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1.
Endocrinology ; 165(8)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946397

RESUMO

Uterine leiomyoma or fibroids are prevalent noncancerous tumors of the uterine muscle layer, yet their origin and development remain poorly understood. We analyzed RNA expression profiles of 15 epigenetic mediators in uterine fibroids compared to myometrium using publicly available RNA sequencing (RNA-seq) data. To validate our findings, we performed RT-qPCR on a separate cohort of uterine fibroids targeting these modifiers confirming our RNA-seq data. We then examined protein profiles of key N6-methyladenosine (m6A) modifiers in fibroids and their matched myometrium, showing no significant differences in concordance with our RNA expression profiles. To determine RNA modification abundance, mRNA and small RNA from fibroids and matched myometrium were analyzed by ultra-high performance liquid chromatography-mass spectrometry identifying prevalent m6A and 11 other known modifiers. However, no aberrant expression in fibroids was detected. We then mined a previously published dataset and identified differential expression of m6A modifiers that were specific to fibroid genetic subtype. Our analysis also identified m6A consensus motifs on genes previously identified to be dysregulated in uterine fibroids. Overall, using state-of-the-art mass spectrometry, RNA expression, and protein profiles, we characterized and identified differentially expressed m6A modifiers in relation to driver mutations. Despite the use of several different approaches, we identified limited differential expression of RNA modifiers and associated modifications in uterine fibroids. However, considering the highly heterogenous genomic and cellular nature of fibroids, and the possible contribution of single molecule m6A modifications to fibroid pathology, there is a need for greater in-depth characterization of m6A marks and modifiers in a larger and diverse patient cohort.


Assuntos
Adenosina , Leiomioma , Neoplasias Uterinas , Leiomioma/genética , Leiomioma/metabolismo , Humanos , Feminino , Adenosina/análogos & derivados , Adenosina/metabolismo , Neoplasias Uterinas/genética , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/patologia , Miométrio/metabolismo , Miométrio/patologia , Pessoa de Meia-Idade , Adulto , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , RNA/genética , RNA/metabolismo , Processamento Pós-Transcricional do RNA , Epigênese Genética
2.
J Clin Invest ; 134(12)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38950310

RESUMO

In utero gene editing (IUGE) is a potential treatment for inherited diseases that cause pathology before or soon after birth. Preexisting immunity to adeno-associated virus (AAV) vectors and Cas9 endonuclease may limit postnatal gene editing. The tolerogenic fetal immune system minimizes a fetal immune barrier to IUGE. However, the ability of maternal immunity to limit fetal gene editing remains a question. We investigated whether preexisting maternal immunity to AAV or Cas9 impairs IUGE. Using a combination of fluorescent reporter mice and a murine model of a metabolic liver disease, we demonstrated that maternal anti-AAV IgG antibodies were efficiently transferred from dam to fetus and impaired IUGE in a maternal titer-dependent fashion. By contrast, maternal cellular immunity was inefficiently transferred to the fetus, and neither maternal cellular nor humoral immunity to Cas9 impaired IUGE. Using human umbilical cord and maternal blood samples collected from mid- to late-gestation pregnancies, we demonstrated that maternal-fetal transmission of anti-AAV IgG was inefficient in midgestation compared with term, suggesting that the maternal immune barrier to clinical IUGE would be less relevant at midgestation. These findings support immunologic advantages for IUGE and inform maternal preprocedural testing protocols and exclusion criteria for future clinical trials.


