Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.683
Filtrar
1.
Mol Cancer Ther ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39331510

RESUMEN

The enhanced permeability and retention (EPR) effect controls passive nanodrug uptake in tumors, and may provide a high tumor payload with prolonged retention for cancer treatment. However, EPR-mediated tumor uptake and distribution vary by cancer phenotype. Thus, we hypothesized that a companion PET-imaging surrogate may benefit EPR-mediated therapeutic drug delivery. We developed two 89Zr-radiolabeled nanocarriers based on 4-armed-starPEG40kDa with or without talazoparib (TLZ), a potent PARPi, as surrogates for the PEG-TLZ4 therapeutic scaffold. For PET imaging, PEG-DFB4 and PEG-DFB1-TLZ3 were radiolabeled with 89Zr by replacing one or all four TLZ on PEG-TLZ4 with deferoxamine B (DFB). The radiolabeled nanodrugs [89Zr]PEG-DFB4 and [89Zr]PEG-DFB1-TLZ3 were tested in vivo in prostate cancer subcutaneous xenografts (22Rv1, LTL-545, and LTL-610) and 22Rv1 metastatic models. Their EPR-mediated tumoral uptake and penetration was compared to CT26, a known EPR-high MicroPET/CT images, organ biodistribution, and calculated kinetic parameters showed high uptake in CT26 and LTL-545, moderate to low uptake in LTL-610 and 22Rv1. MicroPET/CT and high-resolution autoradiographic images showed nanocarrier penetration into highly permeable CT26, but heterogeneous peripheral accumulation was observed in LTL-545, LTL-610, and 22Rv1 subcutaneous xenografts and metastatic tumors. CD31 staining of tumor sections showed homogenous vascular development in CT26 tumors and heterogeneity in other xenografts. Both [89Zr]PEG-DFB4 and [89Zr]PEG-DFB1-TLZ3 showed similar accumulation and distribution in subcutaneous and metastatic tumor models. Both nanocarriers can measure tumor model passive uptake heterogeneity. Although heterogeneous, prostate cancer xenografts had low EPR. These starPEG nanocarriers could be used as PET imaging surrogates to predict drug delivery and efficacy.

2.
Med Image Anal ; 98: 103300, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39226710

RESUMEN

Image-to-image translation is a vital component in medical imaging processing, with many uses in a wide range of imaging modalities and clinical scenarios. Previous methods include Generative Adversarial Networks (GANs) and Diffusion Models (DMs), which offer realism but suffer from instability and lack uncertainty estimation. Even though both GAN and DM methods have individually exhibited their capability in medical image translation tasks, the potential of combining a GAN and DM to further improve translation performance and to enable uncertainty estimation remains largely unexplored. In this work, we address these challenges by proposing a Cascade Multi-path Shortcut Diffusion Model (CMDM) for high-quality medical image translation and uncertainty estimation. To reduce the required number of iterations and ensure robust performance, our method first obtains a conditional GAN-generated prior image that will be used for the efficient reverse translation with a DM in the subsequent step. Additionally, a multi-path shortcut diffusion strategy is employed to refine translation results and estimate uncertainty. A cascaded pipeline further enhances translation quality, incorporating residual averaging between cascades. We collected three different medical image datasets with two sub-tasks for each dataset to test the generalizability of our approach. Our experimental results found that CMDM can produce high-quality translations comparable to state-of-the-art methods while providing reasonable uncertainty estimations that correlate well with the translation error.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos
3.
Inflamm Bowel Dis ; 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39321100

