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2.
Sci Adv ; 10(33): eado2585, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39150999

RESUMEN

Transitions in eruptive style during volcanic eruptions strongly depend on how easily gas and magma decouple during ascent. Stronger gas-melt coupling favors highly explosive eruptions, whereas weaker coupling promotes lava fountaining and lava flows. The mechanisms producing these transitions are still poorly understood because of a lack of direct observations of bubble dynamics under natural magmatic conditions. Here, we combine x-ray radiography with a novel high-pressure/high-temperature apparatus to observe and quantify in real-time bubble growth and coalescence in basaltic magmas from 100 megapascals to surface. For low-viscosity magmas, bubbles coalesce and recover a spherical shape within 3 seconds, implying that, for lava fountaining activity, gas and melt remain coupled during the ascent up to the last hundred meters of the conduit. For higher-viscosity magmas, recovery times become longer, promoting connected bubble pathways. This apparatus opens frontiers in unraveling magmatic/volcanic processes, leading to improved hazard assessment and risk mitigation.

3.
Brachytherapy ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39174358

RESUMEN

OBJECTIVE: We utilized the National Cancer Database (NCDB) to evaluate trends and assess outcomes in radiation therapy (RT) boost modality and total dose among medically inoperable endometrial cancer (EC) patients with locoregional disease. METHODS: Patients with International Federation of Gynecology and Obstetrics (FIGO) stage I - IIIC2 inoperable EC treated with RT ± chemotherapy were analyzed. Practice patterns compared external beam RT (EBRT) versus high-dose-rate brachytherapy (BT) boost and total RT dose (palliative: ≤3000 cGy, definitive low dose [DLD]: 4500 - 6249 cGy, definitive high dose [DHD]: ≥6250 cGy) over time. Kaplan-Meier method evaluated overall survival (OS) and Cox proportional hazard modeling assessed variables associated with OS. RESULTS: NCDB included 1755 total cases, of which 1209 received a radiotherapy boost. From 2004 to 2019, boost modality rates differed with increasing utilization of BT consolidation and a decreasing rate of palliation. Predictors of a palliative dose were stage III disease, Black race, N2 disease, and poorly or undifferentiated grade. Multivariable analysis found BT boost was associated with lower mortality compared to EBRT (HR: 0.81, CI: 0.68-0.97; p = 0.019). Mortality rates were higher for palliation versus DHD. Additional factors associated with inferior survival were increasing age, worse Charlson-Deyo score, higher T stage, higher N stage, and moderately, poorly, or undifferentiated grade. CONCLUSIONS: Utilization of BT boost for locoregionally confined, medically inoperable EC has increased since 2004. Brachytherapy consolidation remains an effective RT modality for medically inoperable EC, associated with lower mortality compared to EBRT consolidation.

4.
PLoS One ; 19(8): e0307076, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39172977

RESUMEN

BACKGROUND/OBJECTIVES: Germline genetic testing is recommended for younger patients with idiopathic pancreatitis but there has been a lack of consensus in recommendations for those over age 35. We aimed to analyze the results of genetic testing among subjects of varying ages. METHODS: Individuals who underwent germline multigene testing for pancreatitis susceptibility genes (CASR, CFTR, CPA1, CTRC, PRSS1, SPINK1) through a large commercial laboratory between 2017 and 2022 were included. Test results and information collected from test requisition forms were evaluated. Multivariable logistic regression models were performed to identify factors associated with a positive pancreatitis panel (pathogenic, likely pathogenic, and/or increased risk variants) in pancreatitis-related genes. RESULTS: Overall, 2,468 subjects with primary indication of acute pancreatitis (AP) (n = 401), chronic pancreatitis (CP) (n = 631), pancreatic cancer (n = 128), or other indications (n = 1,308) completed germline testing. Among patients with AP or CP, the prevalence of any positive result for those <35 versus ≥35 years of age was 32.1% and 24.5% (p = 0.007), and the prevalence of a clinically meaningful result was 10.8% and 5.4%, respectively (p = 0.001). Positive family history of pancreatitis was associated with increased odds ratio (OR) of 8.59 (95% confidence interval (CI) 2.92-25.25) for a clinically significant panel result while each 5-year increase in age at test completion had lower odds (OR 0.89, 95% CI 0.83-0.95). CONCLUSIONS: The highest prevalence of pathogenic variants is seen in younger individuals with a positive family history of pancreatitis. However, clinically meaningful results are identified in older subjects, suggesting that genetic counseling and testing should be considered for all age groups.


