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1.
Adv Ther ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261416

RESUMEN

INTRODUCTION: Since direct comparisons of long-acting growth hormones (LAGHs) are lacking, analyses were performed to indirectly compare the efficacy and safety of somapacitan versus somatrogon and lonapegsomatropin in children with growth hormone deficiency (GHD). METHODS: A systematic literature review (SLR) identified studies of once-weekly LAGHs for the treatment of pediatric GHD. Indirect comparisons (ICs) using a Bayesian hierarchical network meta-analysis and a random effects model were performed using daily growth hormone (GH) 0.034 mg/kg/day (base case) or 0.024-0.034 mg/kg/day (alternative analyses) as the common comparator to compare height outcomes to 52 weeks [annualized height velocity, height velocity standard deviation score (SDS), and height SDS]. Identified evidence did not allow IC of safety or longer-term efficacy outcomes so these were qualitatively described. RESULTS: The SLR identified two somapacitan trials, three somatrogon trials (one included in alternative analyses only), and one lonapegsomatropin trial comparing the LAGH with daily GH in treatment-naïve pre-pubertal children for IC. ICs revealed no differences at 52 weeks between somapacitan versus somatrogon and lonapegsomatropin, as well as daily GH, with respect to all growth outcomes considered in children with GHD. All three LAGHs had sustained efficacy and were generally well tolerated, with comparable efficacy and safety to daily GH, with the exception of observed injection site pain for somatrogon. CONCLUSION: No efficacy and safety differences were identified in comparisons of once weekly somapacitan versus somatrogon and lonapegsomatropin, as well as daily GH. All treatments were generally well tolerated, with the exception of observed injection site pain for somatrogon.


It is valuable to compare similarly acting treatments to determine their relative benefits and risks. Direct comparisons of long-acting growth hormones (LAGHs) are lacking, so analyses were performed to indirectly compare the efficacy and safety of the LAGH somapacitan versus the LAGHs somatrogon and lonapegsomatropin in children with growth hormone deficiency. Studies of once-weekly LAGHs for the treatment of pediatric growth hormone deficiency were identified using a systematic literature review, then the data obtained were indirectly compared using standard statistical methods with daily growth hormone 0.034 mg/kg/day (base case) or 0.024­0.034 mg/kg/day (alternative analyses) as the common comparator. Height outcomes to 52 weeks (annualized height velocity, height velocity standard deviation score, and height standard deviation score) were compared between treatments. Sufficient information to allow indirect comparison of safety or longer-term efficacy outcomes were not found so these were qualitatively described. The systematic literature review identified two somapacitan trials, three somatrogon trials (one included in alternative analyses only) and one lonapegsomatropin trial comparing the LAGH with daily growth hormone in previously untreated pre-pubertal children for inclusion in the indirect comparison. Indirect comparisons identified no differences to 52 weeks between somapacitan versus somatrogon and lonapegsomatropin, as well as daily growth hormone, with respect to all growth outcomes considered in children with growth hormone deficiency. All three LAGHs had sustained efficacy and were generally well tolerated, with comparable efficacy and safety to daily growth hormone, with the possible exception of injection site pain with somatrogon.

2.
Elife ; 132024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39248648

RESUMEN

CXCR4 is a ubiquitously expressed chemokine receptor that regulates leukocyte trafficking and arrest in both homeostatic and pathological states. It also participates in organogenesis, HIV-1 infection, and tumor development. Despite the potential therapeutic benefit of CXCR4 antagonists, only one, plerixafor (AMD3100), which blocks the ligand-binding site, has reached the clinic. Recent advances in imaging and biophysical techniques have provided a richer understanding of the membrane organization and dynamics of this receptor. Activation of CXCR4 by CXCL12 reduces the number of CXCR4 monomers/dimers at the cell membrane and increases the formation of large nanoclusters, which are largely immobile and are required for correct cell orientation to chemoattractant gradients. Mechanistically, CXCR4 activation involves a structural motif defined by residues in TMV and TMVI. Using this structural motif as a template, we performed in silico molecular modeling followed by in vitro screening of a small compound library to identify negative allosteric modulators of CXCR4 that do not affect CXCL12 binding. We identified AGR1.137, a small molecule that abolishes CXCL12-mediated receptor nanoclustering and dynamics and blocks the ability of cells to sense CXCL12 gradients both in vitro and in vivo while preserving ligand binding and receptor internalization.