Assuntos
Dependovirus , Edição de Genes , Animais , Feminino , Dependovirus/genética , Dependovirus/imunologia , Camundongos , Gravidez , Humanos , Imunoglobulina G/imunologia , Imunoglobulina G/genética , Imunoglobulina G/sangue , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/imunologia , Vetores Genéticos/imunologia , Troca Materno-Fetal/imunologia , Troca Materno-Fetal/genética , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Sistemas CRISPR-Cas , Feto/imunologia , Imunidade Materno-Adquirida/imunologia
3.
J Foot Ankle Surg ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964708

RESUMO

The aim of the study was to compare preoperative factors and postoperative outcomes in patients with heel ulcerations that primarily had a transtibial (below the knee) amputation (N=38) versus vertical contour calcanectomy (n=62). The groups had no statistical difference between their Charlson Comorbidity Index Score, a prognostic score of ten-year survival in patients with multiple comorbidities. The odds of primary closure was 21.1 times higher in patients that underwent below knee amputation compared to patients that underwent vertical contour calcanectomy [OR 21.1 (95% CI 3.89-114.21)]. The odds of positive soft tissue culture at time of closure were 17.1 times higher for patients that underwent vertical contour calcanectomy [OR 17.1 (95% CI 5.40-54.16)]. The odds of a patent posterior tibial artery was 3.3 times higher for patients that underwent vertical contour calcanectomy [OR 3.3 (95% 1.09-10.09)]. The secondary aim of the study was to evaluate preoperative factors and postoperative outcomes in patients with failed vertical contour calcanectomy, defined as needing a below knee amputation. The odds of vertical contour calcanectomy failure was 13.7 times higher in male patients [OR 13.7 (95% CI 1.80-107.60)]. Vertical contour calcanectomy failure was 5.7 times higher in patients with renal disease [OR 5.7 (95% CI 1.10-30.30)], and vertical contour calcanectomy failure was 16.1 times higher for patients who needed additional surgery post closure [OR 16.1 (95% CI 1.40-183.20)].

5.
Artigo em Inglês | MEDLINE | ID: mdl-38951363

RESUMO

PURPOSE: Micro-electrode recordings (MERs) are a key intra-operative modality used during deep brain stimulation (DBS) electrode implantation, which allow for a trained neurophysiologist to infer the anatomy in which the electrode is placed. As DBS targets are small, such inference is necessary to confirm that the electrode is correctly positioned. Recently, machine learning techniques have been used to augment the neurophysiologist's capability. The goal of this paper is to investigate the generalisability of these methods with respect to different clinical centres and training paradigms. METHODS: Five deep learning algorithms for binary classification of MER signals have been implemented. Three databases from two different clinical centres have also been collected with differing size, acquisition hardware, and annotation protocol. Each algorithm has initially been trained on the largest database, then either directly tested or fine-tuned on the smaller databases in order to estimate their generalisability. As a reference, they have also been trained from scratch on the smaller databases as well in order to estimate the effect of the differing database sizes and annotation systems. RESULTS: Each network shows significantly reduced performance (on the order of a 6.5% to 16.0% reduction in balanced accuracy) when applied out-of-distribution. This reduction can be ameliorated through fine-tuning the network on the new database through transfer learning. Although, even for these small databases, it appears that retraining from scratch may still offer equivalent performance as fine-tuning with transfer learning. However, this is at the expense of significantly longer training times. CONCLUSION: Generalisability is an important criterion for the success of machine learning algorithms in clinic. We have demonstrated that a variety of recent machine learning algorithms for MER classification are negatively affected by domain shift, but that this can be quickly ameliorated through simple transfer learning procedures that can be readily performed for new centres.

