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1.
J Gen Intern Med ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020232

RESUMO

BACKGROUND: There is growing concern that pulse oximeters are routinely less accurate in hospitalized patients with darker skin pigmentation, in turn increasing risk of undetected (occult) hypoxemia and adverse clinical outcomes. The aim of this systematic review and meta-analysis was to synthesize evidence on racial and ethnic disparities in occult hypoxemia prevalence and clinical impacts of undetected hypoxemia. METHODS: Ovid MEDLINE, Embase, and CINAHL databases were searched for relevant articles published through January 2024. Eligible studies must have been conducted among adults in inpatient or outpatient settings and report occult hypoxemia prevalence stratified by patient race or ethnicity, or clinical outcomes stratified by patient race or ethnicity and occult hypoxemia status. Screening for inclusion was conducted independently by two investigators. Data extraction and risk of bias assessment were conducted by one investigator then checked by a second. Outcome data were synthesized using random-effects meta-analyses. RESULTS: Fifteen primary studies met eligibility criteria and reported occult hypoxemia prevalence in 732,505 paired oximetry measurements from 207,464 hospitalized patients. Compared with White patients, occult hypoxemia is likely more common among Black patients (pooled prevalence ratio = 1.67, 95% CI 1.47 to 1.90) and among patients identifying as Asian, Latinx, Indigenous, multiracial, or other race or ethnicity (pooled prevalence ratio = 1.39, 95% CI 1.19 to 1.64). Findings from studies reporting clinical outcomes suggest that Black patients with undetected hypoxemia may experience poorer treatment delivery outcomes than White patients with undetected hypoxemia. No evidence was found from outpatient settings. DISCUSSION: This review and included primary studies rely on self-identified race or ethnicity, which may obscure variability in occult hypoxemia risk. Findings underscore that clinicians should be aware of the risk of occult hypoxemia in hospitalized patients with darker skin pigmentation. Moreover, oximetry data from included studies suggests that the accuracy of pulse oximeters could vary substantially from patient to patient and even within individual patients. TRIAL REGISTRATION: PROSPERO ( CRD42023402152 ).

2.
Basic Res Cardiol ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992300

RESUMO

Propionic acidemia (PA), arising from PCCA or PCCB variants, manifests as life-threatening cardiomyopathy and arrhythmias, with unclear pathophysiology. In this work, propionyl-CoA metabolism in rodent hearts and human pluripotent stem cell-derived cardiomyocytes was investigated with stable isotope tracing analysis. Surprisingly, gut microbiome-derived propionate rather than the propiogenic amino acids (valine, isoleucine, threonine, and methionine) or odd-chain fatty acids was found to be the primary cardiac propionyl-CoA source. In a Pcca-/-(A138T) mouse model and PA patients, accumulated propionyl-CoA and diminished acyl-CoA synthetase short-chain family member 3 impede hepatic propionate disposal, elevating circulating propionate. Prolonged propionate exposure induced significant oxidative stress in PCCA knockdown HL-1 cells and the hearts of Pcca-/-(A138T) mice. Additionally, Pcca-/-(A138T) mice exhibited mild diastolic dysfunction after the propionate challenge. These findings suggest that elevated circulating propionate may cause oxidative damage and functional impairment in the hearts of patients with PA.

3.
Artigo em Inglês | MEDLINE | ID: mdl-39017625

RESUMO

DISCLAIMER: In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. PURPOSE: Intravenous administration of the antiseizure medication lacosamide can be delayed given operational challenges related to short beyond-use-dating and controlled substance requirements. The purpose of this study was to describe the steps required to successfully transition from intravenous piggyback administration to intravenous push administration and demonstrate that workflow changes improved time to administration without compromising patient safety. METHODS: This multicenter study had 2 components; the first portion was a prospective description of the implementation and operationalization process, while the second was a retrospective cohort analysis comparing patients who received intravenous piggyback and intravenous push lacosamide. After the transition, the default administration route for adult patients for lacosamide doses of 400 mg or less was intravenous push. While the primary objective was to describe the implementation process, secondary objectives included comparison of time to administration and safety, using a composite and incidence of PR prolongation. RESULTS: Success in implementation and operationalization across a large health system was achieved by following a 6-month timeline. A total of 102 patients were included in the cohort study, with 869 individual administrations analyzed (519 intravenous piggyback and 350 intravenous push). Time from verification to administration was significantly decreased when comparing intravenous piggyback (median, 159 minutes) to intravenous push (median, 88 minutes) administrations (P = 0.008). No significant difference was found in the safety composite or PR prolongation. CONCLUSION: Transitioning intravenous lacosamide administration from piggyback to push administration is feasible and decreases time from verification to administration without increased incidence of adverse effects.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38884280

