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1.
Genes Dev ; 35(5-6): 367-378, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33602873

RESUMEN

Thyroid hormones (THs) are powerful regulators of metabolism with major effects on body weight, cholesterol, and liver fat that have been exploited pharmacologically for many years. Activation of gene expression by TH action is canonically ascribed to a hormone-dependent "switch" from corepressor to activator binding to thyroid hormone receptors (TRs), while the mechanism of TH-dependent repression is controversial. To address this, we generated a mouse line in which endogenous TRß1 was epitope-tagged to allow precise chromatin immunoprecipitation at the low physiological levels of TR and defined high-confidence binding sites where TRs functioned at enhancers regulated in the same direction as the nearest gene in a TRß-dependent manner. Remarkably, although positive and negative regulation by THs have been ascribed to different mechanisms, TR binding was highly enriched at canonical DR4 motifs irrespective of the transcriptional direction of the enhancer. The canonical NCoR1/HDAC3 corepressor complex was reduced but not completely dismissed by TH and, surprisingly, similar effects were seen at enhancers associated with negatively as well as positively regulated genes. Conversely, coactivator CBP was found at all TH-regulated enhancers, with transcriptional activity correlating with the ratio of CBP to NCoR rather than their presence or absence. These results demonstrate that, in contrast to the canonical "all or none" coregulator switch model, THs regulate gene expression by orchestrating a shift in the relative binding of corepressors and coactivators.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Receptores beta de Hormona Tiroidea/metabolismo , Hormonas Tiroideas/metabolismo , Animales , Sitios de Unión , Cromatina/química , Cromatina/metabolismo , Elementos de Facilitación Genéticos , Ratones , Modelos Animales , Unión Proteica , Receptores beta de Hormona Tiroidea/genética
2.
Plant Cell ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38701340

RESUMEN

Improving photosynthesis, the fundamental process by which plants convert light energy into chemical energy, is a key area of research with great potential for enhancing sustainable agricultural productivity and addressing global food security challenges. This perspective delves into the latest advancements and approaches aimed at optimizing photosynthetic efficiency. Our discussion encompasses the entire process, beginning with light harvesting and its regulation and progressing through the bottleneck of electron transfer. We then delve into the carbon reactions of photosynthesis, focusing on strategies targeting the enzymes of the Calvin-Benson-Bassham (CBB) cycle. Additionally, we explore methods to increase CO2 concentration near the Rubisco, the enzyme responsible for the first step of CBB cycle, drawing inspiration from various photosynthetic organisms, and conclude this section by examining ways to enhance CO2 delivery into leaves. Moving beyond individual processes, we discuss two approaches to identifying key targets for photosynthesis improvement: systems modeling and the study of natural variation. Finally, we revisit some of the strategies mentioned above to provide a holistic view of the improvements, analyzing their impact on nitrogen use efficiency and on canopy photosynthesis.

3.
Nature ; 591(7849): 288-292, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33658715

RESUMEN

The evolutionarily conserved target of rapamycin (TOR) kinase acts as a master regulator that coordinates cell proliferation and growth by integrating nutrient, energy, hormone and stress signals in all eukaryotes1,2. Research has focused mainly on TOR-regulated translation, but how TOR orchestrates the global transcriptional network remains unclear. Here we identify ethylene-insensitive protein 2 (EIN2), a central integrator3-5 that shuttles between the cytoplasm and the nucleus, as a direct substrate of TOR in Arabidopsis thaliana. Glucose-activated TOR kinase directly phosphorylates EIN2 to prevent its nuclear localization. Notably, the rapid global transcriptional reprogramming that is directed by glucose-TOR signalling is largely compromised in the ein2-5 mutant, and EIN2 negatively regulates the expression of a wide range of target genes of glucose-activated TOR that are involved in DNA replication, cell wall and lipid synthesis and various secondary metabolic pathways. Chemical, cellular and genetic analyses reveal that cell elongation and proliferation processes that are controlled by the glucose-TOR-EIN2 axis are decoupled from canonical ethylene-CTR1-EIN2 signalling, and mediated by different phosphorylation sites. Our findings reveal a molecular mechanism by which a central signalling hub is shared but differentially modulated by diverse signalling pathways using distinct phosphorylation codes that can be specified by upstream protein kinases.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Desarrollo de la Planta , Receptores de Superficie Celular/metabolismo , Transducción de Señal , Arabidopsis/citología , Arabidopsis/genética , Dominio Catalítico , Proteínas de Unión al ADN/metabolismo , Etilenos/metabolismo , Glucosa/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Meristema/metabolismo , Fosforilación , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas Quinasas/metabolismo , Especificidad por Sustrato , Factores de Transcripción/metabolismo , Transcriptoma
4.
Nat Mater ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977883