Asunto(s)
Quimiocina CXCL12 , Receptores CXCR4 , Receptores CXCR4/metabolismo , Receptores CXCR4/química , Quimiocina CXCL12/metabolismo , Regulación Alostérica , Humanos , Animales , Unión Proteica , Dominios Proteicos , Modelos Moleculares
3.
J Chem Theory Comput ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105755

RESUMEN

Frozen density embedding (FDE) with freeze-thaw cycles is a formally exact embedding scheme. In practice, this method is limited to systems with small density overlaps when approximate nonadditive kinetic energy functionals are used. It has been shown that the use of approximate nonadditive kinetic energy functionals can be avoided when external orthogonality (EO) is enforced, and FDE can then generate exact results even for strongly overlapping subsystems. In this work, we present an implementation of exact FDEc-EO (coupled FDE TDDFT with EO) for the calculation of polarizabilities in the Amsterdam density functional program package. EO is enforced using the level-shift projection operator method, which ensures that orbitals between fragments are orthogonal. For pure functionals, we show that only the symmetric EO contributions to the induced density matrix are needed. This leads to a simplified implementation for the calculation of polarizability that can exactly reproduce the supermolecular TDDFT results. We further discuss the limitation of exact FDEc-EO in interpreting subsystem polarizabilities due to the nonunique partitioning of the total density. We show that this limitation is due to the fact that subsystem polarizability partitioning is dependent on how the subsystems are initially polarized. As supermolecular virtual orbitals are exactly reproduced, this dependence is attributed to the description of the occupied orbitals. In contrast, for excitations of subsystems that are localized within one subsystem, we show that the excitation energies are stable with respect to the order of polarization. This observation shows that impacts from the nonunique nature of exact FDE on subsystem properties can be minimized by better fragmentation of the supermolecular systems if the property is localized. For global properties like polarizability, this is not the case, and nonuniqueness remains independent of the fragmentation used.

4.
ACS Nano ; 18(32): 20835-20850, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39087679

RESUMEN

Surface-enhanced Raman scattering (SERS) provides detailed information about the binding of molecules at interfaces and their interactions with the local environment due to the large enhancement of Raman scattering. This enhancement arises from a combination of the electromagnetic mechanism (EM) and chemical mechanism (CM). While it is commonly accepted that EM gives rise to most of the enhancement, large spectral changes originate from CM. To elucidate the rich information contained in SERS spectra about molecules at interfaces, a comprehensive understanding of the enhancement mechanisms is necessary. In this Perspective, we discuss the current understanding of the enhancement mechanisms and highlight their interplay in complex local environments. We will also discuss emerging areas where the development of computational and theoretical models is needed with specific attention given to how the CM contributes to the spectral changes. Future efforts in modeling should focus on overcoming the challenges presented in this review in order to capture the complexity of CM in SERS.

5.
World J Surg ; 48(8): 1797-1807, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38886168

RESUMEN

BACKGROUND: Major emergency abdominal surgery is associated with severe postoperative complications and high short- and long-term mortality. Despite recent advancements in standardizing multidisciplinary care bundles, a subgroup of patients continues to face a heightened risk of short-term mortality. This study aimed to identify and describe the high-risk surgical patients and risk factors for short-term postoperative mortality. METHODS: In this study, we included all patients undergoing major emergency abdominal surgery over 2 years and collected data on demographics, intraoperative variables, and short-term outcomes. The primary outcome measure was short-term mortality and secondary outcome measures were pre, intra, and postoperative risk factors for premature death. Multivariable binary regression analysis was performed to determine possible risk factors for short-term mortality. RESULTS: Short-term mortality within 14 days of surgery in this cohort of 754 consecutive patients was 8%. Multivariable analysis identified various independent risk factors for short-term mortality throughout different phases of patient care. These factors included advanced age, preoperative history of myocardial infarction or ischemic heart disease, chronic obstructive pulmonary disease, liver cirrhosis, chronic kidney disease, and vascular bowel ischemia or perforation of the stomach or duodenum during the primary surgery. CONCLUSION: Patients at high risk of early mortality following major emergency abdominal surgery exhibited distinct perioperative risk factors. This study underscores the importance of clinicians identifying and managing these factors in high-risk patients to ensure optimal care.