Asunto(s)
Predisposición Genética a la Enfermedad , Pruebas Genéticas , Mutación de Línea Germinal , Pancreatitis Crónica , Humanos , Adulto , Femenino , Masculino , Pruebas Genéticas/métodos , Persona de Mediana Edad , Pancreatitis Crónica/genética , Pancreatitis Crónica/diagnóstico , Anciano , Pancreatitis/genética , Pancreatitis/diagnóstico , Adulto Joven , Adolescente , Enfermedad Aguda , Niño
6.
Cancer Immunol Res ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39051632

RESUMEN

Immune composition within the tumor microenvironment (TME) plays a central role in the propensity of cancer to metastasize and to respond to therapy. Previous studies suggested that the metastatic TME is immune suppressed. However, limited accessibility to multiple metastatic sites within patients has made assessment of the immune TME in the context of multi-organ metastases difficult. We utilized a rapid postmortem tissue collection protocol to assess immune composition in numerous sites of breast cancer metastasis and paired tumor-free tissues. Metastases were found to have comparable immune cell densities and composition to paired tumor-free tissues of the same organ type. In contrast, immune cell densities in both metastatic and tumor-free tissues were significantly different between organ types, with lung immune infiltration consistently greater than liver. These immune profiling results were consistent between both flow cytometry and multiplex immunofluorescence-based spatial analysis. Furthermore, we found granulocytes were a predominant tumor-infiltrating immune cell in both lung and liver metastases and these granulocytes made up the majority of PD-L1-expressing cells in many tissue sites. We also identified distinct potential mechanisms of immunosuppression in lung and liver metastases, with lung having increased expression of PD-L1+ antigen-presenting cells and liver having higher numbers of activated regulatory T cells and HLA-DRlow monocytes. Together these results demonstrate that immune contexture of metastases is dictated by organ type, and that immunotherapy strategies may benefit from unique tailoring to tissue-specific features of the immune TME.

7.
Arch Sex Behav ; 53(8): 2939-2956, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39039338

RESUMEN

Clinical decision-making for individuals with 46,XY disorders/differences of sex development (DSD) remains unsettled and controversial. The North American DSD Clinician Survey examines the recommendations of a large group of clinical specialists over the last two decades. Active members of the (Lawson Wilkins) Pediatric Endocrine Society and the Societies for Pediatric Urology were invited to respond to a web-based survey at three different timepoints: 2003-2004 (T1), 2010-2011 (T2), and 2019-2020 (T3). Data from 429 participants in T1, 435 in T2, and 264 in T3 were included in this study. The participants were presented with three XY newborn clinical case scenarios-micropenis, partial androgen insensitivity syndrome, and iatrogenic penile ablation-and asked for clinical management recommendations. The main outcomes assessed included the recommended gender of rearing, surgical decision-maker (parent or patient), timing of genital surgery, and age at which to disclose medical details and surgical history to the patient. For all scenarios, the overwhelming majority recommended rearing as male, including a significant increase across timepoints in those recommending a male gender of rearing for the infant with penile ablation. The proportions recommending female gender of rearing declined significantly across timepoints. In general, most recommended parents (in consultation with the physician) serve as surgical decision-makers, but these proportions declined significantly across timepoints. Recommendations on the timing of surgery varied based on the patient's gender and type of surgery. There has been a shift in recommendations away from the "optimal gender policy" regarding gender of rearing and surgical interventions for patients with XY DSD.