RESUMO

INTRODUCTION: Surgical techniques for sellar reconstruction include no reconstruction, use of synthetic materials, autologous grafts, and/or vascularized flaps. The aim of this study was to conduct a multi-center study comparing the efficacy and postoperative morbidity associated with different sellar reconstruction techniques. METHODS: A retrospective chart review of patients who underwent endoscopic transsphenoidal surgery for pituitary tumors from five participating sites between January 2021 and March 2023 was performed. The variables included demographics, tumor characteristics, reconstruction technique, postoperative cerebrospinal fluid leak (CSF) leak, and 22-item Sino-Nasal Outcome Test (SNOT-22) scores. Comparisons of postoperative complications, SNOT-22 scores, and duration of surgery by type of onlay reconstruction were evaluated using Fisher's exact test, analysis of variance, and Kruskal‒Wallis test. RESULTS: Five hundred and one patients were identified. The median tumor size was 2.1 cm, and 64% were non-functioning. Intraoperative CSF leak was identified in 38% of patients. A total of 89% of patients underwent onlay reconstruction: 49% were reconstructed with mucosal grafts, 35% with nasoseptal flaps, and 5% with other onlay techniques. Nasoseptal flaps were utilized more frequently in the setting of giant pituitary adenomas (>3 cm), medial cavernous sinus wall resection, and high-flow intraoperative CSF leaks. Cases who utilized mucosal grafts had an overall shorter operating time (median: 183 min vs. 240 min; p < 0.001). Five postoperative CSF leaks were identified, and therefore, statistical analysis could not be performed for this complication. CONCLUSION: The effectiveness and morbidity of different sellar reconstruction techniques are comparable. Vascularized flaps were utilized more frequently in the setting of larger tumors and high-flow intraoperative CSF leaks.

5.
Clin Kidney J ; 17(6): sfae156, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38915434

RESUMO

Climate change is responsible for ≈75% of extreme heat events throughout the world. Heat events are associated with an increased risk for acute kidney injury, which contributes to the development of chronic kidney disease (CKD) and cardiovascular events. Patients with CKD are especially vulnerable to heat stress for a variety of reasons. A disproportionate percentage of patients with CKD live in poverty; experience homelessness, mental illness or disabilities; work outside or are elderly, all demographics that overlap with populations most susceptible to episodes of extreme heat. Therefore, it is reasonable to conclude that exposure to episodes of extreme heat can lead to the progression of CKD and increases morbidity and mortality. Given these concerns, clinicians must be prepared to promptly recognize complications of heat in CKD patients and to help patients appropriately acclimate. We propose the following tips for clinicians to effectively care for their CKD patients during extreme heat days.

6.
PLoS One ; 19(6): e0304505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38889180

RESUMO

The role of macrophages in regulating the tumor microenvironment has spurned the exponential generation of nanoparticle targeting technologies. With the large amount of literature and the speed at which it is generated it is difficult to remain current with the most up-to-date literature. In this study we performed a topic modeling analysis of 854 abstracts of peer-reviewed literature for the most common usages of nanoparticle targeting of tumor associated macrophages (TAMs) in solid tumors. The data spans 20 years of literature, providing a broad perspective of the nanoparticle strategies. Our topic model found 6 distinct topics: Immune and TAMs, Nanoparticles, Imaging, Gene Delivery and Exosomes, Vaccines, and Multi-modal Therapies. We also found distinct nanoparticle usage, tumor types, and therapeutic trends across these topics. Moreover, we established that the topic model could be used to assign new papers into the existing topics, thereby creating a Living Review. This type of "birds-eye-view" analysis provides a useful assessment tool for exploring new and emerging themes within a large field.