RESUMEN

BACKGROUND: Given the paucity of long-term longitudinal data for inflammatory bowel disease type unclassified (IBDU), we aimed to clarify IBDU disease course and reclassification rate by presenting nationwide data with up to 20 years of follow-up. METHODS: We analyzed a prospectively identified 11-year cohort of pediatric patients diagnosed with IBDU between January 1, 2003 and December 31, 2013 at all Scottish pediatric IBD centers and followed up into adult services until December 31, 2022. Data were obtained from electronic medical records at fixed timepoints (5 and 10 years post-diagnosis) and at the final follow-up. RESULTS: Overall, 102 patients were included in the analysis (57/102 [56%] male, median [interquartile range {IQR}] age at diagnosis: 11.5 [9.1-13.2] years) with a median (IQR) follow-up length of 10.5 (8.6-14.0) years. A change of diagnosis was made in 61 of 102 patients (60%); of these, 30 patients (29%) were reclassified to Crohn's disease (CD) and 31 patients (30%) to ulcerative colitis (UC). Patients who remained with IBDU had higher 1- to 5-year remission rates (IBDU 30/39 [77%] vs reclassified 16/57 [28%], P < .05), with lower rates of moderate-to-severe disease (IBDU 3/39 [8%] vs reclassified 31/57 [54%], P < .05) and less need for biologics across all timepoints (IBDU vs reclassified: first timepoint 1/39 [3%] vs 17/57 [30%], second timepoint 1/33 [3%] vs 26/56 [46%], third timepoint 0/18 [0%] vs 16/33 [49%]; all P < .05). Higher rates of surgical resections were observed in reclassified patients (reclassified 11/61 [18%] vs IBDU 1/41 [2%], P = .02). CONCLUSIONS: In our nationwide pediatric IBDU cohort, 60% of patients were reclassified to either UC or CD over 10.5 years of median follow-up; those who remained with IBDU had a milder disease course.


We present a nationwide cohort of pediatric patients with inflammatory bowel disease unclassified with up to 20 years of follow-up, showing that 60% of patients were reclassified to either Crohn's disease or ulcerative colitis. Those whose diagnosis remained unchanged had a milder disease course.

4.
Artículo en Inglés | MEDLINE | ID: mdl-39280963

RESUMEN

Background: Tension-free end-to-end digital nerve repair or reconstruction under loupe or microscope magnification are surgical treatment options for lacerated digital nerves in patients with multiple injured digits, injuries to the border digits, or injuries to the thumb, with the goal of improved or restored sensation and a decreased risk of painful traumatic neuroma formation. Different techniques for primary repair have been described and include epineurial sutures, nerve "glues" including fibrin-based gels1,2, biologic or synthetic absorbable or nonabsorbable nerve wraps or conduits, or a combination of these materials. Nerve "glues" have demonstrated decreased initial gapping at the repair site3 and an increased tensile load to failure when utilized with a nerve wrap or conduit4,5. When there is a gap or defect in the nerve and primary repair is not feasible, nerve allograft and autograft provide similar results and are both better options than conduit reconstruction6. Concomitant or isolated digital vascular injuries may also be surgically treated with end-to-end repair in a dysvascular digit, with the goal of digit and function preservation. In the absence of complete circumferential injury or complete amputation, redundant or collateral flow may be present. Single digital artery injuries often do not need to be repaired because of the collateral flow from the other digital artery. Description: Digital nerve and vascular injuries are often found in the context of traumatic wounds. In such cases, surgical exploration is often required, with possible surgical extension of the wounds to facilitate identification of the neurovascular bundles. The proximal and distal ends of the transected nerve and/or artery are identified, and the traumatized ends are incised sharply, maintaining as much length as possible to facilitate end-to-end repair, interposition of a graft, and the use of a conduit. The proximal and distal aspects of the nerve and/or artery are appropriately mobilized by dissecting or releasing any scar tissue or soft tissue that may be tethering the structure. The defect is measured in the natural resting position of the digit. Gentle flexion of the digit may be performed to facilitate a primary repair in the setting of very small defects. Primary repair or reconstruction is selected, and an 8-0 or 9-0 nonabsorbable monofilament suture is utilized to anastomose the appropriate structures under magnification with use of a single or double stitch6. A tubular nerve conduit is placed prior to epineurial suturing, or a nerve conduit wrap is applied circumferentially around the repair site and augmented with a fibrin glue. The wound is then irrigated and closed in a standard fashion, as determined by the presence of any soft-tissue or structural injury. Alternatives: Alternatives to primary repair include the use of conduits or autologous or allogenic grafting. Factors that necessitate reconstruction include gapping and poor soft-tissue integrity, which can be related to the mechanism of injury. Alternatives to repair or reconstruction include treatment of the-soft tissue or structural injury without concomitant repair or reconstruction of the damaged digital nerves or vessels. Rationale: Primary end-to-end repair and reconstruction of digital nerves increases a patient's likelihood of sensation recovery, and arterial repair can preserve a digit and avoid the need for amputation. Sensation in the digits is very important for fine motor skills and interaction with the environment, and it is particularly important for patients who rely on their hands for work and/or recreation. For these reasons, the digital nerves to the border digits, such as the ulnar aspect of the small finger, radial aspect of the index finger, and both digital nerves to the thumb, are given particular attention. Expected Outcomes: Surgical intervention to repair or reconstruct the digital nerves increases the likelihood of recovering pre-injury sensation; however, the chance of complete recovery remains low. A systematic review of the outcomes of digital nerve repair in adults published in 2019 showed that the average percentage of patients who had undergone repair and reported a recovery to Highet grade 4 was 24% (range, 6% to 60%)8. The rate of adverse events was comparable between the operatively and nonoperatively treated patients, with complications including neuromas, hyperesthesia, and infection. Important Tips: The use of a microvascular background material can provide better visualization of the proximal and distal ends while performing the repair.It is important to sharply guillotine the ends of the nerve to freshen up the laceration and provide healthy nerve ends for repair.Repair sutures need to be passed through the epineurium, with care taken not to pass through the nerve fascicles. Acronyms and Abbreviations: OR = operating roomPIP = proximal interphalangealPT = prothrombin timePTT = partial thromboplastin time.