Asunto(s)
Trastorno del Desarrollo Sexual 46,XY , Humanos , Masculino , Femenino , Endocrinólogos , Urólogos , América del Norte , Recién Nacido , Toma de Decisiones Clínicas , Adulto , Pautas de la Práctica en Medicina/estadística & datos numéricos , Encuestas y Cuestionarios , Niño
8.
Curr Opin Gastroenterol ; 40(5): 389-395, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38967941

RESUMEN

PURPOSE OF REVIEW: Acute pancreatitis is a common acute inflammatory disorder of the pancreas, and its incidence has been increasing worldwide. Approximately 10% of acute pancreatitis progresses to severe acute pancreatitis (SAP), which carries significant morbidity and mortality. Disordered immune response to pancreatic injury is regarded as a key event that mediates systemic injury in SAP. In this article, we review recent developments in immune biomarkers of SAP and future directions for research. RECENT FINDINGS: Given the importance of the NLRP3-inflammasome pathway in mediating systemic inflammatory response syndrome and systemic injury, recent studies have investigated associations of SAP with systemic levels of activators of NLRP3, such as the damage associated molecular patterns (DAMPs) for the first time in human SAP. For example, circulating levels of histones, mitochondrial DNAs, and cell free DNAs have been associated with SAP. A panel of mechanistically relevant immune markers (e.g., panel of Angiopoeitin-2, hepatocyte growth factor, interleukin-8 (IL-8), resistin and sTNF-α R1) carried higher predictive accuracies than existing clinical scores and individual immune markers. Of the cytokines with established relevance to SAP pathogenesis, phase 2 trials of immunotherapies, including tumor necrosis factor (TNF)-alpha inhibition and stimulation of IL-10 production, are underway to determine if altering the immunologic response can reduce the severity of acute pancreatitis (AP). SUMMARY: Circulating systemic levels of various DAMPs and a panel of immune markers that possibly reflect activities of different pathways that drive SAP appear promising as predictive biomarkers for SAP. But larger multicenter studies are needed for external validation. Studies investigating immune cellular pathways driving SAP using immunophenotyping techniques are scarce. Interdisciplinary efforts are also needed to bring some of the promising biomarkers to the bedside for validation and testing for clinical utility. Studies investigating the role of and characterization of altered gut-lymph and gut-microbiota in severe AP are needed.


Asunto(s)
Biomarcadores , Pancreatitis , Humanos , Biomarcadores/sangre , Pancreatitis/inmunología , Pancreatitis/sangre , Pancreatitis/diagnóstico , Citocinas/sangre , Citocinas/inmunología , Índice de Severidad de la Enfermedad , Enfermedad Aguda , Inflamasomas/inmunología
9.
Value Health ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38977195

RESUMEN

OBJECTIVES: To accurately capture informal care in healthcare evaluations, rigorous approaches are required to measure and value this important care component. In this systematic review and meta-analysis, we intended to summarize the current methods of measuring and valuing informal care costs in healthcare evaluations (full and partial healthcare evaluations, including cost of illness and cost analysis) in stroke. METHODS: A systematic search was conducted in MEDLINE, Embase, EconLit, and CINAHL. We used EndNote 20, Research Screener, and Covidence platforms for screening and data extraction. A meta-analysis was performed on informal care hours, and a subgroup meta-analysis was conducted based on stroke severity. RESULTS: A total of 31 articles were included in the qualitative synthesis. There was variation among the studies in the informal care measurement and valuation approaches. The meta-analysis of studies where data on informal care hours were available showed an estimate of informal care hours of 25.76 per week (95% CI 13.36-38.16) with a high heterogeneity (I2 = 99.97%). The overall risk of bias in the studies was assessed as low. CONCLUSIONS: Standardizing the measurement and valuation of informal care costs is essential for improving the consistency and comparability of economic evaluations. Pilot studies that incorporate standardized informal care cost valuation methods can help identify any practical challenges and capture the impact of informal care more accurately.