6.
J Vasc Surg ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38942398

RESUMO

OBJECTIVE: Outcomes for weekend surgical interventions are associated with higher rates of mortality and complications compared to weekday interventions. While prior investigations have reported the 'weekend effect' for carotid endarterectomy (CEA), this association remains unclear for Transcarotid Artery Revascularization (TCAR) and Transfemoral Carotid Artery Stenting (TFCAS). We investigated the weekend effect for all three carotid revascularization methods. METHODS: We queried the Vascular Quality Initiative (VQI) for patients undergoing CEA, TCAR, and TFCAS between 2016-2022. Chi-square and logistic regression modeling analyzed outcomes including in-hospital stroke, death, MI, and 30-day mortality by weekend vs. weekday intervention. Backward stepwise regression was utilized to identify significant confounding variables and were ultimately included in each final logistic regression model. Logistic regression of outcomes was substratified by symptomatic status. Secondary multivariable analysis compared outcomes between the three revascularization methods by weekend vs. weekday interventions. RESULTS: 155,962 procedures were analyzed including 103,790 CEA, 31,666 TCAR and 20,506 TFCAS. Of these, 1988 CEA, 246 TCAR and 820 TFCAS received weekend interventions. Logistic regression demonstrated no significant differences for TCAR, and increased odds of in-hospital stroke/death/MI for CEA [OR:1.31,(1.04-1.65)] and TFCAS [OR:1.46,(1.09-1.96)] weekend procedures. Asymptomatic TCAR patients had nearly triple the odds of 30-day mortality [OR:2.85,(1.06-7.68), P=0.038]. Similarly, odds of in-hospital death were nearly tripled for asymptomatic CEA [OR:2.89,(1.30-6.43), P=0.009] and asymptomatic TFCAS [OR:2.78,(1.34-5.76), P=0.006] patients. Secondary analysis demonstrated that CEA and TCAR had no significant differences for all outcomes. TFCAS was associated with increased odds of stroke and death compared to CEA and TCAR. CONCLUSION: In this observational cohort study, we found that weekend carotid revascularization is associated with increased odds of complications and mortality. Furthermore, asymptomatic weekend patients perform worse in the CEA and TFCAS procedural groups. Among the three revascularization methods, TFCAS is associated with the highest odds of perioperative stroke and mortality. As such, our findings suggest that TFCAS procedures should be avoided over the weekend, in favor of CEA or TCAR. In patients who are poor candidates for CEA, TCAR offers the lowest morbidity and mortality for weekend procedures.

7.
Genes (Basel) ; 15(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38927713

RESUMO

Members of the SOX (SRY-related HMG box) family of transcription factors are crucial for embryonic development and cell fate determination. This review investigates the role of SOX3 in cancer, as aberrations in SOX3 expression have been implicated in several cancers, including osteosarcoma, breast, esophageal, endometrial, ovarian, gastric, hepatocellular carcinomas, glioblastoma, and leukemia. These dysregulations modulate key cancer outcomes such as apoptosis, epithelial-mesenchymal transition (EMT), invasion, migration, cell cycle, and proliferation, contributing to cancer development. SOX3 exhibits varied expression patterns correlated with clinicopathological parameters in diverse tumor types. This review aims to elucidate the nuanced role of SOX3 in tumorigenesis, correlating its expression with clinical and pathological characteristics in cancer patients and cellular modelsBy providing a comprehensive exploration of SOX3 involvement in cancer, this review underscores the multifaceted role of SOX3 across distinct tumor types. The complexity uncovered in SOX3 function emphasizes the need for further research to unravel its full potential in cancer therapeutics.


Assuntos
Carcinogênese , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Carcinogênese/genética , Transição Epitelial-Mesenquimal/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Regulação Neoplásica da Expressão Gênica , Animais
8.
HGG Adv ; 5(3): 100315, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38845201

RESUMO

Deciphering the genetic basis of prostate-specific antigen (PSA) levels may improve their utility for prostate cancer (PCa) screening. Using genome-wide association study (GWAS) summary statistics from 95,768 PCa-free men, we conducted a transcriptome-wide association study (TWAS) to examine impacts of genetically predicted gene expression on PSA. Analyses identified 41 statistically significant (p < 0.05/12,192 = 4.10 × 10-6) associations in whole blood and 39 statistically significant (p < 0.05/13,844 = 3.61 × 10-6) associations in prostate tissue, with 18 genes associated in both tissues. Cross-tissue analyses identified 155 statistically significantly (p < 0.05/22,249 = 2.25 × 10-6) genes. Out of 173 unique PSA-associated genes across analyses, we replicated 151 (87.3%) in a TWAS of 209,318 PCa-free individuals from the Million Veteran Program. Based on conditional analyses, we found 20 genes (11 single tissue, nine cross-tissue) that were associated with PSA levels in the discovery TWAS that were not attributable to a lead variant from a GWAS. Ten of these 20 genes replicated, and two of the replicated genes had colocalization probability of >0.5: CCNA2 and HIST1H2BN. Six of the 20 identified genes are not known to impact PCa risk. Fine-mapping based on whole blood and prostate tissue revealed five protein-coding genes with evidence of causal relationships with PSA levels. Of these five genes, four exhibited evidence of colocalization and one was conditionally independent of previous GWAS findings. These results yield hypotheses that should be further explored to improve understanding of genetic factors underlying PSA levels.