Asunto(s)
Abdomen , Complicaciones Posoperatorias , Humanos , Femenino , Masculino , Anciano , Persona de Mediana Edad , Factores de Riesgo , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/epidemiología , Abdomen/cirugía , Urgencias Médicas , Anciano de 80 o más Años , Estudios Retrospectivos , Adulto
6.
BMC Public Health ; 24(1): 1280, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730455

RESUMEN

INTRODUCTION: The increasing ageing of the population with growth in NCD burden in India has put unprecedented pressure on India's health care systems. Shortage of skilled human resources in health, particularly of specialists equipped to treat NCDs, is one of the major challenges faced in India. Keeping in view the shortage of healthcare professionals and the guidelines in NEP 2020, there is an urgent need for more health professionals who have received training in the diagnosis, prevention, and treatment of NCDs. This paper conducts a scoping review and aims to collate the existing evidence on the use of digital education of health professionals within NCD topics. METHODS: We searched four databases (Web of Science, PubMed, EBSCO Education Research Complete, and PsycINFO) using a three-element search string with terms related to digital education, health professions, and terms related to NCD. The inclusion criteria covered the studies to be empirical and NCD-related with the target population as health professionals rather than patients. Data was extracted from 28 included studies that reported on empirical research into digital education related to non-communicable diseases in health professionals in India. Data were analysed thematically. RESULTS: The target groups were mostly in-service health professionals, but a considerable number of studies also included pre-service students of medicine (n = 6) and nursing (n = 6). The majority of the studies included imparted online learning as self-study, while some imparted blended learning and online learning with the instructor. While a majority of the studies included were experimental or observational, randomized control trials and evaluations were also part of our study. DISCUSSION: Digital HPE related to NCDs has proven to be beneficial for learners, and simultaneously, offers an effective way to bypass geographical barriers. Despite these positive attributes, digital HPE faces many challenges for its successful implementation in the Indian context. Owing to the multi-lingual and diverse health professional ecosystem in India, there is a need for strong evidence and guidelines based on prior research in the Indian context.


Asunto(s)
Personal de Salud , Enfermedades no Transmisibles , Humanos , Enfermedades no Transmisibles/prevención & control , Enfermedades no Transmisibles/terapia , India , Personal de Salud/educación , Educación a Distancia
7.
BJS Open ; 8(3)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38788680

RESUMEN

BACKGROUND: Major emergency abdominal surgery is associated with a high risk of morbidity and mortality. Given the ageing and increasingly frail population, understanding the impact of frailty on complication patterns after surgery is crucial. The aim of this study was to evaluate the association between clinical frailty and organ-specific postoperative complications after major emergency abdominal surgery. METHODS: A prospective cohort study including all patients undergoing major emergency abdominal surgery at Copenhagen University Hospital Herlev, Denmark, from 1 October 2020 to 1 August 2022, was performed. Clinical frailty scale scores were determined for all patients upon admission and patients were then analysed according to clinical frailty scale groups (scores of 1-3, 4-6, or 7-9). Postoperative complications were registered until discharge. RESULTS: A total of 520 patients were identified. Patients with a low clinical frailty scale score (1-3) experienced fewer total complications (120 complications per 100 patients) compared with patients with clinical frailty scale scores of 4-6 (250 complications per 100 patients) and 7-9 (277 complications per 100 patients) (P < 0.001). A high clinical frailty scale score was associated with a high risk of pneumonia (P = 0.009), delirium (P < 0.001), atrial fibrillation (P = 0.020), and infectious complications in general (P < 0.001). Patients with severe frailty (clinical frailty scale score of 7-9) suffered from more surgical complications (P = 0.001) compared with the rest of the cohort. Severe frailty was associated with a high risk of 30-day mortality (33% for patients with a clinical frailty scale score of 7-9 versus 3.6% for patients with a clinical frailty scale score of 1-3, P < 0.001). In a multivariate analysis, an increasing degree of clinical frailty was found to be significantly associated with developing at least one complication. CONCLUSION: Patients with frailty have a significantly increased risk of postoperative complications after major emergency abdominal surgery, especially atrial fibrillation, delirium, and pneumonia. Likewise, patients with frailty have an increased risk of mortality within 90 days. Thus, frailty is a significant predictor for adverse events after major emergency abdominal surgery and should be considered in all patients undergoing major emergency abdominal surgery.