10.
Res Sq ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39070623

RESUMEN

Automated blood vessel segmentation is critical for biomedical image analysis, as vessel morphology changes are associated with numerous pathologies. Still, precise segmentation is difficult due to the complexity of vascular structures, anatomical variations across patients, the scarcity of annotated public datasets, and the quality of images. Our goal is to provide a foundation on the topic and identify a robust baseline model for application to vascular segmentation using a new imaging modality, Hierarchical Phase-Contrast Tomography (HiP-CT). We begin with an extensive review of current machine learning approaches for vascular segmentation across various organs. Our work introduces a meticulously curated training dataset, verified by double annotators, consisting of vascular data from three kidneys imaged using Hierarchical Phase-Contrast Tomography (HiP-CT) as part of the Human Organ Atlas Project. HiP-CT, pioneered at the European Synchrotron Radiation Facility in 2020, revolutionizes 3D organ imaging by offering resolution around 20µm/voxel, and enabling highly detailed localized zooms up to 1µm/voxel without physical sectioning. We leverage the nnU-Net framework to evaluate model performance on this high-resolution dataset, using both known and novel samples, and implementing metrics tailored for vascular structures. Our comprehensive review and empirical analysis on HiP-CT data sets a new standard for evaluating machine learning models in high-resolution organ imaging. Our three experiments yielded Dice scores of 0.9523 and 0.9410, and 0.8585, respectively. Nevertheless, DSC primarily assesses voxel-to-voxel concordance, overlooking several crucial characteristics of the vessels and should not be the sole metric for deciding the performance of vascular segmentation. Our results show that while segmentations yielded reasonably high scores-such as centerline Dice values ranging from 0.82 to 0.88, certain errors persisted. Specifically, large vessels that collapsed due to the lack of hydro-static pressure (HiP-CT is an ex vivo technique) were segmented poorly. Moreover, decreased connectivity in finer vessels and higher segmentation errors at vessel boundaries were observed. Such errors, particularly in significant vessels, obstruct the understanding of the structures by interrupting vascular tree connectivity. Through our review and outputs, we aim to set a benchmark for subsequent model evaluations using various modalities, especially with the HiP-CT imaging database.

11.
Radiology ; 312(1): e232731, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-39012246

RESUMEN

Background Current clinical imaging modalities such as CT and MRI provide resolution adequate to diagnose cardiovascular diseases but cannot depict detailed structural features in the heart across length scales. Hierarchical phase-contrast tomography (HiP-CT) uses fourth-generation synchrotron sources with improved x-ray brilliance and high energies to provide micron-resolution imaging of intact adult organs with unprecedented detail. Purpose To evaluate the capability of HiP-CT to depict the macro- to microanatomy of structurally normal and abnormal adult human hearts ex vivo. Materials and Methods Between February 2021 and September 2023, two adult human donor hearts were obtained, fixed in formalin, and prepared using a mixture of crushed agar in a 70% ethanol solution. One heart was from a 63-year-old White male without known cardiac disease, and the other was from an 87-year-old White female with a history of multiple known cardiovascular pathologies including ischemic heart disease, hypertension, and atrial fibrillation. Nondestructive ex vivo imaging of these hearts without exogenous contrast agent was performed using HiP-CT at the European Synchrotron Radiation Facility. Results HiP-CT demonstrated the capacity for high-spatial-resolution, multiscale cardiac imaging ex vivo, revealing histologic-level detail of the myocardium, valves, coronary arteries, and cardiac conduction system across length scales. Virtual sectioning of the cardiac conduction system provided information on fatty infiltration, vascular supply, and pathways between the cardiac nodes and adjacent structures. HiP-CT achieved resolutions ranging from gross (isotropic voxels of approximately 20 µm) to microscopic (approximately 6.4-µm voxel size) to cellular (approximately 2.3-µm voxel size) in scale. The potential for quantitative assessment of features in health and disease was demonstrated. Conclusion HiP-CT provided high-spatial-resolution, three-dimensional images of structurally normal and diseased ex vivo adult human hearts. Whole-heart image volumes were obtained with isotropic voxels of approximately 20 µm, and local regions of interest were obtained with resolution down to 2.3-6.4 µm without the need for sectioning, destructive techniques, or exogenous contrast agents. Published under a CC BY 4.0 license Supplemental material is available for this article. See also the editorial by Bluemke and Pourmorteza in this issue.