5.
bioRxiv ; 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39282455

RESUMEN

The SNM1A exonuclease plays a key role in repair of interstrand crosslinks (ICLs) which represent a particularly toxic class of DNA damage. Previous work suggests that the SWI/SNF family ATP-dependent, chromatin remodeler, Cockayne Syndrome B protein (CSB) interacts with SNM1A, during transcription-coupled DNA interstrand crosslink repair (TC-ICL repair). Here, we validate this interaction using purified proteins and demonstrate that the ubiquitin-binding and winged-helix domains of CSB are required for interaction with the catalytic domain of SNM1A. The winged helix domain is essential for binding, although high-affinity SNM1A binding requires the entire CSB C-terminal region (residues 1187-1493), where two copies of the C-terminal domain of CSB are necessary for a stable interaction with SNM1A. CSB stimulates SNM1A nuclease activity on varied model DNA repair intermediate substrates. Importantly, CSB was observed to stimulate digestion through ICLs in vitro , implying a key role of the interaction in 'unhooking' during TC-ICL repair. AlphaFold3 models of CSB constructs complexed with the SNM1A catalytic domain enabled mapping of the molecular contacts required for the CSB-SNM1A interaction. This identified specific protein-protein interactions necessary for CSB's stimulation of SNM1A's activity that we confirmed experimentally. Additionally, our studies reveal the C-terminal region of CSB as a novel DNA binding region that also is involved in stimulation of SNM1A-mediated ICL repair. Moreover, targeting protein-protein interactions that are vital for specific nuclease activities, such as CSB's stimulation of SNM1A's nuclease activity, may be a productive alternative therapeutic strategy to nuclease active site inhibition.

6.
Clin Infect Dis ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39282957

RESUMEN

BACKGROUND: Prisons provide a key strategic opportunity to upscale hepatitis C testing and treatment in a high prevalence setting and are crucial for elimination efforts. METHODS: A decentralized, statewide nurse-led model of care offering hepatitis C treatment for people in prison was implemented in Victoria, Australia in 2015. The program provides hepatitis C care to all 14 adult prison sites in the jurisdiction. We prospectively evaluated treatment uptake between 1 November 2015 and 31 December 2021. Data on all people in prison treated were recorded in a clinical database. The primary outcomes were i) total number of people in prison with hepatitis C treated; ii) total number of DAA treatment courses. RESULTS: 3,133 DAA treatment courses were prescribed to 2,768 people in prison. The proportion of total Victoria DAA prescriptions the program was responsible for increased from 6% in 2016 to a peak of 23% in 2020. Of those treated, median age was 39 years, 91% were male and 9% had cirrhosis. Few (20%) had previously engaged in hepatitis C care in the community and at first treatment course in prison, only 6% had previously accessed hepatitis C treatment. Complete follow up data were available for 1,757/2,768 (63%) treated, with 1,627/1,757 (93%) achieving SVR12. CONCLUSIONS: A decentralized, nurse-led, statewide model of care was highly effective in treating large numbers of people in prison with hepatitis C and achieved high rates of SVR12. Nurse-led prison programs are playing a crucial role in eliminating hepatitis C as a public health threat in Australia.

