous system and are associated with myelination. We also found that an SGDG dramatically suppresses LPS-induced gene expression and release of pro-inflammatory cytokines from macrophages and microglia by acting on the NF-κB pathway. The detection of SGDGs in human and macaque brains establishes their evolutionary conservation. This work enhances interest in SGDGs regarding their roles in aging and inflammatory diseases and highlights the complexity of the brain lipidome and potential biological functions in aging.


Asunto(s)
Envejecimiento , Lípidos , Animales , Humanos , Ratones , Envejecimiento/genética , Antiinflamatorios , Encéfalo/metabolismo , Microglía/metabolismo , FN-kappa B/metabolismo
10.
Int J Mol Sci ; 25(3)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38338733

RESUMEN

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic cancer originating from the malignant transformation of plasmacytoid dendritic cell precursors. This malignancy progresses rapidly, with frequent relapses and a poor overall survival rate, underscoring the urgent need for effective treatments. However, diagnosing and treating BPDCN have historically been challenging due to its rarity and the lack of standardized approaches. The recognition of BPDCN as a distinct disease entity is recent, and standardized treatment protocols are yet to be established. Traditionally, conventional chemotherapy and stem cell transplantation have been the primary methods for treating BPDCN patients. Advances in immunophenotyping and molecular profiling have identified potential therapeutic targets, leading to a shift toward CD123-targeted immunotherapies in both clinical and research settings. Ongoing developments with SL-401, IMGN632, CD123 chimeric antigen receptor (CAR) T-cells, and bispecific antibodies (BsAb) show promising advancements. However, the therapeutic effectiveness of CD123-targeting treatments needs improvement through innovative approaches and combinations of treatments with other anti-leukemic drugs. The exploration of combinations such as CD123-targeted immunotherapies with azacitidine and venetoclax is suggested to enhance antineoplastic responses and improve survival rates in BPDCN patients. In conclusion, this multifaceted approach offers hope for more effective and tailored therapeutic interventions against this challenging hematologic malignancy.


Asunto(s)
Neoplasias Hematológicas , Subunidad alfa del Receptor de Interleucina-3 , Trastornos Mieloproliferativos , Humanos , Células Dendríticas , Neoplasias Hematológicas/tratamiento farmacológico , Neoplasias Hematológicas/patología , Subunidad alfa del Receptor de Interleucina-3/efectos de los fármacos , Trastornos Mieloproliferativos/tratamiento farmacológico , Trastornos Mieloproliferativos/patología , Recurrencia Local de Neoplasia/patología , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Trasplante de Células Madre
11.
J Transl Med ; 21(1): 318, 2023 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-37170241

RESUMEN

BACKGROUND: Nivolumab is an anti-PD1 antibody that has dramatically improved metastatic melanoma patients' outcomes. Nevertheless, many patients are resistant to PD-1 inhibition, occasionally experiencing severe off-target immune toxicity. In addition, no robust and reproducible biomarkers have yet been validated to identify the correct selection of patients who will benefit from anti-PD-1 treatment avoiding unwanted side effects. However, the strength of CD26 expression on CD4+ T lymphocytes permits the characterization of three subtypes with variable degrees of responsiveness to tumors, suggesting that the presence of CD26-expressing T cells in patients might be a marker of responsiveness to PD-1-based therapies. METHODS: The frequency distribution of peripheral blood CD26-expressing cells was investigated employing multi-parametric flow cytometry in 69 metastatic melanoma patients along with clinical characteristics and blood count parameters at baseline (W0) and compared to 20 age- and sex-matched healthy controls. Percentages of baseline CD4+CD26high T cells were correlated with the outcome after nivolumab treatment. In addition, the frequency of CD4+CD26high T cells at W0 was compared with those obtained after 12 weeks (W1) of therapy in a sub-cohort of 33 patients. RESULTS: Circulating CD4+CD26high T cells were significantly reduced in melanoma patients compared to healthy subjects (p = 0.001). In addition, a significant association was observed between a low baseline percentage of CD4+CD26high T cells (< 7.3%) and clinical outcomes, measured as overall survival (p = 0.010) and progression-free survival (p = 0.014). Moreover, patients with clinical benefit from nivolumab therapy had significantly higher frequencies of circulating CD4+CD26high T cells than patients with non-clinical benefit (p = 0.004) at 12 months. Also, a higher pre-treatment proportion of circulating CD4+CD26high T cells was correlated with Disease Control Rate (p = 0.014) and best Overall Response Rate (p = 0.009) at 12 months. Interestingly, after 12 weeks (W1) of nivolumab treatment, percentages of CD4+CD26high T cells were significantly higher in comparison with the frequencies measured at W0 (p < 0.0001), aligning the cell counts with the ranges seen in the blood of healthy subjects. CONCLUSIONS: Our study firstly demonstrates that peripheral blood circulating CD4+CD26high T lymphocytes represent potential biomarkers whose perturbations are associated with reduced survival and worse clinical outcomes in melanoma patients.