Asunto(s)
Corazón , Tomografía Computarizada por Rayos X , Humanos , Persona de Mediana Edad , Masculino , Femenino , Tomografía Computarizada por Rayos X/métodos , Corazón/diagnóstico por imagen , Anciano de 80 o más Años , Cardiopatías/diagnóstico por imagen , Sincrotrones
12.
Brachytherapy ; 23(5): 559-568, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39060143

RESUMEN

PURPOSE: We aim to investigate perioperative and subacute postoperative complications in patients undergoing LDR or HDR monotherapy for prostate cancer. We hypothesize a low rate of complications, and a favorable toxicity profile in patients treated with HDR compared to LDR. MATERIALS AND METHODS: A prospectively collected institutional database was queried for patients treated with HDR or LDR prostate monotherapy between 1998 and 2021. Toxicities were determined per CTCAE. Claims based billing codes were obtained to identify additional events. Events occurring within 4 months of treatment were defined as perioperative or subacute postoperative complications. RESULTS: 759 patients were identified, 446 received LDR with 125I, and 313 received HDR with 192Ir. HDR patients had higher risk features: 75.7% with Gleason score 7+ versus 2.4% of LDR, and 16% with initial PSA 10+ ng/mL versus 2.7% of LDR. Toxicities were mild with the most common being grade 1 GU frequency and nocturia at ∼50%. HDR patients had significantly less grade 2 dysuria (2.6% vs. 9.0%), frequency (4.8% vs. 9.4%), hematuria (1.0% vs. 5.2%), nocturia (3.8% vs. 9.4%), and urinary obstructive symptoms (7.3% vs. 11.2%), all statistically significant. 11 (1.4%) patients had infection requiring antibiotics: 8 (1.8%) from the LDR group and 3 (1%) from the HDR group. Cardiopulmonary events were low at <2% overall, without difference between HDR and LDR. CONCLUSIONS: Overall toxicity rates support the safety of prostate brachytherapy. HDR monotherapy is associated with significantly less perioperative and subacute postoperative GU events when compared to LDR monotherapy. Cardiopulmonary events were equally rare in both groups.


Asunto(s)
Braquiterapia , Complicaciones Posoperatorias , Neoplasias de la Próstata , Humanos , Masculino , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/cirugía , Braquiterapia/efectos adversos , Anciano , Complicaciones Posoperatorias/epidemiología , Persona de Mediana Edad , Radioisótopos de Yodo/uso terapéutico , Radioisótopos de Yodo/efectos adversos , Estudios Prospectivos
14.
Adv Sci (Weinh) ; : e2406309, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39076120

RESUMEN

Frequent recurrence and metastasis caused by cancer stem cells (CSCs) are major challenges in lung cancer treatment. Therefore, identifying and characterizing specific CSC targets are crucial for the success of prospective targeted therapies. In this study, it is found that upregulated TOR Signaling Pathway Regulator-Like (TIPRL) in lung CSCs causes sustained activation of the calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) signaling pathway by binding to CaMKK2, thereby maintaining stemness and survival. CaMKK2-mediated activation of CaM kinase 4 (CaMK4) leads to phosphorylation of cAMP response element-binding protein (CREB) at Ser129 and Ser133, which is necessary for its maximum activation and the downstream constitutive expression of its target genes (Bcl2 and HMG20A). TIPRL depletion sensitizes lung CSCs to afatinib-induced cell death and reduces distal metastasis of lung cancer in vivo. It is determined that CREB activates the transcription of TIPRL in lung CSCs. The positive feedback loop consisting of CREB and TIPRL induces the sustained activation of the CaMKK2-CaMK4-CREB axis as a driving force and upregulates the expression of stemness- and survival-related genes, promoting tumorigenesis in patients with lung cancer. Thus, TIPRL and the CaMKK2 signaling axis may be promising targets for overcoming drug resistance and reducing metastasis in lung cancer.