10.
ACS Med Chem Lett ; 15(6): 814-821, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38894923

RESUMO

RNAs are increasingly considered valuable therapeutic targets, and the development of methods to identify and validate both RNA targets and ligands is more important than ever. Here, we utilized a bioinformatic approach to identify a hairpin-containing RNA G-quadruplex (rG4) in the 5' untranslated region (5' UTR) of DHX15 mRNA. By using a novel competitive small molecule microarray (SMM) approach, we identified a compound that specifically binds to the DHX15 rG4 (K D = 12.6 ± 1.0 µM). This rG4 directly impacts translation of a DHX15 reporter mRNA in vitro, and binding of our compound (F1) to the structure inhibits translation up to 57% (IC50 = 22.9 ± 3.8 µM). This methodology allowed us to identify and target the mRNA of a cancer-relevant helicase with no known inhibitors. Our target identification method and the novelty of our screening approach make our work informative for future development of novel small molecule cancer therapeutics for RNA targets.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38874653

RESUMO

PURPOSE: Frontotemporal lobe dementia (FTD) results from the degeneration of the frontal and temporal lobes. It can manifest in several different ways, leading to the definition of variants characterised by their distinctive symptomatologies. As these variants are detected based on their symptoms, it can be unclear if they represent different types of FTD or different symptomatological axes. The goal of this paper is to investigate this question with a constrained cohort of FTD patients in order to see if the heterogeneity within this cohort can be inferred from medical images rather than symptom severity measurements. METHODS: An ensemble of convolutional neural networks (CNNs) is used to classify diffusion tensor images collected from two databases consisting of 72 patients with behavioural variant FTD and 120 healthy controls. FTD biomarkers were found using voxel-based analysis on the sensitivities of these CNNs. Sparse principal components analysis (sPCA) is then applied on the sensitivities arising from the patient cohort in order to identify the axes along which the patients express these biomarkers. Finally, this is correlated with their symptom severity measurements in order to interpret the clinical presentation of each axis. RESULTS: The CNNs result in sensitivities and specificities between 83 and 92%. As expected, our analysis determines that all the robust biomarkers arise from the frontal and temporal lobes. sPCA identified four axes in terms of biomarker expression which are correlated with symptom severity measurements. CONCLUSION: Our analysis confirms that behavioural variant FTD is not a singular type or spectrum of FTD, but rather that it has multiple symptomatological axes that relate to distinct regions of the frontal and temporal lobes. This analysis suggests that medical images can be used to understand the heterogeneity of FTD patients and the underlying anatomical changes that lead to their different clinical presentations.