RESUMEN

Despite the potential of oral immunotherapy against food allergy, adverse reactions and loss of desensitization hinder its clinical uptake. Dysbiosis of the gut microbiota is implicated in the increasing prevalence of food allergy, which will need to be regulated to enable for an effective oral immunotherapy against food allergy. Here we report an inulin gel formulated with an allergen that normalizes the dysregulated ileal microbiota and metabolites in allergic mice, establishes allergen-specific oral tolerance and achieves robust oral immunotherapy efficacy with sustained unresponsiveness in food allergy models. These positive outcomes are associated with enhanced allergen uptake by antigen-sampling dendritic cells in the small intestine, suppressed pathogenic type 2 immune responses, increased interferon-γ+ and interleukin-10+ regulatory T cell populations, and restored ileal abundances of Eggerthellaceae and Enterorhabdus in allergic mice. Overall, our findings underscore the therapeutic potential of the engineered allergen gel as a suitable microbiome-modulating platform for food allergy and other allergic diseases.

5.
Proc Natl Acad Sci U S A ; 119(49): e2209884119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36454759

RESUMEN

Cone photoreceptor diversity allows detection of wavelength information in light, the first step in color (chromatic) vision. In most mammals, cones express opsin photopigments for sensitivity to medium/long (M, "green") or short (S, "blue") wavelengths and are differentially arrayed over the retina. Cones appear early in retinal neurogenesis but little is understood of the subsequent control of diversity of these postmitotic neurons, because cone populations are sparse and, apart from opsins, poorly defined. It is also a challenge to distinguish potentially subtle differences between cell subtypes within a lineage. Therefore, we derived a Cre driver to isolate individual M and S opsin-enriched cones, which are distributed in counter-gradients over the mouse retina. Fine resolution transcriptome analyses identified expression gradients for groups of genes. The postnatal emergence of gradients indicated divergent differentiation of cone precursors during maturation. Using genetic tagging, we demonstrated a role for thyroid hormone receptor ß2 (TRß2) in control of gradient genes, many of which are enriched for TRß2 binding sites and TRß2-regulated open chromatin. Deletion of TRß2 resulted in poorly distinguished cones regardless of retinal location. We suggest that TRß2 controls a bipotential transcriptional state to promote cone diversity and the chromatic potential of the species.


Asunto(s)
Receptores de Hormona Tiroidea , Células Fotorreceptoras Retinianas Conos , Animales , Ratones , Regulación de la Expresión Génica , Opsinas/genética , Retina , Opsinas de Bastones/genética
6.
J Biol Chem ; 299(8): 104984, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37390988

RESUMEN

HIV-1 replication in primary monocyte-derived macrophages (MDMs) is kinetically restricted at the reverse transcription step due to the low deoxynucleoside triphosphates (dNTP) pools established by host dNTPase, SAM and HD domain containing protein 1 (SAMHD1). Lentiviruses such as HIV-2 and some Simian immunodeficiency virus counteract this restriction using viral protein X (Vpx), which proteosomally degrades SAMHD1 and elevates intracellular dNTP pools. However, how dNTP pools increase after Vpx degrades SAMHD1 in nondividing MDMs where no active dNTP biosynthesis is expected to exists remains unclear. In this study, we monitored known dNTP biosynthesis machinery during primary human monocyte differentiation to MDMs and unexpectedly found MDMs actively express dNTP biosynthesis enzymes such as ribonucleotide reductase, thymidine kinase 1, and nucleoside-diphosphate kinase. During differentiation from monocytes the expression levels of several biosynthesis enzymes are upregulated, while there is an increase in inactivating SAMHD1 phosphorylation. Correspondingly, we observed significantly lower levels of dNTPs in monocytes compared to MDMs. Without dNTP biosynthesis availability, Vpx failed to elevate dNTPs in monocytes, despite SAMHD1 degradation. These extremely low monocyte dNTP concentrations, which cannot be elevated by Vpx, impaired HIV-1 reverse transcription in a biochemical simulation. Furthermore, Vpx failed to rescue the transduction efficiency of a HIV-1 GFP vector in monocytes. Collectively, these data suggest that MDMs harbor active dNTP biosynthesis and Vpx requires this dNTP biosynthesis to elevate dNTP levels to effectively counteract SAMHD1 and relieve the kinetic block to HIV-1 reverse transcription in MDMs.


