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1.
Nature ; 621(7980): 857-867, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37730992

RESUMO

Speciation leads to adaptive changes in organ cellular physiology and creates challenges for studying rare cell-type functions that diverge between humans and mice. Rare cystic fibrosis transmembrane conductance regulator (CFTR)-rich pulmonary ionocytes exist throughout the cartilaginous airways of humans1,2, but limited presence and divergent biology in the proximal trachea of mice has prevented the use of traditional transgenic models to elucidate ionocyte functions in the airway. Here we describe the creation and use of conditional genetic ferret models to dissect pulmonary ionocyte biology and function by enabling ionocyte lineage tracing (FOXI1-CreERT2::ROSA-TG), ionocyte ablation (FOXI1-KO) and ionocyte-specific deletion of CFTR (FOXI1-CreERT2::CFTRL/L). By comparing these models with cystic fibrosis ferrets3,4, we demonstrate that ionocytes control airway surface liquid absorption, secretion, pH and mucus viscosity-leading to reduced airway surface liquid volume and impaired mucociliary clearance in cystic fibrosis, FOXI1-KO and FOXI1-CreERT2::CFTRL/L ferrets. These processes are regulated by CFTR-dependent ionocyte transport of Cl- and HCO3-. Single-cell transcriptomics and in vivo lineage tracing revealed three subtypes of pulmonary ionocytes and a FOXI1-lineage common rare cell progenitor for ionocytes, tuft cells and neuroendocrine cells during airway development. Thus, rare pulmonary ionocytes perform critical CFTR-dependent functions in the proximal airway that are hallmark features of cystic fibrosis airway disease. These studies provide a road map for using conditional genetics in the first non-rodent mammal to address gene function, cell biology and disease processes that have greater evolutionary conservation between humans and ferrets.


Assuntos
Fibrose Cística , Modelos Animais de Doenças , Furões , Pulmão , Transgenes , Animais , Humanos , Animais Geneticamente Modificados , Linhagem da Célula , Fibrose Cística/genética , Fibrose Cística/metabolismo , Fibrose Cística/patologia , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Furões/genética , Furões/fisiologia , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Pulmão/citologia , Pulmão/metabolismo , Pulmão/patologia , Traqueia/citologia , Transgenes/genética
2.
Proc Natl Acad Sci U S A ; 120(51): e2303075120, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38100414

RESUMO

Adipose tissue macrophages (ATM) are key players in the development of obesity and associated metabolic inflammation which contributes to systemic metabolic dysfunction. We here found that fibroblast activation protein α (FAP), a well-known marker of cancer-associated fibroblast, is selectively expressed in murine and human ATM among adipose tissue-infiltrating leukocytes. Macrophage FAP deficiency protects mice against diet-induced obesity and proinflammatory macrophage infiltration in obese adipose tissues, thereby alleviating hepatic steatosis and insulin resistance. Mechanistically, FAP specifically mediates monocyte chemokine protein CCL8 expression by ATM, which is further upregulated upon high-fat-diet (HFD) feeding, contributing to the recruitment of monocyte-derived proinflammatory macrophages with no effect on their classical inflammatory activation. CCL8 overexpression restores HFD-induced metabolic phenotypes in the absence of FAP. Moreover, macrophage FAP deficiency enhances energy expenditure and oxygen consumption preceding differential body weight after HFD feeding. Such enhanced energy expenditure is associated with increased levels of norepinephrine (NE) and lipolysis in white adipose tissues, likely due to decreased expression of monoamine oxidase, a NE degradation enzyme, by Fap-/- ATM. Collectively, our study identifies FAP as a previously unrecognized regulator of ATM function contributing to diet-induced obesity and metabolic inflammation and suggests FAP as a potential immunotherapeutic target against metabolic disorders.


Assuntos
Tecido Adiposo , Resistência à Insulina , Animais , Humanos , Camundongos , Tecido Adiposo/metabolismo , Dieta Hiperlipídica , Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Obesidade/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(29): e2205574119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858331