7.
Mol Cancer Ther ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235218

RESUMEN

Targeting synthetic lethal interactions between genes has emerged as a promising strategy for cancer therapy. This study explores the intricate interplay between terminal uridyltransferase 4 (TUT4) and terminal uridyltransferase 7 (TUT7), the 3'-5' exoribonuclease DIS3L2, and the SKI complex-interacting factor Focadhesin (FOCAD) in the context of cancer vulnerability. Using CRISPR and public functional genomics data, we show impairment of cell proliferation upon knockout of TUT7 or DIS3L2, but not TUT4, on cancer cells with FOCAD loss. Moreover, we report the characterization of the first potent and selective TUT4/7 inhibitors that substantially reduce uridylation and demonstrate in vitro and in vivo antiproliferative activity specifically in FOCAD-deleted cancer. FOCAD deficiency post-transcriptionally disrupts the stability of the SKI complex, whose role is to safeguard cells against aberrant RNA. Re-introduction of FOCAD restores the SKI complex and makes these cells less sensitive to TUT4/7 inhibitors, indicating that TUT7 dependency is FOCAD loss-driven. We propose a model where, in absence of FOCAD, TUT7 and DIS3L2 function as a salvage mechanism that degrades aberrant RNA, and genetic or pharmacological inhibition of this pathway leads to cell death. Our findings underscore the significance of FOCAD loss as a genetic driver of TUT7 vulnerability and provide insights into the potential utility of TUT4/7 inhibitors for cancer treatment.

8.
Transl Lung Cancer Res ; 13(8): 1907-1917, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39263016

RESUMEN

Background: Radiomics has shown promise in improving malignancy risk stratification of indeterminate pulmonary nodules (IPNs) with many platforms available, but with no head-to-head comparisons. This study aimed to evaluate transportability of radiomic models across platforms by comparing performances of a commercial radiomic feature extractor (HealthMyne) with an open-source extractor (PyRadiomics) on diagnosis of lung cancer in IPNs. Methods: A commercial radiomic feature extractor was used to segment IPNs from computed tomography (CT) scans, and a previously validated radiomic model based on commercial features was used as baseline (ComRad). Using same segmentation masks, PyRadiomics, an open-source feature extractor was used to build three open-source radiomic models (OpenRad) using different methods: de novo open-source model derived using least absolute shrinkage and selection operator (LASSO) for feature selection, selecting open-source features matched to ComRad features based upon Imaging Biomarker Standardization Initiative (IBSI) nomenclature, and selecting open-source features most highly correlated to ComRad features. Radiomic models were trained on an internal cohort (n=161) and externally validated on 3 cohorts (n=278). We added Mayo clinical risk score to OpenRad and ComRad models, creating integrated clinical radiomic (ClinRad) models. All models were compared using area under the curve (AUC) and evaluated for clinical improvement using bias-corrected clinical net reclassification indices (cNRIs). Results: ComRad AUC was 0.76 [95% confidence interval (CI): 0.71-0.82], and OpenRad AUC was 0.75 (95% CI: 0.69-0.81) for LASSO model, 0.74 (95% CI: 0.68-0.79) for Spearman's correlation, and 0.71 (95% CI: 0.65-0.77) for IBSI. Mayo scores were added to OpenRad LASSO model, which performed best, forming open-source ClinRad model with AUC of 0.80 (95% CI: 0.74-0.86), identical to commercial ClinRad's AUC. Both ClinRad models showed clinical improvement compared to Mayo alone, with commercial ClinRad achieving cNRI of 0.09 (95% CI: 0.02-0.15) for benign and 0.07 (95% CI: 0.00-0.13) for malignant, and open-source ClinRad achieving cNRI of 0.09 (95% CI: 0.02-0.15) for benign and 0.06 (95% CI: 0.00-0.12) for malignant. Conclusions: Transportability of radiomic models across platforms directly does not conserve performance, but radiomic platforms can provide equivalent results when building de novo models allowing for flexibility in feature selection to maximize prediction accuracy.