Asunto(s)
VIH-1 , Proteínas de Unión al GTP Monoméricas , Nucleótidos , Proteína 1 que Contiene Dominios SAM y HD , Proteínas Reguladoras y Accesorias Virales , Animales , Humanos , VIH-1/metabolismo , Lentivirus/metabolismo , Macrófagos/metabolismo , Monocitos/metabolismo , Proteínas de Unión al GTP Monoméricas/genética , Proteínas de Unión al GTP Monoméricas/metabolismo , Nucleótidos/metabolismo , Proteína 1 que Contiene Dominios SAM y HD/metabolismo , Proteínas Reguladoras y Accesorias Virales/metabolismo
7.
J Biol Chem ; 299(8): 105002, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37394003

RESUMEN

Acrylamide, a common food contaminant, is metabolically activated to glycidamide, which reacts with DNA at the N7 position of dG, forming N7-(2-carbamoyl-2-hydroxyethyl)-dG (GA7dG). Owing to its chemical lability, the mutagenic potency of GA7dG has not yet been clarified. We found that GA7dG undergoes ring-opening hydrolysis to form N6-(2-deoxy-d-erythro-pentofuranosyl)-2,6-diamino-3,4-dihydro-4-oxo-5-[N-(2-carbamoyl-2-hydroxyethyl)formamido]pyrimidine (GA-FAPy-dG), even at neutral pH. Therefore, we aimed to examine the effects of GA-FAPy-dG on the efficiency and fidelity of DNA replication using an oligonucleotide carrying GA-FAPy-9-(2-deoxy-2-fluoro-ß-d-arabinofuranosyl)guanine (dfG), a 2'-fluorine substituted analog of GA-FAPy-dG. GA-FAPy-dfG inhibited primer extension by both human replicative DNA polymerase ε and the translesion DNA synthesis polymerases (Polη, Polι, Polκ, and Polζ) and reduced the replication efficiency by less than half in human cells, with single base substitution at the site of GA-FAPy-dfG. Unlike other formamidopyrimidine derivatives, the most abundant mutation was G:C > A:T transition, which was decreased in Polκ- or REV1-KO cells. Molecular modeling suggested that a 2-carbamoyl-2-hydroxyethyl group at the N5 position of GA-FAPy-dfG can form an additional H-bond with thymidine, thereby contributing to the mutation. Collectively, our results provide further insight into the mechanisms underlying the mutagenic effects of acrylamide.


Asunto(s)
Aductos de ADN , Mutágenos , Humanos , Acrilamidas , Desoxiguanosina , ADN , Daño del ADN , Replicación del ADN , Mutagénesis , Mutágenos/toxicidad , Contaminación de Alimentos
8.
Crit Rev Eukaryot Gene Expr ; 34(6): 37-60, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38912962

RESUMEN

Regenerative dental medicine continuously expands to improve treatments for prevalent clinical problems in dental and oral medicine. Stem cell based translational opportunities include regenerative therapies for tooth restoration, root canal therapy, and inflammatory processes (e.g., periodontitis). The potential of regenerative approaches relies on the biological properties of dental stem cells. These and other multipotent somatic mesenchymal stem cell (MSC) types can in principle be applied as either autologous or allogeneic sources in dental procedures. Dental stem cells have distinct developmental origins and biological markers that determine their translational utility. Dental regenerative medicine is supported by mechanistic knowledge of the molecular pathways that regulate dental stem cell growth and differentiation. Cell fate determination and lineage progression of dental stem cells is regulated by multiple cell signaling pathways (e.g., WNTs, BMPs) and epigenetic mechanisms, including DNA modifications, histone modifications, and non-coding RNAs (e.g., miRNAs and lncRNAs). This review also considers a broad range of novel approaches in which stem cells are applied in combination with biopolymers, ceramics, and composite materials, as well as small molecules (agonistic or anti-agonistic ligands) and natural compounds. Materials that mimic the microenvironment of the stem cell niche are also presented. Promising concepts in bone and dental tissue engineering continue to drive innovation in dental and non-dental restorative procedures.