13.
Vet J ; 306: 106155, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38838769

RESUMO

Penile squamous cell carcinomas (SCCs) are common, potentially life-threatening neoplasms of horses. They are well-recognized to be caused by Equus caballus papillomavirus (EcPV) type 2, although EcPV2 cannot be detected in all cases. A 23-year-old standardbred gelding developed multiple penile in situ and invasive SCCs that contained histological evidence of PV infection. By using both consensus and specific PCR primers, these lesions were found to contain EcPV7 DNA, but not DNA from EcPV2 or any other PV type. To determine how frequently EcPV7 is present in equine penile SCCs, specific primers were used to detect EcPV2 and EcPV7 in a series of 20 archived samples. EcPV7 was the only PV detected in one, both EcPV2 and 7 were detected in five, and only EcPV2 was detected in 14 SCCs. EcPV7 DNA was also detected in three of 10 archived oropharyngeal SCCs, although only as a co- infection with EcPV2. This is the first report of EcPV7 causing disease in horses. These results suggest EcPV7 could cause a subset of equine penile SCCs, and this is the first evidence that PV types other than EcPV2 can cause these neoplasms. The detection of EcPV7 in the oropharyngeal SCCs suggests a potential role of this PV type in the development of these SCCs. There were no clinical or histological features that differentiated lesions containing EcPV7 DNA from those containing EcPV2 DNA. If EcPV7 causes a proportion of equine penile SCCs, vaccines to prevent EcPV2 infection may not prevent all equine penile SCCs.

14.
FASEB J ; 38(11): e23710, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38822676

RESUMO

Steroidogenic tissues contain cytosolic lipid droplets that are important for steroidogenesis. Perilipin 2 (PLIN2), a structural coat protein located on the surface of lipid droplets in mammalian cells, plays a crucial role in regulating lipid droplet formation and contributing to various cellular processes such as lipid storage and energy homeostasis. Herein, we examine the role that PLIN2 plays in regulating progesterone synthesis in the bovine corpus luteum. Utilizing gene array databases and Western blotting, we have delineated the expression pattern of PLIN2 throughout the follicular to luteal transition. Our findings reveal the presence of PLIN2 in both ovarian follicular and steroidogenic luteal cells, demonstrating an increase in its levels as follicular cells transition into the luteal phase. Moreover, the depletion of PLIN2 via siRNA enhanced progesterone production in small luteal cells, whereas adenovirus-mediated overexpression of both PLIN2 and Perilipin 3 (PLIN3) induced an increase in cytosolic lipid droplet accumulation and decreased hormone-induced progesterone synthesis in these cells. Lastly, in vivo administration of the luteolytic hormone prostaglandin F2α resulted in an upregulation of PLIN2 mRNA and protein expression, accompanied by a decline in serum progesterone. Our findings highlight the pivotal role of PLIN2 in regulating progesterone synthesis in the bovine corpus luteum, as supported by its dynamic expression pattern during the follicular to luteal transition and its responsiveness to luteotropic and luteolytic hormones. We suggest PLIN2 as a potential therapeutic target for modulating luteal function.


Assuntos
Células Lúteas , Perilipina-2 , Progesterona , Animais , Feminino , Bovinos , Progesterona/metabolismo , Perilipina-2/metabolismo , Perilipina-2/genética , Células Lúteas/metabolismo , Gotículas Lipídicas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Perilipina-3/metabolismo , Corpo Lúteo/metabolismo , Células Cultivadas
15.
Age Ageing ; 53(6)2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38877714

RESUMO

Peripheral artery disease (PAD) is the lower limb manifestation of systemic atherosclerotic disease. PAD may initially present with symptoms of intermittent claudication, whilst chronic limb-threatening ischaemia (CLTI), the end stage of PAD, presents with rest pain and/or tissue loss. PAD is an age-related condition present in over 10% of those aged ≥65 in high-income countries. Guidelines regarding definition, diagnosis and staging of PAD and CLTI have been updated to reflect the changing patterns and presentations of disease given the increasing prevalence of diabetes. Recent research has changed guidelines on optimal medical therapy, with low-dose anticoagulant plus aspirin recommended in some patients. Recently published randomised trials highlight where bypass-first or endovascular-first approaches may be optimal in infra-inguinal disease. New techniques in endovascular surgery have increased minimally invasive options for ever more complex disease. Increasing recognition has been given to the complexity of patients with CLTI where a high prevalence of both frailty and cognitive impairment are present and a significant burden of multi-morbidity and polypharmacy. Despite advances in minimally invasive revascularisation techniques and reduction in amputation incidence, survival remains poor for many with CLTI. Shared decision-making is essential, and conservative management is often appropriate for older patients. There is emerging evidence of the benefit of specialist geriatric team input in the perioperative management of older patients undergoing surgery for CLTI. Recent UK guidelines now recommend screening for frailty, cognitive impairment and delirium in older vascular surgery patients as well as recommending all vascular surgery services have support and input from specialist geriatrics teams.