15.
BMJ Open ; 14(7): e073740, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39043600

RESUMEN

OBJECTIVES: We sought to extrapolate the long-term costs and clinical impacts attributed to the rugby fans in training-New Zealand (RUFIT-NZ) trial in Aotearoa, New Zealand. DESIGN: A modelled cost-effectiveness analysis using efficacy data from RUFIT-NZ was conducted from the Aotearoa New Zealand healthcare perspective. SETTING: A Markov cohort model was constructed with a lifetime time horizon. The model simulated events of myocardial infarction (MI), stroke and type 2 diabetes mellitus (T2DM) occurring among a hypothetical cohort of 10 000 individuals receiving either the RUFIT-NZ intervention or no intervention. Efficacy data were based on the RUFIT-NZ trial, and the latest Global Burden of Disease study was used to extrapolate the impact of body weight reduction on clinical outcomes of T2DM, MI or stroke. Cost and utility data were drawn from the RUFIT-NZ trial and published sources. PRIMARY OUTCOME MEASURES: The incremental cost-effectiveness ratio (ICER). RESULTS: Over a lifetime time horizon, participants in the RUFIT-NZ intervention gained 0.02 (discounted) quality-adjusted life years (QALYs) at an additional cost of NZ$863, relative to no intervention. The estimated ICER was NZ$49 515 per QALY gained (discounted), which is above the arbitrary willingness-to-pay threshold of NZ$45 000 per QALY. Sensitivity analyses supported the robustness of these findings. CONCLUSIONS: RUFIT-NZ was associated with a reduction in cardiovascular and endocrine events for overweight and obese males. However, based on conservative assumptions, RUFIT-NZ was unlikely to be cost-effective from a healthcare system perspective. TRIAL REGISTRATION NUMBER: ACTRN12619000069156.


Asunto(s)
Análisis Costo-Beneficio , Diabetes Mellitus Tipo 2 , Cadenas de Markov , Años de Vida Ajustados por Calidad de Vida , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad , Análisis de Costo-Efectividad , Diabetes Mellitus Tipo 2/economía , Infarto del Miocardio/prevención & control , Nueva Zelanda , Accidente Cerebrovascular/prevención & control , Pérdida de Peso , Programas de Reducción de Peso/economía , Programas de Reducción de Peso/métodos , Rugby
16.
J Biomech ; 172: 112178, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38959820

RESUMEN

Reactive lower limb muscle function during walking plays a key role in balance recovery following tripping, and ultimately fall prevention. The objective of this study was to evaluate muscle and joint function in the recovery limb during balance recovery after trip-based perturbations during walking. Twenty-four healthy participants underwent gait analysis while walking at slow, moderate and fast speeds over level, uphill and downhill inclines. Trip perturbations were performed randomly during stance, and lower limb kinematics, kinetics, and muscle contribution to the acceleration of the whole-body centre of mass (COM) were computed pre- and post-perturbation in the recovery limb. Ground slope and walking speed had a significant effect on lower limb joint angles, net joint moments and muscle contributions to support and propulsion during trip recovery (p < 0.05). Specifically, increasing walking speed during trip recovery significantly reduced hip extension in the recovery limb and increased knee flexion, particularly when walking uphill and at higher walking speeds (p < 0.05). Gluteus maximus played a critical role in providing support and forward propulsion of the body during trip recovery across all gait speeds and ground inclinations. This study provides a mechanistic link between muscle action, joint motion and COM acceleration during trip recovery, and underscores the potential of increased walking speed and ground inclination to increase fall risk, particularly in individuals prone to falling. The findings of this study may provide guidelines for targeted exercise therapy such as muscle strengthening for fall prevention.