Asunto(s)
Materiales Biocompatibles , Medicina Regenerativa , Humanos , Medicina Regenerativa/métodos , Ingeniería de Tejidos/métodos , Células Madre/citología , Células Madre/metabolismo , Diferenciación Celular , Células Madre Mesenquimatosas/metabolismo , Animales
9.
Clin Immunol ; 258: 109848, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38036277

RESUMEN

Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by thrombotic events and/or pregnancy complications in the presence of persistently positive antiphospholipid antibodies (aPL). Although long-term anticoagulation with vitamin K antagonists is considered standard of care, there is an unmet need for safe therapeutics as primary thromboprophylaxis or adjuncts to standard of care in APS. APS is driven by oxidative stress, procoagulant, proinflammatory and angiogenic pathways. For these reasons there has been an increased interest into the investigation of antithrombotic, anti-inflammatory and anti-oxidant properties of natural supplements in APS. The objective of this review is to summarize the mechanistic, epidemiologic and clinical evidence behind the use of natural supplements in APS, with a specific focus on vitamin D, omega-3 fatty acids, coenzyme Q10, gingerol, and isoquercetin. This review should serve as a compelling argument for the future study of natural supplements in APS.


Asunto(s)
Síndrome Antifosfolípido , Complicaciones del Embarazo , Tromboembolia Venosa , Femenino , Embarazo , Humanos , Anticoagulantes/uso terapéutico , Tromboembolia Venosa/complicaciones , Tromboembolia Venosa/tratamiento farmacológico , Anticuerpos Antifosfolípidos , Complicaciones del Embarazo/tratamiento farmacológico
10.
Radiology ; 311(1): e232188, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38591973

RESUMEN

Background The Society of Radiologists in Ultrasound (SRU) has proposed thresholds for acoustic radiation force impulse techniques to diagnose compensated advanced chronic liver disease (cACLD). However, the diagnostic performance of these thresholds has not been extensively validated. Purpose To validate the SRU thresholds in patients with chronic liver disease who underwent supersonic shear imaging and, if suboptimal diagnostic performance is observed, to identify optimal values for diagnosing cACLD. Materials and Methods This retrospective single-center study included high-risk patients with chronic liver disease who had liver stiffness (LS) measurements and had undergone endoscopy or liver biopsy between January 2018 and December 2021. Patients were randomly allocated to test and validation sets. cACLD was defined as varices at endoscopy and/or severe fibrosis or cirrhosis at liver biopsy. The diagnostic performance of the SRU guidelines was evaluated, and optimal threshold values were identified using receiver operating characteristic (ROC) curve analysis. Results A total of 1180 patients (median age, 57 years [IQR, 50-64 years]; 761 men), of whom 544 (46%) had cACLD, were included. With the SRU recommended thresholds of less than 9 kPa and greater than 13 kPa in the test set (n = 786), the sensitivity and specificity for ruling out and ruling in cACLD were 81% (303 of 374 patients; 95% CI: 77, 85) and 92% (380 of 412 patients; 95% CI: 89, 94), respectively. In ROC curve analysis, the identified optimal threshold values were less than 7 kPa and greater than 12 kPa, showing 91% sensitivity (340 of 374 patients; 95% CI: 88, 93) for ruling out cACLD and 91% specificity (373 of 412 patients; 95% CI: 87, 93) for ruling in cACLD, respectively. In the validation set (n = 394), the optimal thresholds showed 91% sensitivity (155 of 170 patients; 95% CI: 86, 95) and 92% specificity (206 of 224 patients; 95% CI: 88, 95). Conclusion Compared with the SRU guidelines, the dual LS threshold values of less than 7 kPa and greater than 12 kPa were better for diagnosing cACLD. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Barr in this issue.


Asunto(s)
Diagnóstico por Imagen , Hepatopatías , Masculino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Hepatopatías/diagnóstico por imagen , Cirrosis Hepática/diagnóstico por imagen , Biopsia
11.
Am J Physiol Regul Integr Comp Physiol ; 327(1): R54-R65, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38738295