9.
R Soc Open Sci ; 11(8): 240616, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39113770

RESUMEN

Omega-3 long-chain polyunsaturated fatty acids (n3-LCPUFAs) are produced primarily in aquatic ecosystems and are considered essential nutrients for predators given their structural role in vertebrates' cerebral tissues. Alarmingly, with urbanization, many aquatic animals now rely on anthropogenic foods lacking n3-LCPUFAs. In this study undertaken in Newfoundland (Canada), we tested whether recent or longer term diet explains the cerebral fatty acid composition of ring-billed gulls (Larus delawarensis), a seabird that now thrives in cities. During the breeding season, cerebral levels of n3-LCPUFAs were significantly higher for gulls nesting in a natural habitat and foraging on marine food (mean ± s.d.: 32 ± 1% of total identified fatty acids) than for urban nesters exploiting rubbish (27 ± 1%). Stable isotope analysis of blood and feathers showed that urban and natural nesters shared similar diets in autumn and winter, suggesting that the difference in cerebral n3-LCPUFAs during the breeding season was owing to concomitant and transient differences in diet. We also experimentally manipulated gulls' diets throughout incubation by supplementing them with fish oil rich in n3-LCPUFAs, a caloric control lacking n3-LCPUFAs, or nothing, and found evidence that fish oil increased urban nesters' cerebral n3-LCPUFAs. These complementary analyses provide evidence that the brain of this seabird remains plastic during adulthood and responds to short-term dietary changes.

10.
Alzheimers Dement ; 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39096164

RESUMEN

INTRODUCTION: We developed a multimarker blood test result interpretation tool for the clinical dementia practice, including phosphorylated (P-)tau181, amyloid-beta (Abeta)42/40, glial fibrillary acidic protein (GFAP), and neurofilament light (NfL). METHODS: We measured the plasma biomarkers with Simoa (n = 1199), applied LASSO regression for biomarker selection and receiver operating characteristics (ROC) analyses to determine diagnostic accuracy. We validated our findings in two independent cohorts and constructed a visualization approach. RESULTS: P-tau181, GFAP, and NfL were selected. This combination had area under the curve (AUC) = 83% to identify amyloid positivity in pre-dementia stages, AUC = 87%-89% to differentiate Alzheimer's or controls from frontotemporal dementia, AUC = 74%-76% to differentiate Alzheimer's or controls from dementia with Lewy bodies. Highly reproducible AUCs were obtained in independent cohorts. The resulting visualization tool includes UpSet plots to visualize the stand-alone biomarker results and density plots to visualize the biomarker results combined. DISCUSSION: Our multimarker blood test interpretation tool is ready for testing in real-world clinical dementia settings. HIGHLIGHTS: We developed a multimarker blood test interpretation tool for clinical dementia practice. Our interpretation tool includes plasma biomarkers P-tau, GFAP, and NfL. Our tool is particularly useful for Alzheimer's and frontotemporal dementia diagnosis.

11.
Chem Sci ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39156927

RESUMEN

Designing molecules that can undergo late-stage modifications resulting in specific optical properties is useful for developing structure-function trends in materials, which ultimately advance optoelectronic applications. Herein, we report a series of fused diborepinium ions stabilized by carbene and carbone ligands (diamino-N-heterocyclic carbenes, cyclic(alkyl)(amino) carbenes, carbodicarbenes, and carbodiphosphoranes), including a detailed bonding analysis. These are the first structurally confirmed examples of diborepin dications and we detail how distortions in the core of the pentacyclic fused system impact aromaticity, stability, and their light-emitting properties. Using the same fused diborepin scaffold, coordinating ligands were used to dramatically shift the emission profile, which exhibit colors ranging from blue to red (358-643 nm). Notably, these diborepinium ions access expanded regions of the visible spectrum compared to known examples of borepins, with quantum yields up to 60%. Carbones were determined to be superior stabilizing ligands, resulting in improved stability in the solution and solid states. Density functional theory was used to provide insight into the bonding as well as the specific transitions that result in the observed photophysical properties.