RESUMO

Intestinal barrier immunity is essential for controlling gut microbiota without eliciting harmful immune responses, while its defect contributes to the breakdown of intestinal homeostasis and colitis development. Chemerin, which is abundantly expressed in barrier tissues, has been demonstrated to regulate tissue inflammation via CMKLR1, its functional receptor. Several studies have reported the association between increased expression of chemerin-CMKLR1 and disease severity and immunotherapy resistance in inflammatory bowel disease (IBD) patients. However, the pathophysiological role of endogenous chemerin-CMKLR1 signaling in intestinal homeostasis remains elusive. We herein demonstrated that deficiency of chemerin or intestinal epithelial cell (IEC)-specific CMKLR1 conferred high susceptibility to microbiota-driven neutrophilic colon inflammation and subsequent tumorigenesis in mice following epithelial injury. Unexpectedly, we found that lack of chemerin-CMKLR1 signaling specifically reduced expression of lactoperoxidase (LPO), a peroxidase that is predominantly expressed in colonic ECs and utilizes H2O2 to oxidize thiocyanates to the antibiotic compound, thereby leading to the outgrowth and mucosal invasion of gram-negative bacteria and dysregulated CXCL1/2-mediated neutrophilia. Importantly, decreased LPO expression was causally linked to aggravated microbiota-driven colitis and associated tumorigenesis, as LPO supplementation could completely rescue such phenotypes in mice deficient in epithelial chemerin-CMKLR1 signaling. Moreover, epithelial chemerin-CMKLR1 signaling is necessary for early host defense against bacterial infection in an LPO-dependent manner. Collectively, our study reveals that the chemerin-CMKLR1/LPO axis represents an unrecognized immune mechanism that potentiates epithelial antimicrobial defense and restricts harmful colonic neutrophilia and suggests that LPO supplementation may be beneficial for microbiota dysbiosis in IBD patients with a defective innate antimicrobial mechanism.


Assuntos
Carcinogênese , Quimiocinas , Colite , Colo , Microbioma Gastrointestinal , Peptídeos e Proteínas de Sinalização Intercelular , Lactoperoxidase , Receptores de Quimiocinas , Animais , Carcinogênese/imunologia , Transformação Celular Neoplásica , Quimiocinas/genética , Quimiocinas/metabolismo , Colite/imunologia , Colite/microbiologia , Colo/imunologia , Colo/microbiologia , Peróxido de Hidrogênio/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Lactoperoxidase/metabolismo , Camundongos , Neutrófilos/imunologia , Receptores de Quimiocinas/genética , Receptores de Quimiocinas/metabolismo
4.
Proc Natl Acad Sci U S A ; 119(44): e2215921119, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36279432

RESUMO

Recent compelling results indicate possible links between neurotransmitters, intestinal mucosal IgA+ B cell responses, and immunoglobulin A nephropathy (IgAN) pathogenesis. Here, we demonstrated that γ-amino butyric acid (GABA) transporter-2 (GAT-2) deficiency induces intestinal germinal center (GC) B cell differentiation and worsens the symptoms of IgAN in a mouse model. Mechanistically, GAT-2 deficiency enhances GC B cell differentiation through activation of GABA-mammalian target of rapamycin complex 1 (mTORC1) signaling. In addition, IgAN patients have lower GAT-2 expression but higher activation of mTORC1 in blood B cells, and both are correlated with kidney function in IgAN patients. Collectively, this study describes GABA signaling-mediated intestinal mucosal immunity as a previously unstudied pathogenesis mechanism of IgAN and challenges the current paradigms of IgAN.


Assuntos
Glomerulonefrite por IGA , Camundongos , Animais , Ácido gama-Aminobutírico/metabolismo , Imunoglobulina A/metabolismo , Centro Germinativo/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Diferenciação Celular , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Mamíferos
5.
J Magn Reson Imaging ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167019