RESUMEN

Obesity is a major public health issue due to its association with type 2 diabetes, hypertension, and other cardiovascular risks. The BBSome, a complex of eight conserved Bardet-Biedl syndrome (BBS) proteins, has emerged as a key regulator of energy and glucose homeostasis as well as cardiovascular function. However, the importance of adipocyte BBSome in controlling these physiological processes is not clear. Here, we show that adipocyte-specific constitutive disruption of the BBSome through selective deletion of the Bbs1 gene adiponectin (AdipoCre/Bbs1fl/fl mice) does not affect body weight under normal chow or high-fat and high-sucrose diet (HFHSD). However, constitutive BBSome deficiency caused impairment in glucose tolerance and insulin sensitivity. Similar phenotypes were observed after inducible adipocyte-specific disruption of the BBSome (AdipoCreERT2/Bbs1fl/fl mice). Interestingly, a significant increase in renal sympathetic nerve activity, measured using multifiber recording in the conscious state, was observed in AdipoCre/Bbs1fl/fl mice on both chow and HFHSD. A significant increase in tail-cuff arterial pressure was also observed in chow-fed AdipoCre/Bbs1fl/fl mice, but this was not reproduced when arterial pressure was measured by radiotelemetry. Moreover, AdipoCre/Bbs1fl/fl mice had no significant alterations in vascular reactivity. On the other hand, AdipoCre/Bbs1fl/fl mice displayed impaired baroreceptor reflex sensitivity when fed HFHSD, but not on normal chow. Taken together, these data highlight the relevance of the adipocyte BBSome for the regulation of glucose homeostasis and sympathetic traffic. The BBSome also contributes to baroreflex sensitivity under HFHSD, but not normal chow.NEW & NOTEWORTHY The current study show how genetic manipulation of fat cells impacts various functions of the body including sensitivity to the hormone insulin.


Asunto(s)
Adipocitos , Adiponectina , Animales , Adipocitos/metabolismo , Adiponectina/metabolismo , Adiponectina/genética , Ratones , Resistencia a la Insulina , Masculino , Obesidad/fisiopatología , Obesidad/metabolismo , Obesidad/genética , Ratones Noqueados , Sistema Nervioso Simpático/fisiopatología , Dieta Alta en Grasa , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Enfermedades del Sistema Nervioso Autónomo/genética , Enfermedades del Sistema Nervioso Autónomo/metabolismo , Síndrome de Bardet-Biedl/genética , Síndrome de Bardet-Biedl/fisiopatología , Síndrome de Bardet-Biedl/metabolismo , Proteínas Asociadas a Microtúbulos
12.
Nat Immunol ; 13(8): 744-52, 2012 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-22729248

RESUMEN

Langerhans cells (LCs) are epidermal dendritic cells with incompletely understood origins that associate with hair follicles for unknown reasons. Here we show that in response to external stress, mouse hair follicles recruited Gr-1(hi) monocyte-derived precursors of LCs whose epidermal entry was dependent on the chemokine receptors CCR2 and CCR6, whereas the chemokine receptor CCR8 inhibited the recruitment of LCs. Distinct hair-follicle regions had differences in their expression of ligands for CCR2 and CCR6. The isthmus expressed the chemokine CCL2; the infundibulum expressed the chemokine CCL20; and keratinocytes in the bulge produced the chemokine CCL8, which is the ligand for CCR8. Thus, distinct hair-follicle keratinocyte subpopulations promoted or inhibited repopulation with LCs via differences in chemokine production, a feature also noted in humans. Pre-LCs failed to enter hairless skin in mice or humans, which establishes hair follicles as portals for LCs.


Asunto(s)
Quimiocinas/biosíntesis , Folículo Piloso/inmunología , Células de Langerhans/fisiología , Estrés Fisiológico , Alopecia , Animales , Movimiento Celular , Quimiocina CCL20/biosíntesis , Quimiocina CCL8/biosíntesis , Quimiocinas/metabolismo , Folículo Piloso/metabolismo , Humanos , Queratinocitos/metabolismo , Células de Langerhans/inmunología , Ratones , Ratones Pelados , Receptores CCR2/metabolismo , Receptores CCR6/metabolismo , Receptores CCR8/metabolismo , Piel/inmunología
13.
Plant Physiol ; 193(2): 966-979, 2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37265110

RESUMEN

There is a limited understanding of the carbon assimilation capacity of nonfoliar green tissues and its impact on yield and seed quality since most photosynthesis research focuses on leaf photosynthesis. In this study, we investigate the photosynthetic efficiency of soybean (Glycine max) pods and seeds in a field setting and evaluate its effect on mature seed weight and composition. We demonstrate that soybean pod and seed photosynthesis contributes 13% to 14% of the mature seed weight. Carbon assimilation by soybean pod and seed photosynthesis can compensate for 81% of carbon loss through the respiration of the same tissues, and our model predicts that soybean pod and seed photosynthesis contributes up to 9% of the total daily carbon gain of the canopy. Chlorophyll fluorescence (CF) shows that the operating efficiency of photosystem II in immature soybean seeds peaks at the 10 to 100 mg seed weight stage, while that of immature pods peaks at the 75 to 100 mg stage. This study provides quantitative information about the efficiency of soybean pod and seed photosynthesis during tissue development and its impact on yield.