Assuntos
Aprendizado de Máquina , Nanopartículas , Nanopartículas/química , Humanos , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/imunologia , Neoplasias , Microambiente Tumoral , Animais
8.
Angiogenesis ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727966

RESUMO

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease characterized by the development of arteriovenous malformations (AVMs) that can result in significant morbidity and mortality. HHT is caused primarily by mutations in bone morphogenetic protein receptors ACVRL1/ALK1, a signaling receptor, or endoglin (ENG), an accessory receptor. Because overexpression of Acvrl1 prevents AVM development in both Acvrl1 and Eng null mice, enhancing ACVRL1 expression may be a promising approach to development of targeted therapies for HHT. Therefore, we sought to understand the molecular mechanism of ACVRL1 regulation. We previously demonstrated in zebrafish embryos that acvrl1 is predominantly expressed in arterial endothelial cells and that expression requires blood flow. Here, we document that flow dependence exhibits regional heterogeneity and that acvrl1 expression is rapidly restored after reinitiation of flow. Furthermore, we find that acvrl1 expression is significantly decreased in mutants that lack the circulating Alk1 ligand, Bmp10, and that, in the absence of flow, intravascular injection of BMP10 or the related ligand, BMP9, restores acvrl1 expression in an Alk1-dependent manner. Using a transgenic acvrl1:egfp reporter line, we find that flow and Bmp10 regulate acvrl1 at the level of transcription. Finally, we observe similar ALK1 ligand-dependent increases in ACVRL1 in human endothelial cells subjected to shear stress. These data suggest that ligand-dependent Alk1 activity acts downstream of blood flow to maintain or enhance acvrl1 expression via a positive feedback mechanism, and that ALK1 activating therapeutics may have dual functionality by increasing both ALK1 signaling flux and ACVRL1 expression.

9.
Campbell Syst Rev ; 20(2): e1410, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38779333

RESUMO

This is a protocol for a systematic review and meta-analysis of research on mental health outcomes of abortion. Does abortion increase the risk of adverse mental health outcomes? That is the central question for this review. Our review aims to inform policy and practice by locating, critically appraising, and synthesizing empirical evidence on associations between abortion and subsequent mental health outcomes. Given the controversies surrounding this topic and the complex social, political, legal, and ideological contexts in which research and reviews on abortion are conducted, it is especially important to conduct this systematic review and meta-analysis with comprehensive, rigorous, unbiased, and transparent methods. We will include a variety of study designs to enhance understanding of studies' methodological strengths and weaknesses and to identify potential explanations for conflicting results. We will follow open science principles, providing access to our methods, measures, and results, and making data available for re-analysis.

10.
Zebrafish ; 21(2): 144-148, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38621210

RESUMO

Zebrafish eyes are anatomically similar to humans and have a higher percentage of cone photoreceptors more akin to humans than most rodent models, making them a beneficial model organism for studying vision. However, zebrafish are different in that they can regenerate their optic nerve after injury, which most other animals cannot. Vision in zebrafish and many other vertebrate animals, including humans, can be accessed using the optokinetic response (OKR), which is an innate eye movement that occurs when tracking an object. Because fish cannot use an eye chart, we utilize the OKR that is present in virtually all vertebrates to determine if a zebrafish has vision. To this end, we have developed an inexpensive OKR setup that uses 3D-printed and off-the-shelf parts. This setup has been designed and used by undergraduate researchers and is also scalable to a classroom laboratory setup. We demonstrate that this setup is fully functional for assessing the OKR, and we use it to illustrate the return of the OKR following optic nerve injury in adult zebrafish.


Assuntos
Nistagmo Optocinético , Peixe-Zebra , Humanos , Animais , Peixe-Zebra/fisiologia , Olho , Impressão Tridimensional
11.
BMJ Open ; 14(3): e080023, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38531581