13.
Small ; : e2404351, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39161205

RESUMEN

Titanium and titanium alloys remain the gold standard for dental and orthopedic implants. These materials are heavily used because of their bioinert nature, robust mechanical properties, and seamless integration with bone. However, implant-associated infections (IAIs) remain one of the leading causes of implant failure. Eradicating an IAI can be difficult since bacteria can form biofilms on the medical implant, protecting the bacterial cells against systemic antibiotics and the host's immune system. If the infection is not treated promptly and aggressively, device failure is inevitable, leading to costly multi-step revision surgeries. To circumvent this dire situation, scientists and engineers continue to develop novel strategies to protect the surface of medical implants from bacteria. In this review, details on emerging strategies to prevent infection in titanium implants are reported. These strategies include anti-adhesion properties provided by polymers, superhydrophobic, superhydrophilic, and liquid-infused surface coatings, as well as strategies and coatings employed to lyse the bacteria. Additionally, commercially available technologies and those under preclinical trials are examined while discussing current and future trends.

14.
J Orthop Trauma ; 38(9S): S21-S25, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39150290

RESUMEN

SUMMARY: Successful management of radial and ulnar shaft fractures is an essential skill for all orthopaedic surgeons. The frequent presentation of these injuries coupled with the nuanced anatomic considerations that must be observed for successful outcomes dictate that these injuries require a thorough understanding by the treating surgeon. Intraoperative care to restore the anatomic radial bow and rotation is essential for the resumption of functional forearm rotation postinjury. Often, problems arising during the operative treatment of radial and ulnar shaft fractures come in predictable patterns that can be mitigated with preoperative planning and sound technique. Cases of increased complexity with segmental bone defects and soft tissue defects require a variety of advanced reconstructive techniques.


Asunto(s)
Fracturas del Radio , Fracturas del Cúbito , Humanos , Fracturas del Cúbito/cirugía , Fracturas del Radio/cirugía , Fijación Interna de Fracturas/métodos , Procedimientos de Cirugía Plástica/métodos
15.
J Hand Surg Glob Online ; 6(4): 545-550, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39166195

RESUMEN

Purpose: The American Society for Surgery of the Hand developed the Surgery Training and Educational Platform (STEP) in order to assess essential skills in hand surgery. The American Society for Surgery of the Hand designed modules spanning both osseous and soft tissue skills aimed to be cost effective for the purpose of orthopedic surgical education. The STEP curriculum was adapted and implemented at a single military orthopedic residency program. Methods: The following six modules were implemented: (1) depth of plunge, (2) scaphoid pinning, (3) phalangeal fracture pinning, (4) microsurgery, (5) full-thickness skin graft harvest, and (6) wrist arthroscopy. Both first- (PGY1) and second-year (PGY2) residents participated. Scores were calculated according to the original STEP curriculum criteria and were compared with historic data from the previous year. All residents responded to an evaluation questionnaire following the performance of the tasks. Results: The PGY2 cohort outperformed PGY1 cohorts across all modules except for the depth of plunge and scaphoid fixation modules. In the phalangeal pinning module, PGY2s did significantly better when compared with pooled PGY1 performance and their own PGY1 performance (P < .05). In the microsurgery module, PGY2s scored better than pooled PGY1s. In the full-thickness skin grafting module, PGY2s outperformed PGY1s (P < .05). On the post-task evaluation, residents unanimously responded that this was a valuable exercise, but the time required to complete all the modules was significant, similar to that of the previous year survey. Conclusions: The STEP simulation is a cost effective and reliable program to engage residents in hand surgery-related skills. However, adaptations should be encouraged according to institutional resources to provide the most inclusive training platform possible per institutional constraints. The STEP simulation is interpreted by residents as a valuable exercise but requires a significant time commitment that could be a barrier to implementation and regular use. Type of study/level of evidence: Therapeutic IV.

16.
Bioengineering (Basel) ; 11(8)2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39199801

RESUMEN

This study aimed to investigate whether plaque characteristics derived from intravascular optical coherence tomography (IVOCT) could predict a long-term cardiovascular (CV) death. This study was a single-center, retrospective study on 104 patients who had undergone IVOCT-guided percutaneous coronary intervention. Plaque characterization was performed using Optical Coherence TOmography PlaqUe and Stent (OCTOPUS) software developed by our group. A total of 31 plaque features, including lesion length, lumen, calcium, fibrous cap (FC), and vulnerable plaque features (e.g., microchannel), were computed from the baseline IVOCT images. The discriminatory power for predicting CV death was determined using univariate/multivariate logistic regressions. Of 104 patients, CV death was identified in 24 patients (23.1%). Univariate logistic regression revealed that lesion length, calcium angle, calcium thickness, FC angle, FC area, and FC surface area were significantly associated with CV death (p < 0.05). In the multivariate logistic analysis, only the FC surface area (OR 2.38, CI 0.98-5.83, p < 0.05) was identified as a significant determinant for CV death, highlighting the importance of the 3D lesion analysis. The AUC of FC surface area for predicting CV death was 0.851 (95% CI 0.800-0.927, p < 0.05). Patients with CV death had distinct plaque characteristics (i.e., large FC surface area) in IVOCT. Studies such as this one might someday lead to recommendations for pharmaceutical and interventional approaches.