Asunto(s)
Melanoma , Nivolumab , Humanos , Nivolumab/farmacología , Nivolumab/uso terapéutico , Linfocitos T , Dipeptidil Peptidasa 4/uso terapéutico , Melanoma/patología , Supervivencia sin Progresión
12.
Blood ; 137(5): 637-645, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-32870269

RESUMEN

Nivolumab, an anti-programmed death-1 (PD-1) monoclonal antibody, showed promising activity in relapsed or refractory (R/R) follicular lymphoma (FL) in a phase 1 study. We conducted a phase 2 trial to further evaluate its efficacy and safety in patients with R/R FL and to explore biomarkers of response. Patients with R/R FL and at least 2 prior lines of therapy, each containing a CD20 antibody or an alkylating agent, were treated with nivolumab 3 mg/kg every 2 weeks. The primary end point was objective response rate (ORR) assessed by an independent radiologic review committee. Biomarker analyses included gene expression profiling and multiplex immunofluorescence studies of pretreatment tumor samples. A total of 92 patients were treated. After a minimum follow-up of 12 months, ORR was 4% (4 of 92 patients). Median progression-free survival (PFS) was 2.2 months (95% confidence interval [CI], 1.9-3.6 months). Median duration of response was 11 months (95% CI, 8-14 months). Exploratory analyses suggested that responders had significantly higher proportion of CD3+ T cells in the tumor microenvironment than nonresponders, but no significant differences in PD-1 or programmed death-ligand 1 expression were observed. High expression of a set of tumor-associated macrophage genes was associated with reduced PFS (hazard ratio, 3.28; 95% CI, 1.76-6.11; P = .001). The safety profile was consistent with previous reports of nivolumab. In conclusion, nivolumab monotherapy was associated with very limited activity in patients with R/R FL. Better understanding of the immune biology of this disease may facilitate the development of effective checkpoint-based strategies. This trial was registered at www.clinicaltrials.gov as #NCT02038946.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Linfoma Folicular/tratamiento farmacológico , Nivolumab/uso terapéutico , Terapia Recuperativa , Adulto , Anciano , Antineoplásicos Alquilantes/administración & dosificación , Antineoplásicos Inmunológicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor , Femenino , Estudios de Seguimiento , Perfilación de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Linfoma Folicular/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/antagonistas & inhibidores , Nivolumab/efectos adversos , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Supervivencia sin Progresión , Recurrencia , Rituximab/administración & dosificación , Microambiente Tumoral
13.
Proc Natl Acad Sci U S A ; 117(22): 11865-11874, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32444484

RESUMEN

Striated muscle contraction involves sliding of actin thin filaments along myosin thick filaments, controlled by calcium through thin filament activation. In relaxed muscle, the two heads of myosin interact with each other on the filament surface to form the interacting-heads motif (IHM). A key question is how both heads are released from the surface to approach actin and produce force. We used time-resolved synchrotron X-ray diffraction to study tarantula muscle before and after tetani. The patterns showed that the IHM is present in live relaxed muscle. Tetanic contraction produced only a very small backbone elongation, implying that mechanosensing-proposed in vertebrate muscle-is not of primary importance in tarantula. Rather, thick filament activation results from increases in myosin phosphorylation that release a fraction of heads to produce force, with the remainder staying in the ordered IHM configuration. After the tetanus, the released heads slowly recover toward the resting, helically ordered state. During this time the released heads remain close to actin and can quickly rebind, enhancing the force produced by posttetanic twitches, structurally explaining posttetanic potentiation. Taken together, these results suggest that, in addition to stretch activation in insects, two other mechanisms for thick filament activation have evolved to disrupt the interactions that establish the relaxed helices of IHMs: one in invertebrates, by either regulatory light-chain phosphorylation (as in arthropods) or Ca2+-binding (in mollusks, lacking phosphorylation), and another in vertebrates, by mechanosensing.