RESUMO

OBJECTIVE: To identify and describe evidence on brief emergency department (ED)-delivered behavioural and care process interventions among patients presenting with suicide attempt or acute ideation, substance overdose or psychosis. DESIGN: We employed a scoping review design and searched multiple data sources, clinical trial registries and references lists through March 2023. We included English-language trials and rigorously designed observational studies. In alignment with scoping review guidelines, we did not assess the quality of included studies or rate the strength of evidence of intervention effectiveness. POPULATION: Our population of interest was adults presenting to the ED with suicidality (eg, attempt or acute ideation), any substance overdose or acute psychosis from a primary mental health condition. INTERVENTION: We included studies of brief behavioural or care process interventions delivered in the ED. OUTCOME MEASURES: Health outcomes (eg, symptom reduction), healthcare utilisation and harms. RESULTS: Our search identified 2034 potentially relevant articles. We included 40 studies: 3 systematic reviews and 39 primary studies. Most studies (n=34) examined ED interventions in patients with suicide attempt or suicidal ideation, while eight studies examined interventions in patients with opioid overdose. No studies examined ED interventions in patients with acute psychosis. Most suicide prevention studies reported that brief psychological, psychosocial or screening and triage interventions reduce suicide and suicide attempt following an ED visit. Most clinical trial interventions were multicomponent and included at least one follow-up. All substance overdose studies focused on opioids. These studies often contained medication and referral or consultation components. Multiple studies reported increases in substance use disorder treatment utilisation; evidence on repeat overdose events was limited. CONCLUSIONS: A wide range of multicomponent ED-delivered behavioural health interventions for suicidality and opioid use disorder show short-term improvement on primary outcomes such as suicide reattempt. Few studies on non-opioid substances and psychosis are available.


Assuntos
Overdose de Drogas , Transtornos Psicóticos , Adulto , Humanos , Saúde Mental , Transtornos Psicóticos/terapia , Tentativa de Suicídio/psicologia , Prevenção do Suicídio , Ideação Suicida , Serviço Hospitalar de Emergência
12.
ACR Open Rheumatol ; 6(6): 375-379, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38454175

RESUMO

OBJECTIVE: Mixed-methods research is valuable in health care to gain insights into patient perceptions. However, analyzing textual data from interviews can be time-consuming and require multiple analysts for investigator triangulation. This study aims to explore a novel approach to investigator triangulation in mixed-methods research by employing a large language model (LLM) for analyzing data from patient interviews. METHODS: This study compared the thematic analysis and survey generation performed by human investigators and ChatGPT-4, which uses GPT-4 as its backbone model, using data from an existing study that explored patient perceptions of barriers to arthroplasty. The human- and ChatGPT-4-generated themes and surveys were compared and evaluated based on their representation of salient themes from a predetermined topic guide. RESULTS: ChatGPT-4 generated analogous dominant themes and a comprehensive corresponding survey as the human investigators but in significantly less time. The survey questions generated by ChatGPT-4 were less precise than those developed by human investigators. The mixed-methods flowchart proposes integrating LLMs and human investigators as a supplementary tool for the preliminary thematic analysis of qualitative data and survey generation. CONCLUSION: By utilizing a combination of LLMs and human investigators through investigator triangulation, researchers may be able to conduct more efficient mixed-methods research to better understand patient perspectives. Ethical and qualitative implications of using LLMs should be considered.

13.
Mol Genet Metab ; 142(1): 108362, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38452609

RESUMO

Cerebral creatine deficiency syndromes (CCDS) are inherited metabolic phenotypes of creatine synthesis and transport. There are two enzyme deficiencies, guanidinoacetate methyltransferase (GAMT), encoded by GAMT and arginine-glycine amidinotransferase (AGAT), encoded by GATM, which are involved in the synthesis of creatine. After synthesis, creatine is taken up by a sodium-dependent membrane bound creatine transporter (CRTR), encoded by SLC6A8, into all organs. Creatine uptake is very important especially in high energy demanding organs such as the brain, and muscle. To classify the pathogenicity of variants in GAMT, GATM, and SLC6A8, we developed the CCDS Variant Curation Expert Panel (VCEP) in 2018, supported by The Clinical Genome Resource (ClinGen), a National Institutes of Health (NIH)-funded resource. We developed disease-specific variant classification guidelines for GAMT-, GATM-, and SLC6A8-related CCDS, adapted from the American College of Medical Genetics/Association of Molecular Pathology (ACMG/AMP) variant interpretation guidelines. We applied specific variant classification guidelines to 30 pilot variants in each of the three genes that have variants associated with CCDS. Our CCDS VCEP was approved by the ClinGen Sequence Variant Interpretation Working Group (SVI WG) and Clinical Domain Oversight Committee in July 2022. We curated 181 variants including 72 variants in GAMT, 45 variants in GATM, and 64 variants in SLC6A8 and submitted these classifications to ClinVar, a public variant database supported by the National Center for Biotechnology Information. Missense variants were the most common variant type in all three genes. We submitted 32 new variants and reclassified 34 variants with conflicting interpretations. We report specific phenotype (PP4) using a points system based on the urine and plasma guanidinoacetate and creatine levels, brain magnetic resonance spectroscopy (MRS) creatine level, and enzyme activity or creatine uptake in fibroblasts ranging from PP4, PP4_Moderate and PP4_Strong. Our CCDS VCEP is one of the first panels applying disease specific variant classification algorithms for an X-linked disease. The availability of these guidelines and classifications can guide molecular genetics and genomic laboratories and health care providers to assess the molecular diagnosis of individuals with a CCDS phenotype.