Asunto(s)
Abdomen , Fragilidad , Complicaciones Posoperatorias , Humanos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Femenino , Masculino , Anciano , Fragilidad/complicaciones , Estudios Prospectivos , Dinamarca/epidemiología , Abdomen/cirugía , Persona de Mediana Edad , Anciano de 80 o más Años , Factores de Riesgo , Neumonía/epidemiología , Neumonía/etiología , Delirio/etiología , Delirio/epidemiología , Anciano Frágil , Urgencias Médicas , Evaluación Geriátrica
8.
J Neurooncol ; 166(3): 503-511, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38336917

RESUMEN

BACKGROUND: The risk of recurrence is overestimated by the Kaplan-Meier method when competing events, such as death without recurrence, are present. Such overestimation can be avoided by using the Aalen-Johansen method, which is a direct extension of Kaplan-Meier that accounts for competing events. Meningiomas commonly occur in older individuals and have slow-growing properties, thereby warranting competing risk analysis. The extent to which competing events are considered in meningioma literature is unknown, and the consequences of using incorrect methodologies in meningioma recurrence risk analysis have not been investigated. METHODS: We surveyed articles indexed on PubMed since 2020 to assess the usage of competing risk analysis in recent meningioma literature. To compare recurrence risk estimates obtained through Kaplan-Meier and Aalen-Johansen methods, we applied our international database comprising ~ 8,000 patients with a primary meningioma collected from 42 institutions. RESULTS: Of 513 articles, 169 were eligible for full-text screening. There were 6,537 eligible cases from our PERNS database. The discrepancy between the results obtained by Kaplan-Meier and Aalen-Johansen was negligible among low-grade lesions and younger individuals. The discrepancy increased substantially in the patient groups associated with higher rates of competing events (older patients with high-grade lesions). CONCLUSION: The importance of considering competing events in recurrence risk analysis is poorly recognized as only 6% of the studies we surveyed employed Aalen-Johansen analyses. Consequently, most of the previous literature has overestimated the risk of recurrence. The overestimation was negligible for studies involving low-grade lesions in younger individuals; however, overestimation might have been substantial for studies on high-grade lesions.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Humanos , Anciano , Meningioma/patología , Neoplasias Meníngeas/patología , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/patología , Estudios Retrospectivos , Medición de Riesgo
9.
Cancer Cell Int ; 24(1): 75, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38355625

RESUMEN

PURPOSE: To examine the role of RhoB expression in relation to chemotherapy response, clinical outcomes and associated signaling pathways in colorectal cancer patients. MATERIALS AND METHODS: The study included 5 colon cancer cell lines, zebrafish embryos and 260 colorectal cancer patients treated with 5-fluorouracil (5-FU) and oxaliplatin (OXL). The methods consisted of CRISPR/Cas9, reactive oxygen species (ROS), caspase-3 activity, autophagy flux, in-silico RNA sequencing and immunohistochemistry. Gene expression analysis and pathway analysis were conducted using RNA-seq data. RESULTS: All cancer lines tested, including SW480, SW480-KO13 (RhoB knockout), SW480-KO55 (RhoB knockout), HCT116 and HCT116-OE (RhoB overexpressed), exhibited cytotoxicity to 5-FU and OXL. RhoB knockout cell lines demonstrated significantly reduced migration compared to the control cell lines. Furthermore, RhoB played a role in caspase-3-dependent apoptosis, regulation of ROS production and autophagic flux. The mRNA sequencing data indicated lower expression levels of oncogenes in RhoB knockout cell lines. The zebrafish model bearing SW480-KO showed a light trend toward tumor regression. RhoB expression by immunohistochemistry in patients was increased from normal mucosa to tumor samples. In patients who received chemotherapy, high RhoB expression was related to worse survival compared to low RhoB expression. Furthermore, the molecular docking analysis revealed that OXL had a higher binding affinity for RhoB than 5-FU, with a binding affinity of -7.8 kcal/mol and HADDOCK predicted molecular interactions between RhoB and caspase 3 protein. Gene-set enrichment analysis supported these findings, showing that enrichment of DNA damage response pathway and p53 signaling in RhoB overexpression treatment group, while the RhoB knockout treatment group exhibited enrichment in the negative regulation pathway of cell migration. CONCLUSION: RhoB was negatively associated with chemotherapy response and survival in colorectal cancers. Therefore, RhoB inhibition may enhance chemotherapeutic responses and patient survival.