17.
Proc Natl Acad Sci U S A ; 121(35): e2400194121, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39172792

RESUMEN

Size-dependent phagocytosis is a well-characterized phenomenon in monocytes and macrophages. However, this size effect for preferential gene delivery to these important cell targets has not been fully exploited because commonly adopted stabilization methods for electrostatically complexed nucleic acid nanoparticles, such as PEGylation and charge repulsion, typically arrest the vehicle size below 200 nm. Here, we bridge the technical gap in scalable synthesis of larger submicron gene delivery vehicles by electrostatic self-assembly of charged nanoparticles, facilitated by a polymer structurally designed to modulate internanoparticle Coulombic and van der Waals forces. Specifically, our strategy permits controlled assembly of small poly(ß-amino ester)/messenger ribonucleic acid (mRNA) nanoparticles into particles with a size that is kinetically tunable between 200 and 1,000 nm with high colloidal stability in physiological media. We found that assembled particles with an average size of 400 nm safely and most efficiently transfect monocytes following intravenous administration and mediate their differentiation into macrophages in the periphery. When a CpG adjuvant is co-loaded into the particles with an antigen mRNA, the monocytes differentiate into inflammatory dendritic cells and prime adaptive anticancer immunity in the tumor-draining lymph node. This platform technology offers a unique ligand-independent, particle-size-mediated strategy for preferential mRNA delivery and enables therapeutic paradigms via monocyte programming.


Asunto(s)
Monocitos , Nanopartículas , ARN Mensajero , Monocitos/metabolismo , Nanopartículas/química , ARN Mensajero/genética , ARN Mensajero/metabolismo , Animales , Ratones , Humanos , Polielectrolitos/química , Macrófagos/metabolismo , Poliaminas/química , Tamaño de la Partícula , Diferenciación Celular , Técnicas de Transferencia de Gen , Células Dendríticas/metabolismo , Electricidad Estática , Polímeros
18.
Alzheimers Res Ther ; 16(1): 190, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39169442

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is a common, complex and multifactorial disease that may require screening across multiple routes of referral to enable early detection and subsequent future implementation of tailored interventions. Blood- and eye-based biomarkers show promise as low-cost, scalable and patient-friendly tools for early AD detection given their ability to provide information on AD pathophysiological changes and manifestations in the retina, respectively. Eye clinics provide an intriguing real-world proof-of-concept setting to evaluate the performance of these potential AD screening tools given the intricate connections between the eye and brain, presumed enrichment for AD pathology in the aging population with eye disorders, and the potential for an accelerated diagnostic pathway for under-recognized patient groups. METHODS: The BeyeOMARKER study is a prospective, observational, longitudinal cohort study aiming to include individuals visiting an eye-clinic. Inclusion criteria entail being ≥ 50 years old and having no prior dementia diagnosis. Excluded eye-conditions include traumatic insults, superficial inflammation, and conditions in surrounding structures of the eye that are not engaged in vision. The BeyeOMARKER cohort (n = 700) will undergo blood collection to assess plasma p-tau217 levels and a brief cognitive screening at the eye clinic. All participants will subsequently be invited for annual longitudinal follow-up including remotely administered cognitive screening and questionnaires. The BeyeOMARKER + cohort (n = 150), consisting of 100 plasma p-tau217 positive participants and 50 matched negative controls selected from the BeyeOMARKER cohort, will additionally undergo Aß-PET and tau-PET, MRI, retinal imaging including hyperspectral imaging (primary), widefield imaging, optical coherence tomography (OCT) and OCT-Angiography (secondary), and cognitive and cortical vision assessments. RESULTS: We aim to implement the current protocol between April 2024 until March 2027. Primary outcomes include the performance of plasma p-tau217 and hyperspectral retinal imaging to detect AD pathology (using Aß- and tau-PET visual read as reference standard) and to detect cognitive decline. Initial follow-up is ~ 2 years but may be extended with additional funding. CONCLUSIONS: We envision that the BeyeOMARKER study will demonstrate the feasibility of early AD detection based on blood- and eye-based biomarkers in alternative screening settings, and will improve our understanding of the eye-brain connection. TRIAL REGISTRATION: The BeyeOMARKER study (Eudamed CIV ID: CIV-NL-23-09-044086; registration date: 19th of March 2024) is approved by the ethical review board of the Amsterdam UMC.