Assuntos
Amidinotransferases , Amidinotransferases/deficiência , Erros Inatos do Metabolismo dos Aminoácidos , Creatina , Creatina/deficiência , Guanidinoacetato N-Metiltransferase , Deficiência Intelectual , Transtornos do Desenvolvimento da Linguagem , Transtornos dos Movimentos/congênito , Proteínas do Tecido Nervoso , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/deficiência , Distúrbios da Fala , Humanos , Guanidinoacetato N-Metiltransferase/deficiência , Guanidinoacetato N-Metiltransferase/genética , Creatina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/genética , Amidinotransferases/genética , Amidinotransferases/metabolismo , Deficiência Intelectual Ligada ao Cromossomo X/genética , Deficiência Intelectual Ligada ao Cromossomo X/diagnóstico , Mutação , Encefalopatias Metabólicas Congênitas/genética , Encefalopatias Metabólicas Congênitas/diagnóstico , Fenótipo , Curadoria de Dados , Deficiências do Desenvolvimento
14.
Mol Genet Metab Rep ; 38: 101062, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38469099

RESUMO

Mitochondrial 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) synthase (mHS) deficiency is an autosomal recessive disorder of ketone body synthesis caused by biallelic pathogenic variants in HMGCS2. Clinical symptoms are precipitated by prolonged fasting and/or intercurrent illness with onset before the first year of life. Clinically, patients may present with hypo-/ non-ketotic hypoglycemia, metabolic acidosis, hyperammonemia, lethargy, hepatomegaly, and encephalopathy. During periods of decompensation, elevations of 4-hydroxy-6-methyl-2-pyrone (4-HMP), several hydroxylated hexanoic and hexenoic acid species, and medium-chain dicarboxylic acids in the absence of significant ketonuria may be observed in the urine organic acid profile. Abnormalities may also be observed in plasma which includes elevated acetylcarnitine (C2) and 3-hydroxybutyryl/3-hydroxyisobutyryl (C4-OH) carnitine. We report a patient who presented to the ED at 13 months of age with an undetectable point-of-care blood glucose level. Continuous infusion of dextrose-containing intravenous (IV) fluids were required to correct the hypoglycemia and routine chemistries were notable for an anion gap metabolic acidosis, transaminasemia, and elevated creatine kinase and lactate dehydrogenase. Urine and blood ketones were undetectable. Qualitative assessment of urine organic acids collected ∼46 and âˆ¼ 99 h post-admission were significant for mild elevations of 4-HMP and hydroxy-hexanoic and hydroxy-hexenoic acid species with a notable absence of ketones. Previously, biochemical abnormalities in urine have been shown to normalize in as few as 27 h after treatment giving providers a narrow window with which to obtain a critical sample. Direct communication of laboratory findings to the ordering provider guided the molecular testing and assisted in results interpretation to confirm the molecular diagnosis. Our case emphasizes the importance of collecting samples for biochemical analysis even if the critical period has been missed and acute metabolic decompensation seems to be resolved, as residual abnormalities observed in our patient greatly narrowed the differential diagnosis.

15.
bioRxiv ; 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38328175

RESUMO

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease characterized by the development of arteriovenous malformations (AVMs) that can result in significant morbidity and mortality. HHT is caused primarily by mutations in bone morphogenetic protein receptors ACVRL1/ALK1, a signaling receptor, or endoglin (ENG), an accessory receptor. Because overexpression of Acvrl1 prevents AVM development in both Acvrl1 and Eng null mice, enhancing ACVRL1 expression may be a promising approach to development of targeted therapies for HHT. Therefore, we sought to understand the molecular mechanism of ACVRL1 regulation. We previously demonstrated in zebrafish embryos that acvrl1 is predominantly expressed in arterial endothelial cells and that expression requires blood flow. Here, we document that flow dependence exhibits regional heterogeneity and that acvrl1 expression is rapidly restored after reinitiation of flow. Furthermore, we find that acvrl1 expression is significantly decreased in mutants that lack the circulating Alk1 ligand, Bmp10, and that BMP10 microinjection into the vasculature in the absence of flow enhances acvrl1 expression in an Alk1-dependent manner. Using a transgenic acvrl1:egfp reporter line, we find that flow and Bmp10 regulate acvrl1 at the level of transcription. Finally, we observe similar ALK1 ligand-dependent increases in ACVRL1 in human endothelial cells subjected to shear stress. These data suggest that Bmp10 acts downstream of blood flow to maintain or enhance acvrl1 expression via a positive feedback mechanism, and that ALK1 activating therapeutics may have dual functionality by increasing both ALK1 signaling flux and ACVRL1 expression.