RESUMO

BACKGROUND: Accurately assessing 5-year recurrence rates is crucial for managing non-muscle-invasive bladder carcinoma (NMIBC). However, the European Organization for Research and Treatment of Cancer (EORTC) model exhibits poor performance. PURPOSE: To investigate whether integrating multiparametric MRI (mp-MRI) with clinical factors improves NMIBC 5-year recurrence risk assessment. STUDY TYPE: Retrospective. POPULATION: One hundred ninety-one patients (median age, 65 years; age range, 54-73 years; 27 females) underwent mp-MRI between 2011 and 2017, and received ≥5-year follow-ups. They were divided into a training cohort (N = 115) and validation/testing cohorts (N = 38 in each). Recurrence rates were 23.5% (27/115) in the training cohort and 23.7% (9/38) in both validation and testing cohorts. FIELD STRENGTH/SEQUENCE: 3-T, fast spin echo T2-weighted imaging (T2WI), single-shot echo planar diffusion-weighted imaging (DWI), and volumetric spoiled gradient echo dynamic contrast-enhanced (DCE) sequences. ASSESSMENT: Radiomics and deep learning (DL) features were extracted from the combined region of interest (cROI) including intratumoral and peritumoral areas on mp-MRI. Four models were developed, including clinical, cROI-based radiomics, DL, and clinical-radiomics-DL (CRDL) models. STATISTICAL TESTS: Student's t-tests, DeLong's tests with Bonferroni correction, receiver operating characteristics with the area under the curves (AUCs), Cox proportional hazard analyses, Kaplan-Meier plots, SHapley Additive ExPlanations (SHAP) values, and Akaike information criterion for clinical usefulness. A P-value <0.05 was considered statistically significant. RESULTS: The cROI-based CRDL model showed superior performance (AUC 0.909; 95% CI: 0.792-0.985) compared to other models in the testing cohort for assessing 5-year recurrence in NMIBC. It achieved the highest Harrell's concordance index (0.804; 95% CI: 0.749-0.859) for estimating recurrence-free survival. SHAP analysis further highlighted the substantial role (22%) of the radiomics features in NMIBC recurrence assessment. DATA CONCLUSION: Integrating cROI-based radiomics and DL features from preoperative mp-MRI with clinical factors could improve 5-year recurrence risk assessment in NMIBC. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.

6.
J Magn Reson Imaging ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822655

RESUMO

BACKGROUND: Ki-67 and human epidermal growth factor receptor 2 (HER2) are known oncogenes involved in bladder cancer (BCa) patient risk stratification. Preoperative assessment of their expression level can assist in clinical treatment decision-making. Recently, amide proton transfer-weighted (APTw) MRI has shown promising potential in the diagnosis of several malignancies. However, few studies reported the value of APTw imaging in evaluating Ki-67 and HER2 status of BCa. PURPOSE: To investigate the feasibility of APTw MRI in assessing the aggressive and proliferative potential regarding the expression levels of Ki-67 and HER2 in BCa. STUDY TYPE: Retrospective. SUBJECTS: 114 patients (mean age, 64.78 ± 11.93 [SD] years; 97 men) were studied. FIELD STRENGTH/SEQUENCE: APTw MRI acquired by a three-dimensional fast-spin-echo sequence at 3.0 T MRI system. ASSESSMENT: Patient pathologic findings, included histologic grade and the expression status of Ki-67 and HER2, were reviewed by one uropathologist. The APTw values of BCa were independently measured by two radiologists and were compared between high-/low-tumor grade group, high-/low-Ki-67 expression group, and high-/low-HER2 expression group. STATISTICAL TESTS: The interclass correlation coefficient, independent sample t-test, Mann-Whitney U test, Spearman's rank correlation, and receiver operating characteristic curve (ROC) analysis were used. P < 0.05 was considered statistically significant. RESULTS: Significantly higher APTw values were found in high-grade BCa patients (7.72% vs. 4.29%, P < 0.001), high-Ki-67 expression BCa patients (8.40% vs. 3.25%, P < 0.001) and HER2 positive BCa patients (8.24% vs. 5.40%, P = 0.001). APTw values were positively correlated with Ki-67 (r = 0.769) and HER2 (r = 0. 356) expression status. The area under the ROC curve of the APTw values for detecting Ki-67 and HER2 expression status were 0.883 (95% CI: 0.790-0.945) and 0.713 (95% CI: 0.592-0.816), respectively. DATA CONCLUSIONS: APTw MRI is a potential method to assess the biological and proliferation potential of BCa. TECHNICAL EFFICACY: Stage 2.