10.
NPJ Precis Oncol ; 8(1): 53, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38413842

RESUMEN

Epithelial ovarian cancer (EOC) is the gynaecological malignancy with highest mortality. Although adjuvant treatment with carboplatin and paclitaxel leads to an objective response in ~80% of these patients, a majority will relapse within two years. Better methods for assessing long-term treatment outcomes are needed. To address this, we established safe and efficacious doses of carboplatin and paclitaxel using IGROV-1 zebrafish-CDX models. Then fluorescently-labelled cell suspensions from 83 tumour biopsies collected at exploratory laparotomy of women with suspected EOC were generated and 37 (45%) were successfully implanted in zebrafish larvae. Among these 19 of 27 pathology-confirmed EOC samples (70%) engrafted. These zebrafish patient-derived tumour xenograft (ZTX) models were treated with carboplatin or paclitaxel and tumour growth/regression and metastatic dissemination were recorded. In a subgroup of nine patients, four ZTX models regressed during carboplatin treatment. All four corresponding patients had >24 months PFS. Furthermore, both ZTX models established from two patients having <24 months PFS failed to regress during carboplatin treatment. Seven of eight models seeding <6 metastatic cells were established from patients having >24 months PFS. In eleven of fourteen patients, FIGO stage I + II or III tumours gave rise to ZTX models seeding <4 or >4 metastatic cells, respectively. In conclusion, ZTX models predicted patients having >24 or <24 months PFS, based on response/no response to carboplatin. Furthermore, high metastatic dissemination in ZTX models correlated to shorter PFS and more advanced disease at diagnosis. These preliminary results suggest that ZTX models could become a useful prognostic tool in EOC treatment planning.

11.
Surg Endosc ; 38(4): 2010-2018, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38413471

RESUMEN

BACKGROUND: To investigate factors associated with risk for rebleeding and 30-day mortality following prophylactic transarterial embolization in patients with high-risk peptic ulcer bleeding. METHODS: We retrospectively reviewed medical records and included all patients who had undergone prophylactic embolization of the gastroduodenal artery at Rigshospitalet, Denmark, following an endoscopy-verified and treated peptic Sulcer bleeding, from 2016 to 2021. Data were collected from electronic health records and imaging from the embolization procedures. Primary outcomes were rebleeding and 30-day mortality. We performed logistical regression analyses for both outcomes with possible risk factors. Risk factors included: active bleeding; visible hemoclips; Rockall-score; anatomical variants; standardized embolization procedure; and number of endoscopies prior to embolization. RESULTS: We included 176 patients. Rebleeding occurred in 25% following embolization and 30-day mortality was 15%. Not undergoing a standardized embolization procedure increased the odds of both rebleeding (odds ratio 3.029, 95% confidence interval (CI) 1.395-6.579) and 30-day overall mortality by 3.262 (1.252-8.497). More than one endoscopy was associated with increased odds of rebleeding (odds ratio 2.369, 95% CI 1.088-5.158). High Rockall-score increased the odds of 30-day mortality (odds ratio 2.587, 95% CI 1.243-5.386). Active bleeding, visible hemoclips, and anatomical variants did not affect risk of rebleeding or 30-day mortality. Reasons for deviation from standard embolization procedure were anatomical variations, targeted treatment without embolizing the gastroduodenal artery, and technical failure. CONCLUSIONS: Deviation from the standard embolization procedure increased the risk of rebleeding and 30-day mortality, more than one endoscopy prior to embolization was associated with higher odds of rebleeding, and a high Rockall-score increased the risk of 30-day mortality. We suggest that patients with these risk factors are monitored closely following embolization. Early detection of rebleeding may allow for proper and early re-intervention.