Asunto(s)
Enfermedad de Alzheimer , Biomarcadores , Diagnóstico Precoz , Humanos , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/diagnóstico por imagen , Biomarcadores/sangre , Estudios Prospectivos , Masculino , Femenino , Anciano , Proteínas tau/sangre , Persona de Mediana Edad , Estudios Longitudinales , Péptidos beta-Amiloides/sangre , Oftalmopatías/diagnóstico , Oftalmopatías/sangre , Oftalmopatías/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Estudios de Cohortes
19.
Transl Vis Sci Technol ; 13(8): 40, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39177992

RESUMEN

Purpose: To determine endothelial cell density (ECD) from real-world donor cornea endothelial cell (EC) images using a self-supervised deep learning segmentation model. Methods: Two eye banks (Eversight, VisionGift) provided 15,138 single, unique EC images from 8169 donors along with their demographics, tissue characteristics, and ECD. This dataset was utilized for self-supervised training and deep learning inference. The Cornea Image Analysis Reading Center (CIARC) provided a second dataset of 174 donor EC images based on image and tissue quality. These images were used to train a supervised deep learning cell border segmentation model. Evaluation between manual and automated determination of ECD was restricted to the 1939 test EC images with at least 100 cells counted by both methods. Results: The ECD measurements from both methods were in excellent agreement with rc of 0.77 (95% confidence interval [CI], 0.75-0.79; P < 0.001) and bias of 123 cells/mm2 (95% CI, 114-131; P < 0.001); 81% of the automated ECD values were within 10% of the manual ECD values. When the analysis was further restricted to the cropped image, the rc was 0.88 (95% CI, 0.87-0.89; P < 0.001), bias was 46 cells/mm2 (95% CI, 39-53; P < 0.001), and 93% of the automated ECD values were within 10% of the manual ECD values. Conclusions: Deep learning analysis provides accurate ECDs of donor images, potentially reducing analysis time and training requirements. Translational Relevance: The approach of this study, a robust methodology for automatically evaluating donor cornea EC images, could expand the quantitative determination of endothelial health beyond ECD.


Asunto(s)
Endotelio Corneal , Donantes de Tejidos , Humanos , Endotelio Corneal/citología , Femenino , Masculino , Persona de Mediana Edad , Recuento de Células/métodos , Adulto , Anciano , Aprendizaje Profundo , Bancos de Ojos , Procesamiento de Imagen Asistido por Computador/métodos , Adulto Joven , Adolescente , Anciano de 80 o más Años
20.
J Org Chem ; 89(18): 13450-13456, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39195724

RESUMEN

Aminated nitrogen heterocycles are valuable motifs across numerous chemical industries, perhaps most notably in small molecule drug discovery. While numerous strategies for installing nitrogen atoms onto azaarenes exist, most require prefunctionalization and methods for direct C-H amination are almost entirely limited to position C2. Herein, we report a method for the direct C2 and C4 C-H amination of fused azaarenes via in situ activation with a bispyridine-ligated I(III) reagent, [(Py)2IPh]2OTf, or Py-HVI. Unlike commonly used N-oxide chemistry, the method requires no preoxidation of the azaarene and provides unprecedented direct access to C4 amination products. The resulting N-heterocyclic pyridinium salts can be isolated via simple trituration. The free amine can be liberated under mild Zincke aminolysis, or the amination and cleavage can be telescoped to a one-pot process. The scope of the method is broad; the conditions are mild and operationally simple, and the aminated products are produced in good to excellent yields. Computational studies provide insights into the mechanism of activation, which involves an unusual direct nucleophilic functionalization of an I(III) ligand, as well as a kinetic basis for the observed C2 and C4 amination products.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...