Asunto(s)
Carbono , Glycine max , Fotosíntesis , Hojas de la Planta , Semillas
14.
Ann Surg Oncol ; 31(2): 1336-1346, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37991581

RESUMEN

BACKGROUND: In this era of increasing neoadjuvant chemotherapy, methods for evaluating responses to neoadjuvant chemotherapy are still diverse among institutions. Additionally, the efficacy of adjuvant chemotherapy for patients undergoing neoadjuvant chemotherapy remains unclear. Therefore, this retrospective study was performed to evaluate the effectiveness of methods for assessing response to neoadjuvant chemotherapy and the need for adjuvant chemotherapy in treating patients with non-metastatic pancreatic ductal adenocarcinoma. METHODS: The study identified 150 patients who underwent neoadjuvant FOLFIRINOX chemotherapy followed by curative-intent pancreatectomy. The patients were stratified by biochemical response based on the normalization of carbohydrate antigen 19-9 and by radiologic response based on size change at imaging. RESULTS: The patients were classified into the following three groups based on their response to neoadjuvant chemotherapy and prognosis: biochemical responders (BR+), radiology-only responders (BR-/RR+), and non-responders (BR-/RR-). The 3-year overall survival rate was higher for BR+ (71.0%) than for BR-/RR+ (53.6%) or BR-/RR- (33.1%) (P < 0.001). Response to neoadjuvant chemotherapy also was identified as a significant risk factor for recurrence in a comparison between BR-/RR+ and BR+ (hazard ratio [HR], 2.15; 95% confidence interval [CI] 1.19-3.88; P = 0.011) and BR-/RR- (HR, 3.82; 95% CI 2.41-6.08; P < 0.001). Additionally, regardless of the response to neoadjuvant chemotherapy, patients who completed adjuvant chemotherapy had a significantly higher 3-year overall survival rate than those who did not. CONCLUSIONS: This response evaluation criterion for neoadjuvant chemotherapy is feasible and can significantly predict prognosis. Additionally, completion of adjuvant chemotherapy could be helpful to patients who undergo neoadjuvant chemotherapy regardless of their response to neoadjuvant chemotherapy.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Radiología , Humanos , Neoplasias Pancreáticas/cirugía , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Neoadyuvante , Estudios Retrospectivos , Fluorouracilo , Carcinoma Ductal Pancreático/cirugía , Pronóstico , Pancreatectomía/métodos
15.
Cancer Cell Int ; 24(1): 43, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273381

RESUMEN

BACKGROUND: The FGF/FGFR signaling pathway plays a critical role in human cancers. We analyzed the anti-tumor effect of AZD4547, an inhibitor targeting the FGF/FGFR pathway, in epithelial ovarian cancer (EOC) and strategies on overcoming AZD4547 resistance. METHODS: The effect of AZD4547 on cell viability/migration was evaluated and in vivo experiments in intraperitoneal xenografts using EOC cells and a patient-derived xenograft (PDX) model were performed. The effect of the combination of AZD4547 with SU11274, a c-Met-specific inhibitor, FGF19-specific siRNA, or an FGFR4 inhibitor was evaluated by MTT assay. RESULTS: AZD4547 significantly decreased cell survival and migration in drug-sensitive EOC cells but not drug-resistant cells. AZD4547 significantly decreased tumor weight in xenograft models of drug-sensitive A2780 and SKOV3ip1 cells and in a PDX with drug sensitivity but not in models with drug-resistant A2780-CP20 and SKOV3-TR cells. Furthermore, c-Met expression was high in SKOV3-TR and HeyA8-MDR cells, and co-administration of SU11274 and AZD4547 synergistically induced cell death. In addition, expressions of FGF19 and FGFR4 were high in A2780-CP20 cells. Combining AZD4547 with FGF19 siRNA or with a selective FGFR4 inhibitor led to significantly reduced cell proliferation in A2780-CP20 cells. CONCLUSIONS: This study showed that AZD4547 has significant anti-cancer effects in drug-sensitive cells and PDX models but not in drug-resistant EOC cells. In drug-resistant cells, the expression level of c-Met or FGF19/FGFR4 may be a predictive biomarker for AZD4547 treatment response, and a combination strategy of drugs targeting c-Met or FGF19/FGFR4 together with AZD4547 may be an effective therapeutic strategy for EOC.