Asunto(s)
Hemostasis Endoscópica , Úlcera Péptica , Humanos , Estudios Retrospectivos , Hemostasis Endoscópica/métodos , Factores de Riesgo , Úlcera Péptica Hemorrágica/etiología , Úlcera Péptica Hemorrágica/terapia , Úlcera Péptica/terapia , Recurrencia
12.
Eur J Orthop Surg Traumatol ; 34(3): 1479-1486, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38253932

RESUMEN

PURPOSE: The Focused Assessment with Sonography for Trauma (FAST) is a tool to rapidly detect intraabdominal and intrapericardial fluid with point-of-care ultrasound. Previous studies have questioned the role of FAST in patients with pelvic fractures. The aim of the present study was to assess the accuracy of FAST to detect clinically significant intraabdominal hemorrhage in patients with pelvic fractures. METHODS: We included all consecutive patients with pelvic and/or acetabular fractures treated our Level 1 trauma center from 2009-2020. We registered patient and fracture characteristics, FAST investigations and CT descriptions, explorative laparotomy findings, and transfusion needs. We compared FAST to CT and laparotomy findings, and calculated true positive and negative findings, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). RESULTS: We included 389 patients. FAST had a sensitivity of 75%, a specificity of 98%, a PPV of 84%, and a NPV of 96% for clinically significant intraabdominal bleeding. Patients with retroperitoneal hematomas were at increased risk for laparotomy both because of True-negative FAST and False-positive FAST. CONCLUSION: FAST is accurate to identify clinically significant intraabdominal blood in patients with severe pelvic fractures and should be a standard asset in these patients. Retroperitoneal hematomas challenge the FAST interpretation and thus the decision making when applying FAST in patients with pelvic fractures.


Asunto(s)
Fracturas Óseas , Fracturas de Cadera , Huesos Pélvicos , Fracturas de la Columna Vertebral , Heridas no Penetrantes , Humanos , Fracturas Óseas/complicaciones , Fracturas Óseas/diagnóstico por imagen , Hematoma/complicaciones , Hemoperitoneo/etiología , Fracturas de Cadera/complicaciones , Huesos Pélvicos/diagnóstico por imagen , Huesos Pélvicos/lesiones , Estudios Retrospectivos , Sensibilidad y Especificidad , Fracturas de la Columna Vertebral/complicaciones , Heridas no Penetrantes/complicaciones
13.
J Chem Phys ; 160(2)2024 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-38214392

RESUMEN

For large plasmonic nanoparticles, retardation effects become important once their length becomes comparable to the wavelength of light. However, most models do not incorporate retardation effects due to the high computational cost of solving for the optical properties of large atomistic electrodynamics systems. In this work, we derive and implement a recursive fast multipole method (FMM) in Cartesian coordinates that includes retardation effects. In this method, higher-order electrodynamic interaction tensors used for the FMM are calculated recursively, thus greatly reducing the implementation complexity of the model. This method allows for solving of the optical properties of large atomistic nanoparticles with controlled accuracy; in practice, taking the expansion to the fifth order provides a good balance of accuracy and computational time. Finally, we study the effects retardation has on the near- and far-field properties of large plasmonic nanoparticles with over a million atoms using this method. We specifically focus on nanorods and their dimers, which are known to generate highly confined fields in their junctions. In the future, this method can be applied to simulations in which accurate near-field properties are required, such as surface-enhanced Raman scattering.

14.
J Chem Phys ; 160(1)2024 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-38174789

RESUMEN

Strong light-matter interactions significantly modify the optical properties of molecules in the vicinity of plasmonic metal nanoparticles. Since the dimension of the plasmonic cavity approaches that of the molecules, it is critical to explicitly describe the nanoparticle junctions. In this work, we use the discrete interaction model/quantum mechanical (DIM/QM) method to model the coupling between the plasmonic near-field and molecular excited states. DIM/QM is a combined electrodynamics/quantum mechanical model that uses an atomistic description of the nanoparticle. We extend the DIM/QM method to include the local field effects in the sum-over-state formalism of time-dependent density functional theory. As a test of the method, we study the interactions between small organic chromophores and metal nanoparticles. In particular, we examine how the inclusion of multiple electronic transitions and intermolecular interactions modify the coupling between molecules and nanoparticles. Using the sum-over-state formalism of DIM/QM, we show that two-state models break down when the plasmon excitation is detuned from the molecular excitations. To gain further insight, we compare the simple coupled-dipole model (CDM) with the DIM/QM model. We find that CDM works well for simple systems but fails when going beyond the single molecule or single nanoparticle cases. We also find that the coupling depends strongly on the site of the nanoparticle in which the chromophore couples to. Our work suggests the importance of explicitly describing the cavity to capture the atomistic level local field environment in which the molecule strongly couples to.