Asunto(s)
Músculo Estriado/fisiología , Miosinas/metabolismo , Fosforilación/fisiología , Citoesqueleto de Actina/química , Citoesqueleto de Actina/metabolismo , Animales , Artrópodos/fisiología , Evolución Molecular , Invertebrados/fisiología , Modelos Moleculares , Contracción Muscular , Relajación Muscular , Miosinas/química , Estructura Secundaria de Proteína , Arañas/fisiología , Vertebrados/fisiología
14.
Sensors (Basel) ; 23(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36679712

RESUMEN

The sharing of cyberthreat information within a community or group of entities is possible due to solutions such as the Malware Information Sharing Platform (MISP). However, the MISP was considered limited if its information was deemed as classified or shared only for a given period of time. A solution using searchable encryption techniques that better control the sharing of information was previously proposed by the same authors. This paper describes a prototype implementation for two key functionalities of the previous solution, considering multiple entities sharing information with each other: the symmetric key generation of a sharing group and the functionality to update a shared index. Moreover, these functionalities are evaluated regarding their performance, and enhancements are proposed to improve the performance of the implementation regarding its execution time. As the main result, the duration of the update process was shortened from around 2922 s to around 302 s, when considering a shared index with 100,000 elements. From the security analysis performed, the implementation can be considered secure, thus confirming the secrecy of the exchanged nonces. The limitations of the current implementation are depicted, and future work is pointed out.


Asunto(s)
Algoritmos , Seguridad Computacional , Confidencialidad , Difusión de la Información
15.
Radiol Med ; 128(2): 222-233, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36658367

RESUMEN

OBJECTIVES: To develop a structured reporting (SR) template for whole-body CT examinations of polytrauma patients, based on the consensus of a panel of emergency radiology experts from the Italian Society of Medical and Interventional Radiology. METHODS: A multi-round Delphi method was used to quantify inter-panelist agreement for all SR sections. Internal consistency for each section and quality analysis in terms of average inter-item correlation were evaluated by means of the Cronbach's alpha (Cα) correlation coefficient. RESULTS: The final SR form included 118 items (6 in the "Patient Clinical Data" section, 4 in the "Clinical Evaluation" section, 9 in the "Imaging Protocol" section, and 99 in the "Report" section). The experts' overall mean score and sum of scores were 4.77 (range 1-5) and 257.56 (range 206-270) in the first Delphi round, and 4.96 (range 4-5) and 208.44 (range 200-210) in the second round, respectively. In the second Delphi round, the experts' overall mean score was higher than in the first round, and standard deviation was lower (3.11 in the second round vs 19.71 in the first round), reflecting a higher expert agreement in the second round. Moreover, Cα was higher in the second round than in the first round (0.97 vs 0.87). CONCLUSIONS: Our SR template for whole-body CT examinations of polytrauma patients is based on a strong agreement among panel experts in emergency radiology and could improve communication between radiologists and the trauma team.


Asunto(s)
Traumatismo Múltiple , Radiología , Humanos , Técnica Delphi , Consenso , Tomografía Computarizada por Rayos X
16.
Blood ; 135(13): 996-1007, 2020 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-31977002