Assuntos
Doença Arterial Periférica , Humanos , Doença Arterial Periférica/terapia , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/epidemiologia , Idoso , Procedimentos Endovasculares/métodos , Fatores de Risco , Isquemia Crônica Crítica de Membro/epidemiologia , Isquemia Crônica Crítica de Membro/terapia , Isquemia Crônica Crítica de Membro/diagnóstico , Isquemia Crônica Crítica de Membro/cirurgia , Procedimentos Cirúrgicos Vasculares , Fatores Etários , Guias de Prática Clínica como Assunto
16.
Cells ; 13(11)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38891051

RESUMO

Respiratory viruses cause airway inflammation, resulting in epithelial injury and repair. miRNAs, including miR-149-5p, regulate different pathological conditions. We aimed to determine how miR-149-5p functions in regulating pro-inflammatory IL-6 and p63, key regulators of airway epithelial wound repair, in response to viral proteins in bronchial (BEAS-2B) and alveolar (A549) epithelial cells. BEAS-2B or A549 cells were incubated with poly (I:C, 0.5 µg/mL) for 48 h or SARS-CoV-2 spike protein-1 or 2 subunit (S1 or S2, 1 µg/mL) for 24 h. miR-149-5p was suppressed in BEAS-2B challenged with poly (I:C), correlating with IL-6 and p63 upregulation. miR-149-5p was down-regulated in A549 stimulated with poly (I:C); IL-6 expression increased, but p63 protein levels were undetectable. miR-149-5p remained unchanged in cells exposed to S1 or S2, while S1 transfection increased IL-6 expression in BEAS-2B cells. Ectopic over-expression of miR-149-5p in BEAS-2B cells suppressed IL-6 and p63 mRNA levels and inhibited poly (I:C)-induced IL-6 and p63 mRNA expressions. miR-149-5p directly suppressed IL-6 mRNA in BEAS-2B cells. Hence, BEAS-2B cells respond differently to poly (I:C), S1 or S2 compared to A549 cells. Thus, miR-149-5p dysregulation may be involved in poly (I:C)-stimulated but not S1- or S2-stimulated increased IL-6 production and p63 expression in BEAS-2B cells.


Assuntos
Células Epiteliais , Interleucina-6 , MicroRNAs , Poli I-C , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Interleucina-6/metabolismo , Células A549 , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/virologia , Poli I-C/farmacologia , SARS-CoV-2 , COVID-19/metabolismo , COVID-19/virologia , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Regulação da Expressão Gênica/efeitos dos fármacos
17.
Artigo em Inglês | MEDLINE | ID: mdl-38943376

RESUMO

Most melanomas progress from radial to vertical growth phase before spreading locoregionally and distally. Much is still unknown about the metabolic changes in the tumor cells and their microenvironment during this metastatic progression. We aimed to gain new insight into the molecular characteristics of melanoma in regard to spatial lipidomics to deliver new knowledge regarding tumor metastatic progression. We included 10 fresh tumor samples from 10 patients including two in situ melanomas, two invasive primary melanomas, and six metastatic melanomas (four in-transit metastases and two distant metastases). In addition, we analyzed four healthy skin controls from the same patients. Time-of-flight imaging secondary ion mass spectrometry (ToF-SIMS) enabled detailed spatial-lipidomics that could be directly correlated with conventional histopathological analysis of consecutive H&E-stained tissue sections. Significant differences in the lipid profiles were found in primary compared to metastatic melanomas, notably an increase in phosphatidylethanolamine lipids relative to phosphatidylinositol lipids and an increase in GM3 gangliosides in the metastatic samples. Furthermore, analysis of the data from in transit versus distant metastases samples highlighted that specific phospholipids, and a difference in the long versus shorter chain GM3 gangliosides, discriminated the metastatic routes. Further studies are warranted to verify these preliminary findings. Lipidomic changes could serve as a novel biomarker for tumor progression and even serve as a target for novel treatments. Furthermore, analyzing the lipid profiles could help to differentiate between primary and metastatic melanomas in challenging cases.