15.
J Chem Theory Comput ; 20(2): 937-945, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38164716

RESUMEN

DNA-stabilized silver nanoclusters have emerged as an intriguing type of nanomaterial due to their unique optical and electronic properties, with potential applications in areas such as biosensing and imaging. The development of efficient methods for modeling these properties is paramount for furthering the understanding and utilization of these clusters. In this study, a hybrid quantum mechanical and molecular mechanical approach for modeling the optical properties of a DNA-templated silver nanocluster is evaluated. The influence of different parameters, including ligand fragmentation, damping, embedding potential, basis set, and density functional, is investigated. The results demonstrate that the most important parameter is the type of atomic properties used to represent the ligands, with isotropic dipole-dipole polarizabilities outperforming the rest. This underscores the importance of an appropriate representation of the ligands, particularly through the selection of the properties used to represent them. Moreover, the results are compared to experimental data, showing that the applied methodology is reliable and effective for the modeling of DNA-stabilized silver nanoclusters. These findings offer valuable insights that may guide future computational efforts to explore and harness the potential of these novel systems.


Asunto(s)
ADN , Plata , Simulación de Dinámica Molecular
16.
Biochim Biophys Acta Mol Basis Dis ; 1870(2): 166963, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37989423

RESUMEN

Choroideremia (CHM) is a rare X-linked chorioretinal dystrophy affecting the photoreceptors, retinal pigment epithelium (RPE) and choroid, however, the involvement of the choroid in disease progression is not fully understood. CHM is caused by mutations in the CHM gene, encoding the ubiquitously expressed Rab escort protein 1 (REP1). REP1 plays an important role in intracellular trafficking of vesicles, including melanosomes. In this study, we examined the ultrastructure of the choroid in chmru848 fish and Chmnull/WT mouse models using transmission electron and confocal microscopy. Significant pigmentary disruptions were observed, with lack of melanosomes in the choroid of chmru848 fish from 4 days post fertilisation (4dpf), and a reduction in choroidal blood vessel diameter and interstitial pillars suggesting a defect in vasculogenesis. Total melanin and expression of melanogenesis genes tyr, tryp1a, mitf, dct and pmel were also reduced from 4dpf. In Chmnull/WT mice, choroidal melanosomes were significantly smaller at 1 month, with reduced eumelanin at 1 year. The choroid in CHM patients were also examined using spectral domain optical coherence tomography (SD-OCT) and OCT-angiography (OCT-A) and the area of preserved choriocapillaris (CC) was found to be smaller than that of overlying photoreceptors, suggesting that the choroid is degenerating at a faster rate. Histopathology of an enucleated eye from a 74-year-old CHM male patient revealed isolated areas of RPE but no associated underlying CC. Pigmentary disruptions in CHM animal models reveal an important role for REP1 in melanogenesis, and drugs that improve melanin production represent a potential novel therapeutic avenue.


Asunto(s)
Coroideremia , Anciano , Animales , Humanos , Masculino , Ratones , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Coroides/metabolismo , Coroideremia/genética , Coroideremia/patología , Coroideremia/terapia , Melaninas , Melanogénesis , Ratones Noqueados
18.
Open Res Eur ; 3: 88, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37981907