16.
Pediatr Rep ; 16(1): 114-134, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38391000

RESUMO

Although child-centred care is increasingly referred to within the nursing literature, a clear definition of child-centred care and clarity around the concept is yet to be achieved. The objectives of this review were to examine the following: (1) What constitutes the concept of child-centred care in healthcare? (2) How has the concept of child-centred care developed? (3) What is the applicability of child-centred care and what are its limitations? (4) How does the concept of child-centred care benefit and inform children's healthcare? In total, 2984 papers were imported for screening, and, following the removal of duplicates and screening, 21 papers were included in the scoping review. The findings suggest that child-centred care is an emerging, ambiguous poorly defined concept; no clear consensus exists about what constitutes child-centred care. Although it seems antithetical to argue against child-centred care, little robust evidence was identified that demonstrates the impact and benefit of child-centred care. If child-centred care is to be a sustainable, convincing model to guide practice and compete with other models of care, it needs to establish robust evidence of its effectiveness, the impact on children and their families, as well as the wider impacts on the healthcare system.

17.
Sci Adv ; 10(8): eadj0975, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38381833

RESUMO

Breast cancer often metastasizes to bone, causing osteolytic lesions. Structural and biophysical changes are rarely studied yet are hypothesized to influence metastasis. We developed a mouse model of early bone metastasis and multimodal imaging to quantify cancer cell homing, bone (re)modeling, and onset of metastasis. Using tissue clearing and three-dimensional (3D) light sheet fluorescence microscopy, we located enhanced green fluorescent protein-positive cancer cells and small clusters in intact bones and quantified their size and spatial distribution. We detected early bone lesions using in vivo microcomputed tomography (microCT)-based time-lapse morphometry and revealed altered bone (re)modeling in the absence of detectable lesions. With a new microCT image analysis tool, we tracked the growth of early lesions over time. We showed that cancer cells home in all bone compartments, while osteolytic lesions are only detected in the metaphysis, a region of high (re)modeling. Our study suggests that higher rates of (re)modeling act as a driver of lesion formation during early metastasis.


Assuntos
Neoplasias Ósseas , Osteólise , Animais , Camundongos , Microtomografia por Raio-X/métodos , Neoplasias Ósseas/complicações , Neoplasias Ósseas/secundário , Osso e Ossos/diagnóstico por imagem , Osteólise/diagnóstico por imagem , Osteólise/etiologia , Osteólise/patologia , Modelos Animais de Doenças , Linhagem Celular Tumoral
18.
Angew Chem Int Ed Engl ; 63(13): e202316791, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38308859

RESUMO

Heparin and heparan sulfate (HS) are naturally occurring mammalian glycosaminoglycans, and their synthetic and semi-synthetic mimetics have attracted significant interest as potential therapeutics. However, understanding the mechanism of action by which HS, heparin, and HS mimetics have a biological effect is difficult due to their highly charged nature, broad protein interactomes, and variable structures. To address this, a library of novel single-entity dendritic mimetics conjugated to BODIPY, Fluorine-19 (19 F), and biotin was synthesized for imaging and localization studies. The novel dendritic scaffold allowed for the conjugation of labeling moieties without reducing the number of sulfated capping groups, thereby better mimicking the multivalent nature of HS-protein interactions. The 19 F labeled mimetics were assessed in phantom studies and were detected at concentrations as low as 5 mM. Flow cytometric studies using a fluorescently labeled mimetic showed that the compound associated with immune cells from tumors more readily than splenic counterparts and was directed to endosomal-lysosomal compartments within immune cells and cancer cells. Furthermore, the fluorescently labeled mimetic entered the central nervous system and was detectable in brain-infiltrating immune cells 24 hours after treatment. Here, we report the enabling methodology for rapidly preparing various labeled HS mimetics and molecular probes with diverse potential therapeutic applications.