18.
J Biol Chem ; : 107482, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897567

RESUMO

Siglecs are cell surface receptors whose functions are tied to the binding of their sialoglycan ligands. Recently, we developed an optimized liposome formulation and used it to investigate the binding of human Siglecs (hSiglec) against a panel of gangliosides. Animal models, more specifically murine models, are used to understand human biology, however, species-specific differences can complicate the interpretation of the results. Herein, we used our optimized liposome formulation to dissect the interactions between murine Siglecs (mSiglecs) and gangliosides to assess the appropriateness of mSiglecs as a proxy to better understand the biological roles of hSiglec-ganglioside interactions. Using our optimized liposome formulation, we found that ganglioside binding is generally conserved between mice and humans with mSiglec-1, -E, -F, and -15 binding multiple gangliosides like their human counterparts. However, in contrast to the hSiglecs, we observed little to no binding between the mSiglecs and ganglioside GM1a. Detailed analysis of mSiglec-1 interacting with GM1a and its structural isomer, GM1b, suggests that mSiglec-1 preferentially binds α2-3-linked sialic acids presented from the terminal galactose residue. The ability of mSiglecs to interact or not interact with gangliosides, particularly GM1a, has implications for using mice to study neurodegenerative diseases, infections, and cancer, where interactions between Siglecs and glycolipids have been proposed to modulate these human diseases.

19.
Vet Sci ; 11(6)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38922022

RESUMO

The renin-angiotensin system (RAS) is increasingly being recognized to play a role in the tumor microenvironment, promoting tumor growth. Studies blocking a single part of the RAS have shown mixed results, possibly due to the existence of different bypass pathways and redundancy within the RAS. As such, multimodal blockade of the RAS has been developed to exert more complete inhibition of the RAS. The aim of the present study was to assess the safety of multimodal RAS blockade in dogs. Five dogs (four with appendicular osteosarcoma, one with oral malignant melanoma) were treated with atenolol, benazepril, curcumin, meloxicam, and metformin. The dogs underwent clinical examination, blood pressure measurement, and hematology and serum biochemistry tests performed at 0, 1, 3, 6, 9, and 12 weeks, then every 3 months thereafter. End-of-life decisions were made by the owners. None of the dogs developed hypotension. One dog had intermittent vomiting during the 64 weeks it was on the trial. One dog had a one-off increase in serum SDMA(symmetrical dimethylarginine) concentration. Dogs were euthanized at weeks 3 (osteosarcoma), 10 (osteosarcoma), 17 (osteosarcoma), and 26 (oral malignant melanoma), and one dog was still alive at the end of the trial at 64 weeks (osteosarcoma). This is the first assessment of multimodal blockade of the RAS in dogs, and the results suggest it causes only mild adverse effects in some animals. The efficacy of the treatment was not assessed due to the small number of dogs. This pilot study allows for future larger studies assessing multimodal RAS blockade for the treatment of canine cancer.

20.
AJR Am J Roentgenol ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775432

RESUMO

Peripheral nerve imaging provides information that can be critical to the diagnosis, staging, and management of peripheral neuropathies. MRI and ultrasound are the imaging modalities of choice for clinical evaluation of the peripheral nerves given their high soft tissue contrast and high resolution, respectively. This AJR Expert Panel Narrative Review describes MRI- and ultrasound-based techniques for peripheral nerve imaging; highlights considerations for imaging in the settings of trauma, entrapment syndromes, diffuse inflammatory neuropathies, and tumor; and discusses image-guided nerve interventions, focusing on nerve blocks and ablation.

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