RESUMEN

Background: Uveal melanoma is a poor prognosis cancer. Ergolide, a sesquiterpene lactone isolated from Inula Brittanica, exerts anti-cancer properties. The objective of this study was to 1) evaluate whether ergolide reduced metastatic uveal melanoma (MUM) cell survival/viability in vitro and in vivo; and 2) to understand the molecular mechanism of ergolide action. Methods: Ergolide bioactivity was screened via long-term proliferation assay in UM/MUM cells and in zebrafish MUM xenograft models. Mass spectrometry profiled proteins modulated by ergolide within whole cell or extracellular vesicle (EVs) lysates of the OMM2.5 MUM cell line. Protein expression was analyzed by immunoblots and correlation analyses to UM patient survival used The Cancer Genome Atlas (TCGA) data. Results: Ergolide treatment resulted in significant, dose-dependent reductions (48.5 to 99.9%; p<0.0001) in OMM2.5 cell survival in vitro and of normalized primary zebrafish xenograft fluorescence (56%; p<0.0001) in vivo, compared to vehicle controls. Proteome-profiling of ergolide-treated OMM2.5 cells, identified 5023 proteins, with 52 and 55 proteins significantly altered at 4 and 24 hours, respectively ( p<0.05; fold-change >1.2). Immunoblotting of heme oxygenase 1 (HMOX1) and growth/differentiation factor 15 (GDF15) corroborated the proteomic data. Additional proteomics of EVs isolated from OMM2.5 cells treated with ergolide, detected 2931 proteins. There was a large overlap with EV proteins annotated within the Vesiclepedia compendium. Within the differentially expressed proteins, the proteasomal pathway was primarily altered. Interestingly, BRCA2 and CDKN1A Interacting Protein (BCCIP) and Chitinase Domain Containing 1 (CHID1), were the only proteins significantly differentially expressed by ergolide in both the OMM2.5 cellular and EV isolates and they displayed inverse differential expression in the cells versus the EVs. Conclusions: Ergolide is a novel, promising anti-proliferative agent for UM/MUM. Proteomic profiling of OMM2.5 cellular/EV lysates identified candidate pathways elucidating the action of ergolide and putative biomarkers of UM, that require further examination.


The most common form of adult eye cancer is uveal melanoma (UM). Once UM cancer cells spread to organs in the rest of the body, metastatic UM (MUM), there is a poor prognosis for patients with only one approved drug treatment. Hence, it is vital to better understand the cellular and extracellular proteins that regulate UM pathology in order to uncover biomarkers of disease and therapeutic targets. In this original study, we demonstrate a compound called ergolide is capable of severely reducing the metabolic activity and growth of UM cancer cells, grown as isolated monolayers. Ergolide was also able to reduce the growth of human MUM cells growing as tumors in transplanted zebrafish larvae. We identify that ergolide alters specific proteins found in the human UM cells. These proteins once analyzed in detail offer opportunities to understand how new treatment strategies can be developed for UM.

19.
Chem Commun (Camb) ; 59(98): 14524-14527, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-37966800

RESUMEN

Gold nanoparticles were functionalized with natural abundance and 13C-labeled N-heterocyclic carbenes (NHCs) to investigate the Au-C stretch. A combinatorial approach of surface enhanced Raman spectroscopy (SERS) and density-functional theory (DFT) calculations highlighted vibrational modes significantly impacted by isotopic labeling at the carbene carbon. Critically, no isotopically-impacted stretching mode showed majority Au-C character.

20.
Adv Drug Deliv Rev ; 201: 115084, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37689278

RESUMEN

Ocular surface neovascularization and its resulting pathological changes significantly alter corneal refraction and obstruct the light path to the retina, and hence is a major cause of vision loss. Various factors such as infection, irritation, trauma, dry eye, and ocular surface surgery trigger neovascularization via angiogenesis and lymphangiogenesis dependent on VEGF-related and alternative mechanisms. Recent advances in antiangiogenic drugs, nanotechnology, gene therapy, surgical equipment and techniques, animal models, and drug delivery strategies have provided a range of novel therapeutic options for the treatment of ocular surface neovascularization. In this review article, we comprehensively discuss the etiology and mechanisms of corneal neovascularization and other types of ocular surface neovascularization, as well as emerging animal models and drug delivery strategies that facilitate its management.


Asunto(s)
Neovascularización de la Córnea , Medicina Molecular , Animales , Neovascularización Patológica/tratamiento farmacológico , Neovascularización de la Córnea/tratamiento farmacológico , Neovascularización de la Córnea/patología , Retina/patología , Inhibidores de la Angiogénesis/uso terapéutico
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