Assuntos
Biotina , Compostos de Boro , Heparitina Sulfato , Animais , Heparitina Sulfato/química , Glicosaminoglicanos/metabolismo , Heparina/metabolismo , Mamíferos/metabolismo
19.
Nat Commun ; 15(1): 482, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38228616

RESUMO

Molecular-glue degraders are small molecules that induce a specific interaction between an E3 ligase and a target protein, resulting in the target proteolysis. The discovery of molecular glue degraders currently relies mostly on screening approaches. Here, we describe screening of a library of cereblon (CRBN) ligands against a panel of patient-derived cancer cell lines, leading to the discovery of SJ7095, a potent degrader of CK1α, IKZF1 and IKZF3 proteins. Through a structure-informed exploration of structure activity relationship (SAR) around this small molecule we develop SJ3149, a selective and potent degrader of CK1α protein in vitro and in vivo. The structure of SJ3149 co-crystalized in complex with CK1α + CRBN + DDB1 provides a rationale for the improved degradation properties of this compound. In a panel of 115 cancer cell lines SJ3149 displays a broad antiproliferative activity profile, which shows statistically significant correlation with MDM2 inhibitor Nutlin-3a. These findings suggest potential utility of selective CK1α degraders for treatment of hematological cancers and solid tumors.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Linhagem Celular , Neoplasias/tratamento farmacológico , Proteólise , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
20.
Physiol Genomics ; 56(3): 247-264, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38073491

RESUMO

Chronic intestinal inflammation is a poorly understood manifestation of cystic fibrosis (CF), which may be refractory to ion channel CF transmembrane conductance regulator (CFTR) modulator therapy. People with CF exhibit intestinal dysbiosis, which has the potential for stimulating intestinal and systemic inflammation. CFTR is expressed in organ epithelia, leukocytes, and other tissues. Here, we investigate the contribution of intestinal epithelium-specific loss of Cftr [iCftr knockout (KO)] to dysbiosis and inflammation in mice treated with either of two antiobstructive dietary regimens necessary to maintain CF mouse models [polyethylene glycol (PEG) laxative or a liquid diet (LiqD)]. Feces collected from iCftr KO mice and their wild-type (WT) sex-matched littermates were used to measure fecal calprotectin to evaluate inflammation and to perform 16S rRNA sequencing to characterize the gut microbiome. Fecal calprotectin was elevated in iCftr KO relative to WT mice that consumed either PEG or LiqD. PEG iCftr KO mice did not show a change in α diversity versus WT mice but demonstrated a significant difference in microbial composition (ß diversity) with included increases in the phylum Proteobacteria, the family Peptostreptococcaceae, four genera of Clostridia including C. innocuum, and the mucolytic genus Akkermansia. Fecal microbiome analysis of LiqD-fed iCftr KO mice showed both decreased α diversity and differences in microbial composition with increases in the Proteobacteria family Enterobacteriaceae, Firmicutes families Clostridiaceae and Peptostreptococcaceae, and enrichment of Clostridium perfringens, C. innocuum, C. difficile, mucolytic Ruminococcus gnavus, and reduction of Akkermansia. It was concluded that epithelium-specific loss of Cftr is a major driver of CF intestinal dysbiosis and inflammation with significant similarities to previous studies of pan Cftr KO mice.NEW & NOTEWORTHY Chronic intestinal inflammation is a manifestation of cystic fibrosis (CF), a disease caused by loss of the anion channel CF transmembrane conductance regulator (CFTR) that is expressed in many tissues. This study shows that intestinal epithelial cell-specific loss of CFTR [inducible Cftr knockout (KO)] in mice is sufficient to induce intestinal dysbiosis and inflammation. Experiments were performed on mice consuming two dietary regimens routinely used to prevent obstruction in CF mice.


Assuntos
Clostridioides difficile , Fibrose Cística , Obstrução Intestinal , Animais , Humanos , Camundongos , Clostridioides difficile/genética , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Disbiose/microbiologia , Expectorantes/uso terapêutico , Fezes , Inflamação , Complexo Antígeno L1 Leucocitário/uso terapêutico , Camundongos Endogâmicos CFTR , Camundongos Knockout , RNA Ribossômico 16S
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