RESUMEN

Treatment options for relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) are limited, with no standard of care; prognosis is poor, with 4- to 6-month median survival. Avadomide (CC-122) is a cereblon-modulating agent with immunomodulatory and direct antitumor activities. This phase 1 dose-expansion study assessed safety and clinical activity of avadomide monotherapy in patients with de novo R/R DLBCL and transformed lymphoma. Additionally, a novel gene expression classifier, which identifies tumors with a high immune cell infiltration, was shown to enrich for response to avadomide in R/R DLBCL. Ninety-seven patients with R/R DLBCL, including 12 patients with transformed lymphoma, received 3 to 5 mg avadomide administered on continuous or intermittent schedules until unacceptable toxicity, disease progression, or withdrawal. Eighty-two patients (85%) experienced ≥1 grade 3/4 treatment-emergent adverse events (AEs), most commonly neutropenia (51%), infections (24%), anemia (12%), and febrile neutropenia (10%). Discontinuations because of AEs occurred in 10% of patients. Introduction of an intermittent 5/7-day schedule improved tolerability and reduced frequency and severity of neutropenia, febrile neutropenia, and infections. Among 84 patients with de novo R/R DLBCL, overall response rate (ORR) was 29%, including 11% complete response (CR). Responses were cell-of-origin independent. Classifier-positive DLBCL patients (de novo) had an ORR of 44%, median progression-free survival (mPFS) of 6 months, and 16% CR vs an ORR of 19%, mPFS of 1.5 months, and 5% CR in classifier-negative patients (P = .0096). Avadomide is being evaluated in combination with other antilymphoma agents. This trial was registered at www.clinicaltrials.gov as #NCT01421524.


Asunto(s)
Antineoplásicos/uso terapéutico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/patología , Piperidonas/uso terapéutico , Quinazolinonas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Biomarcadores , Resistencia a Antineoplásicos , Femenino , Humanos , Inmunofenotipificación , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/mortalidad , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Oportunidad Relativa , Piperidonas/administración & dosificación , Piperidonas/efectos adversos , Piperidonas/farmacocinética , Pronóstico , Quinazolinonas/administración & dosificación , Quinazolinonas/efectos adversos , Quinazolinonas/farmacocinética , Recurrencia , Retratamiento , Linfocitos T/inmunología , Linfocitos T/metabolismo , Resultado del Tratamiento
17.
Haematologica ; 107(7): 1633-1642, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34407602

RESUMEN

This retrospective analysis of the phase III GOYA study investigated the prognostic value of baseline metabolic tumor volume parameters and maximum standardized uptake values for overall and progression-free survival (PFS) in treatment-naïve diffuse large B-cell lymphoma. Baseline total metabolic tumor volume (determined for tumors >1 mL using a threshold of 1.5 times the mean liver standardized uptake value +2 standard deviations), total lesion glycolysis, and maximum standardized uptake value positron emission tomography data were dichotomized based on receiver operating characteristic analysis and divided into quartiles by baseline population distribution. Of 1,418 enrolled patients, 1,305 had a baseline positron emission tomography scan with detectable lesions. Optimal cut-offs were 366 cm3 for total metabolic tumor volume and 3,004 g for total lesion glycolysis. High total metabolic tumor volume and total lesion glycolysis predicted poorer PFS, with associations retained after adjustment for baseline and disease characteristics (high total metabolic tumor volume hazard ratio: 1.71, 95% confidence interval [CI]: 1.35- 2.18; total lesion glycolysis hazard ratio: 1.46; 95% CI: 1.15-1.86). Total metabolic tumor volume was prognostic for PFS in subgroups with International Prognostic Index scores 0-2 and 3-5, and those with different cell-of-origin subtypes. Maximum standardized uptake value had no prognostic value in this setting. High total metabolic tumor volume associated with high International Prognostic Index or non-germinal center B-cell classification identified the highest-risk cohort for unfavorable prognosis. In conclusion, baseline total metabolic tumor volume and total lesion glycolysis are independent predictors of PFS in patients with diffuse large B-cell lymphoma after first-line immunochemotherapy.