16.
BMC Cancer ; 24(1): 866, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39026289

RESUMEN

BACKGROUND: The identification of viable tumors and radiation necrosis after stereotactic radiosurgery (SRS) is crucial for patient management. Tumor habitat analysis involving the grouping of similar voxels can identify subregions that share common biology and enable the depiction of areas of tumor recurrence and treatment-induced change. This study aims to validate an imaging biomarker for tumor recurrence after SRS for brain metastasis by conducting tumor habitat analysis using multi-parametric MRI. METHODS: In this prospective study (NCT05868928), patients with brain metastases will undergo multi-parametric MRI before SRS, and then follow-up MRIs will be conducted every 3 months until 24 months after SRS. The multi-parametric MRI protocol will include T2-weighted and contrast-enhanced T1-weighted imaging, diffusion-weighted imaging, and dynamic susceptibility contrast imaging. Using k-means voxel-wise clustering, this study will define three structural MRI habitats (enhancing, solid low-enhancing, and nonviable) on T1- and T2-weighted images and three physiologic MRI habitats (hypervascular cellular, hypovascular cellular, and nonviable) on apparent diffusion coefficient maps and cerebral blood volume maps. Using RANO-BM criteria as the reference standard, via Cox proportional hazards analysis, the study will prospectively evaluate associations between parameters of the tumor habitats and the time to recurrence. The DICE similarity coefficients between the recurrence site and tumor habitats will be calculated. DISCUSSION: The tumor habitat analysis will provide an objective and reliable measure for assessing tumor recurrence from brain metastasis following SRS. By identifying subregions for local recurrence, our study could guide the next therapeutic targets for patients after SRS. TRIAL REGISTRATION: This study is registered at ClinicalTrials.gov (NCT05868928).


Asunto(s)
Neoplasias Encefálicas , Recurrencia Local de Neoplasia , Radiocirugia , Humanos , Radiocirugia/métodos , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Neoplasias Encefálicas/radioterapia , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Estudios Prospectivos , Femenino , Masculino , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Adulto , Anciano , Medición de Riesgo/métodos
17.
Psychol Med ; 54(5): 847-873, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38173096

RESUMEN

The reading the mind in the eyes test (RMET) - which assesses the theory of mind component of social cognition - is often used to compare social cognition between patients with schizophrenia and healthy controls. There is, however, no systematic review integrating the results of these studies. We identified 198 studies published before July 2020 that administered RMET to patients with schizophrenia or healthy controls from three English-language and two Chinese-language databases. These studies included 41 separate samples of patients with schizophrenia (total n = 1836) and 197 separate samples of healthy controls (total n = 23 675). The pooled RMET score was 19.76 (95% CI 18.91-20.60) in patients and 25.53 (95% CI 25.19-25.87) in controls (z = 12.41, p < 0.001). After excluding small-sample outlier studies, this difference in RMET performance was greater in studies using non-English v. English versions of RMET (Chi [Q] = 8.54, p < 0.001). Meta-regression analyses found a negative association of age with RMET score and a positive association of years of schooling with RMET score in both patients and controls. A secondary meta-analysis using a spline construction of 180 healthy control samples identified a non-monotonic relationship between age and RMET score - RMET scores increased with age before 31 and decreased with age after 31. These results indicate that patients with schizophrenia have substantial deficits in theory of mind compared with healthy controls, supporting the construct validity of RMET as a measure of social cognition. The different results for English versus non-English versions of RMET and the non-monotonic relationship between age and RMET score highlight the importance of the language of administration of RMET and the possibility that the relationship of aging with theory of mind is different from the relationship of aging with other types of cognitive functioning.