Asunto(s)
Accidentes por Caídas , Marcha , Músculo Esquelético , Equilibrio Postural , Velocidad al Caminar , Humanos , Masculino , Femenino , Equilibrio Postural/fisiología , Músculo Esquelético/fisiología , Velocidad al Caminar/fisiología , Marcha/fisiología , Adulto , Accidentes por Caídas/prevención & control , Fenómenos Biomecánicos , Caminata/fisiología , Articulación de la Rodilla/fisiología , Articulación de la Cadera/fisiología
17.
J Control Release ; 373: 105-116, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38992622

RESUMEN

Nanomedicines hold promise for the treatment of various diseases. However, treating cancer metastasis remains highly challenging. In this study, we synthesized gold nanorods (AuNRs) containing (α-GC), an immune stimulator, for the treatment of primary cancer, metastasis, and recurrence of the cancer. Therefore, the AuNR were coated with lipid bilayers loaded with α-GC (α-LA). Upon irradiation with 808 nm light, α-LA showed a temperature increase. Intra-tumoral injection of α-LA in mice and local irradiation of the 4T1 breast cancer tumor effectively eliminated tumor growth. We found that the presence of α-GC in α-LA activated dendritic cells and T cells in the spleen, which completely blocked the development of lung metastasis. In mice injected with α-LA for primary breast cancer treatment, we observed antigen-specific T cell responses and increased cytotoxicity against 4T1 cells. We conclude that α-LA is promising for the treatment of both primary breast cancer and its metastasis.

18.
J Am Chem Soc ; 146(29): 20080-20085, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39001844

RESUMEN

The utility of antibody therapeutics is hampered by potential cross-reactivity with healthy tissue. Over the past decade, significant advances have been made in the design of activatable antibodies, which increase, or create altogether, the therapeutic window of a parent antibody. Of these, antibody prodrugs (pro-antibodies) are masked antibodies that have advanced the most for therapeutic use. They are designed to reveal the active, parent antibody only when encountering proteases upregulated in the microenvironment of the targeted disease tissue, thereby minimizing off-target activity. However, current pro-antibody designs are relegated to fusion proteins that append masking groups restricted to the use of only canonical amino acids, offering excellent control of the site of introduction, but with no authority over where the masking group is installed other than the N-terminus of the antibody. Here, we present a palladium-based bioconjugation approach for the site-specific introduction of a masked tyrosine mimic in the complementary determining region of the FDA approved antibody therapeutic ipilimumab used as a model system. The approach enables the introduction of a protease cleavable group tethered to noncanonical polymers (polyethylene glycol (PEG)) resulting in 47-fold weaker binding to cells expressing CTLA-4, the target antigen of ipilimumab. Upon exposure to tumor-associated proteases, the masking group is cleaved, unveiling a tyrosine-mimic (dubbed hydroxyphenyl cysteine (HPC)) that restores (>90% restoration) binding affinity to its target antigen.


Asunto(s)
Profármacos , Tirosina , Profármacos/química , Profármacos/farmacología , Humanos , Tirosina/química , Paladio/química , Estructura Molecular , Inmunoconjugados/química
19.
Front Aging Neurosci ; 16: 1350239, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38915346

RESUMEN

The glucagon-like peptide-1 receptor (GLP-1R) agonists reduce glycated hemoglobin in patients with type 2 diabetes. Mounting evidence indicates that the potential of GLP-1R agonists, mimicking a 30 amino acid ligand, GLP-1, extends to the treatment of neurodegenerative conditions, with a particular focus on Alzheimer's disease (AD). However, the mechanism that underlies regulation of GLP-1R availability in the brain with AD remains poorly understood. Here, using whole transcriptome RNA-Seq of the human postmortem caudate nucleus with AD and chronic hydrocephalus (CH) in the elderly, we found that GLP-1R and select mRNAs expressed in glucose dysmetabolism and dyslipidemia were significantly altered. Furthermore, we detected human RNA indicating a deficiency in doublecortin (DCX) levels and the presence of ferroptosis in the caudate nucleus impacted by AD. Using the genome data viewer, we assessed mutability of GLP-1R and 39 other genes by two factors associated with high mutation rates in chromosomes of four species. Surprisingly, we identified that nucleotide sizes of GLP-1R transcript exceptionally differed in all four species of humans, chimpanzees, rats, and mice by up to 6-fold. Taken together, the protein network database analysis suggests that reduced GLP-1R in the aged human brain is associated with glucose dysmetabolism, ferroptosis, and reduced DCX+ neurons, that may contribute to AD.

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