Asunto(s)
Fluorodesoxiglucosa F18 , Linfoma de Células B Grandes Difuso , Glucólisis , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones , Pronóstico , Radiofármacos , Estudios Retrospectivos , Carga Tumoral
18.
Cochrane Database Syst Rev ; 7: CD009608, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35866377

RESUMEN

BACKGROUND: Schizophrenia is a disabling psychotic disorder characterised by positive symptoms of delusions, hallucinations, disorganised speech and behaviour; and negative symptoms such as affective flattening and lack of motivation. Cognitive behavioural therapy (CBT) is a psychological intervention that aims to change the way in which a person interprets and evaluates their experiences, helping them to identify and link feelings and patterns of thinking that underpin distress. CBT models targeting symptoms of psychosis (CBTp) have been developed for many mental health conditions including schizophrenia. CBTp has been suggested as a useful add-on therapy to medication for people with schizophrenia. While CBT for people with schizophrenia was mainly developed as an individual treatment, it is expensive and a group approach may be more cost-effective. Group CBTp can be defined as a group intervention targeting psychotic symptoms, based on the cognitive behavioural model. In group CBTp, people work collaboratively on coping with distressing hallucinations, analysing evidence for their delusions, and developing problem-solving and social skills. However, the evidence for effectiveness is far from conclusive. OBJECTIVES: To investigate efficacy and acceptability of group CBT applied to psychosis compared with standard care or other psychosocial interventions, for people with schizophrenia or schizoaffective disorder. SEARCH METHODS: On 10 February 2021, we searched the Cochrane Schizophrenia Group's Study-Based Register of Trials, which is based on CENTRAL, MEDLINE, Embase, four other databases and two trials registries. We handsearched the reference lists of relevant papers and previous systematic reviews and contacted experts in the field for supplemental data. SELECTION CRITERIA: We selected randomised controlled trials allocating adults with schizophrenia to receive either group CBT for schizophrenia, compared with standard care, or any other psychosocial intervention (group or individual). DATA COLLECTION AND ANALYSIS: We complied with Cochrane recommended standard of conduct for data screening and collection. Where possible, we calculated risk ratio (RR) and 95% confidence interval (CI) for binary data and mean difference (MD) and 95% CI for continuous data. We used a random-effects model for analyses. We assessed risk of bias for included studies and created a summary of findings table using GRADE. MAIN RESULTS: The review includes 24 studies (1900 participants). All studies compared group CBTp with treatments that a person with schizophrenia would normally receive in a standard mental health service (standard care) or any other psychosocial intervention (group or individual). None of the studies compared group CBTp with individual CBTp. Overall risk of bias within the trials was moderate to low. We found no studies reporting data for our primary outcome of clinically important change. With regard to numbers of participants leaving the study early, group CBTp has little or no effect compared to standard care or other psychosocial interventions (RR 1.22, 95% CI 0.94 to 1.59; studies = 13, participants = 1267; I2 = 9%; low-certainty evidence). Group CBTp may have some advantage over standard care or other psychosocial interventions for overall mental state at the end of treatment for endpoint scores on the Positive and Negative Syndrome Scale (PANSS) total (MD -3.73, 95% CI -4.63 to -2.83; studies = 12, participants = 1036; I2 = 5%; low-certainty evidence). Group CBTp seems to have little or no effect on PANSS positive symptoms (MD -0.45, 95% CI -1.30 to 0.40; studies =8, participants = 539; I2 = 0%) and on PANSS negative symptoms scores at the end of treatment (MD -0.73, 95% CI -1.68 to 0.21; studies = 9, participants = 768; I2 = 65%). Group CBTp seems to have an advantage over standard care or other psychosocial interventions on global functioning measured by Global Assessment of Functioning (GAF; MD -3.61, 95% CI -6.37 to -0.84; studies = 5, participants = 254; I2 = 0%; moderate-certainty evidence), Personal and Social Performance Scale (PSP; MD 3.30, 95% CI 2.00 to 4.60; studies = 1, participants = 100), and Social Disability Screening Schedule (SDSS; MD -1.27, 95% CI -2.46 to -0.08; studies = 1, participants = 116). Service use data were equivocal with no real differences between treatment groups for number of participants hospitalised (RR 0.78, 95% CI 0.38 to 1.60; studies = 3, participants = 235; I2 = 34%). There was no clear difference between group CBTp and standard care or other psychosocial interventions endpoint scores on depression and quality of life outcomes, except for quality of life measured by World Health Organization Quality of Life Assessment Instrument (WHOQOL-BREF) Psychological domain subscale (MD -4.64, 95% CI -9.04 to -0.24; studies = 2, participants = 132; I2 = 77%). The studies did not report relapse or adverse effects. AUTHORS' CONCLUSIONS: Group CBTp appears to be no better or worse than standard care or other psychosocial interventions for people with schizophrenia in terms of leaving the study early, service use and general quality of life. Group CBTp seems to be more effective than standard care or other psychosocial interventions on overall mental state and global functioning scores. These results may not be widely applicable as each study had a low sample size. Therefore, no firm conclusions concerning the efficacy of group CBTp for people with schizophrenia can currently be made. More high-quality research, reporting useable and relevant data is needed.