18.
Pancreatology ; 24(3): 463-488, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38480047

RESUMEN

BACKGROUND: The management of branch-duct type intraductal papillary mucinous neoplasms (BD-IPMN) varies in existing guidelines. This study investigated the optimal surveillance protocol and safe discontinuation of surveillance considering natural history in non-resected IPMN, by systematically reviewing the published literature. METHODS: This review was guided by PRISMA. Research questions were framed in PICO format "CQ1-1: Is size criteria helpful to determine surveillance period? CQ1-2: How often should surveillance be carried out? CQ1-3: When should surveillance be discontinued? CQ1-4: Is nomogram predicting malignancy useful during surveillance?". PubMed was searched from January-April 2022. RESULTS: The search generated 2373 citations. After screening, 83 articles were included. Among them, 33 studies were identified for CQ1-1, 19 for CQ1-2, 26 for CQ1-3 and 12 for CQ1-4. Cysts <1.5 or 2 cm without worrisome features (WF) were described as more indolent, and most studies advised an initial period of surveillance. The median growth rate of cysts <2 cm ranged from 0.23 to 0.6 mm/year. Patients with cysts <2 cm showing no morphological changes and no WF after 5-years of surveillance have minimal malignancy risk of 0-2%. Two nomograms created with over 1000 patients had AUCs of around 0.8 and appear to be feasible in a real-world practice. CONCLUSIONS: For patients with suspected BD-IPMN <2 cm and no other WF, less frequent surveillance is recommended. Surveillance may be discontinued for cysts that remain stable during 5-year surveillance, with consideration of patient condition and life expectancy. With this updated surveillance strategy, patients with non-worrisome BD-IPMN should expect more streamlined management and decreased healthcare utilization.

19.
Endoscopy ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38718833

RESUMEN

BACKGROUND: Disposable digital single-operator cholangioscopy (D-SOC) and direct peroral cholangioscopy (D-POC) using an ultraslim endoscope are established POC modalities for the diagnosis and treatment of various biliary diseases. We compared the usefulness of D-SOC and D-POC for the diagnosis of intraductal superficial lesions of the bile duct (ISL-Bs). METHODS: 38 consecutive patients with suspected biliary diseases who underwent both D-SOC and D-POC were enrolled. The primary outcome was ISL-B detection rate, and the secondary outcomes were technical success of POC and POC-guided forceps biopsy sampling (POC-FB), procedure time, visualization quality, and tissue adequacy. RESULTS: D-SOC had a higher technical success rate than D-POC but the difference was not statistically significant (100% vs. 92.1%, P = 0.25). D-POC had a marginally higher ISL-B detection rate (34.2% vs. 28.9%, P = 0.68) and significantly higher visualization quality (P = 0.03). The mean (SD) procedure time was significantly shorter with D-SOC (11.00 [1.33] vs. 19.03 [2.95] minutes, P<0.001). The technical success rate of POC-FB and tissue adequacy did not differ between the two techniques (D-SOC vs. D-POC: 81.8% vs. 84.6%, P = 0.69 and 77.8% vs. 90.9%, P = 0.57, respectively). CONCLUSIONS: Both POC systems were safe and useful for the detection, characterization, and diagnosis of minute ISL-Bs. While D-SOC displayed a shorter procedure time and a tendency for higher technical success rate, D-POC provided superior visualization quality, allowing detailed observation of the surface structure and microvascular patterns.

20.
Gynecol Oncol ; 188: 60-70, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38936282

RESUMEN

OBJECTIVE: Ovarian cancer, a leading cause of cancer-related deaths in women, remains a formidable challenge, especially in the context of platinum-resistant disease. This study investigated the potential of the benzimidazole derivative BNZ-111 as a novel treatment strategy for platinum-resistant ovarian cancer. METHODS: The human EOC cell lines A2780, HeyA8, SKOV3ip1, A2780-CP20, HeyA8-MDR, and SKOV3-TR were treated with BNZ-111, and cell proliferation, apoptosis, and cell cycle were assessed. RESULTS: It demonstrated strong cytotoxicity in both chemo-sensitive and chemo-resistant epithelial ovarian cancer cell lines, inducing apoptosis and G2/M cell cycle arrest. In vivo experiments using orthotopic and patient-derived xenograft models showed significant tumor growth inhibition without apparent toxicity to vital organs. Unlike paclitaxel, BNZ-111 proved effective in paclitaxel-resistant cells, potentially by bypassing interaction with MDR1 and modulating ß-3 tubulin expression to suppress microtubule dynamics. CONCLUSION: BNZ-111, with favorable drug-like properties, holds promise as a therapeutic option for platinum-resistant ovarian cancer, addressing a critical clinical need in gynecologic oncology.

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