Asunto(s)
Terapia Cognitivo-Conductual , Trastornos Psicóticos , Esquizofrenia , Adulto , Terapia Cognitivo-Conductual/métodos , Alucinaciones/etiología , Alucinaciones/terapia , Humanos , Trastornos Psicóticos/terapia , Calidad de Vida , Esquizofrenia/tratamiento farmacológico
19.
Int J Mol Sci ; 23(4)2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35216512

RESUMEN

Diabetes mellitus is a comprehensive expression to identify a condition of chronic hyperglycemia whose causes derive from different metabolic disorders characterized by altered insulin secretion or faulty insulin effect on its targets or often both mechanisms. Diabetes and atherosclerosis are, from the point of view of cardio- and cerebrovascular risk, two complementary diseases. Beyond shared aspects such as inflammation and oxidative stress, there are multiple molecular mechanisms by which they feed off each other: chronic hyperglycemia and advanced glycosylation end-products (AGE) promote 'accelerated atherosclerosis' through the induction of endothelial damage and cellular dysfunction. These diseases impact the vascular system and, therefore, the risk of developing cardio- and cerebrovascular events is now evident, but the observation of this significant correlation has its roots in past decades. Cerebrovascular complications make diabetic patients 2-6 times more susceptible to a stroke event and this risk is magnified in younger individuals and in patients with hypertension and complications in other vascular beds. In addition, when patients with diabetes and hyperglycemia experience an acute ischemic stroke, they are more likely to die or be severely disabled and less likely to benefit from the one FDA-approved therapy, intravenous tissue plasminogen activator. Experimental stroke models have revealed that chronic hyperglycemia leads to deficits in cerebrovascular structure and function that may explain some of the clinical observations. Increased edema, neovascularization, and protease expression as well as altered vascular reactivity and tone may be involved and point to potential therapeutic targets. Further study is needed to fully understand this complex disease state and the breadth of its manifestation in the cerebrovasculature.


Asunto(s)
Diabetes Mellitus/patología , Accidente Cerebrovascular Isquémico/patología , Animales , Diabetes Mellitus/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Humanos , Hiperglucemia/metabolismo , Hiperglucemia/patología , Hipertensión/metabolismo , Hipertensión/patología , Accidente Cerebrovascular Isquémico/metabolismo
20.
Int J Mol Sci ; 23(5)2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35269587

RESUMEN

There is growing evidence that hypertension is the most important vascular risk factor for the development and progression of cardiovascular and cerebrovascular diseases. The brain is an early target of hypertension-induced organ damage and may manifest as stroke, subclinical cerebrovascular abnormalities and cognitive decline. The pathophysiological mechanisms of these harmful effects remain to be completely clarified. Hypertension is well known to alter the structure and function of cerebral blood vessels not only through its haemodynamics effects but also for its relationships with endothelial dysfunction, oxidative stress and inflammation. In the last several years, new possible mechanisms have been suggested to recognize the molecular basis of these pathological events. Accordingly, this review summarizes the factors involved in hypertension-induced brain complications, such as haemodynamic factors, endothelial dysfunction and oxidative stress, inflammation and intervention of innate immune system, with particular regard to the role of Toll-like receptors that have to be considered dominant components of the innate immune system. The complete definition of their prognostic role in the development and progression of hypertensive brain damage will be of great help in the identification of new markers of vascular damage and the implementation of innovative targeted therapeutic strategies.


Asunto(s)
Encéfalo/fisiopatología , Hipertensión/complicaciones , Receptores Toll-Like/metabolismo , Animales , Encéfalo/metabolismo , Progresión de la Enfermedad , Hemodinámica , Humanos , Hipertensión/metabolismo , Hipertensión/fisiopatología , Inmunidad Innata , Estrés Oxidativo
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