7.
Neuroepidemiology ; : 1-10, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38631321

RESUMO

INTRODUCTION: Healthcare costs and societal impact of myasthenia gravis (MG), a potentially life-threatening rare, chronic neuromuscular disease, are sparsely studied. We assessed healthcare resource utilization (HCRU) and associated costs among patients with newly diagnosed (ND) and preexisting (PE) MG in Sweden. METHODS: This observational, retrospective cohort study used data from four linkable Swedish nationwide population-based registries. Adult MG patients receiving pharmacological treatment for MG and having ≥24-month follow-up during the period January 1, 2010, to December 31, 2017, were included. RESULTS: A total of 1,275 patients were included in the analysis, of which 554 patients were categorized into the ND MG group and 721 into the PE MG group. Mean (±SD) age was 61.3 (±17.4) years, and 52.3% were female. In the first year post-diagnosis, ND patients had significantly higher utilization of acetylcholinesterase inhibitors (96.0% vs. 83.9%), corticosteroids (59.6% vs. 45.8%), thymectomy (12.1% vs. 0.7%), and plasma exchange (3.8% vs. 0.6%); had higher all-cause (70.9% vs. 35.8%) and MG-related (62.5% vs. 18.4%) hospitalization rates with 11 more hospitalization days (all p < 0.01) and an increased risk of hospitalization (odds ratio [95% CI] = 4.4 [3.43, 5.64]) than PE MG. In year 1 post-diagnosis, ND MG patients incurred EUR 7,302 (p < 0.01) higher total all-cause costs than PE MG, of which 84% were estimated to be MG-related and the majority (86%) were related to inpatient care. These results remained significant also after controlling for baseline demographics and comorbidities (p < 0.01). In year 2 post-diagnosis, the all-cause medical costs decreased by ∼55% for ND MG from year 1 and were comparable with PE MG. CONCLUSION: In this population-based study, MG patients required significantly more healthcare resources in year 1 post-diagnosis than PE MG primarily due to more pharmacological treatments, thymectomies, and associated hospitalizations. These findings highlight the need to better understand potential factors including disease characteristics associated with increased health resource use and costs and need for more efficacious treatments early in the disease course.

8.
Org Biomol Chem ; 22(6): 1176-1180, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38206312

RESUMO

A time-dependent, divergent synthesis of highly functionalized [1,2,3]triazolo[1,5-a]pyrazin-4(5H)-one (reaction time: 12 h) or 6,7-dihydro-[1,2,3]triazolo[1,5-a]pyrazin-4(5H)-one (reaction time: 2 h) scaffolds via a cascade azide-alkyne cycloaddition/hydroamination protocol is reported. The transformation features good functional group compatibility, broad substrate scope, high atom economy and avoidance of the use of transition-metal catalysts.

9.
Int J Hyperthermia ; 41(1): 2285705, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38269491

RESUMO

OBJECTIVE: The study aimed to compare the effectiveness and safety of ultrasound-guided microwave ablation (MWA) and percutaneous sclerotherapy (PS) for the treatment of large hepatic hemangioma (LHH). METHODS: This retrospective study included 96 patients who underwent MWA (n = 54) and PS (n = 42) as first-line treatment for LHH in three tertiary hospitals from January 2016 to December 2021. Primary outcomes were technique efficacy rate (volume reduction rate [VRR] > 50% at 12 months), symptom relief rate at 12 months and local tumor progression (LTP). Secondary outcomes included procedure time, major complications, treatment sessions, cost and one-, two-, three-year VRR. RESULTS: During a median follow-up of 36 months, the MWA group showed a higher technique efficacy rate (100% vs. 90.4%, p = .018) and symptom relief rate (100% vs. 80%, p = .123) than the PS group. The MWA group had fewer treatment sessions, higher one-, two- and three-year VRR, lower LTP rate (all p < .05), longer procedure time and higher treatment costs than the PS group (both p < .001). MWA shared a comparable major complications rate (1.8% vs. 2.4%, p = .432) with PS. After multivariate analysis, the lesion's heterogeneity and maximum diameter >8.1 cm were independent risk factors for LTP (all p < .05). In the PS group, lesions with a cumulative dose of bleomycin > 0.115 mg/cm3 had a lower risk of LTP (p = .006). CONCLUSIONS: Both MWA and PS treatments for large hepatic hemangioma are safe and effective, with MWA being superior in terms of efficacy.


Assuntos
Hemangioma , Neoplasias Hepáticas , Humanos , Escleroterapia , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Hemangioma/diagnóstico por imagem , Hemangioma/terapia , Neoplasias Hepáticas/terapia
10.
BMC Pregnancy Childbirth ; 24(1): 499, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054436

RESUMO

BACKGROUND: kangaroo care (KC), endorsed by the World Health Organization, is an evidence-based intervention that plays a pivotal role in mitigating preterm infant mortality and morbidity. However, this intervention has not been fully integrated into healthcare systems in China. This study aimed to gain insight into parents' perceptions and experiences of KC for preterm infants to contribute to the KC implementation on a larger scale. METHODS: This study employed a descriptive qualitative design, using face-to-face, semi-structured, in-depth interviews. Fifteen parents participating in KC for preterm infants in the neonatal intensive care units (NICUs) were purposively sampled from four hospitals across four cities in Zhejiang Province, China. Thematic analysis was employed to analyze the data. RESULTS: Four themes and twelve subthemes regarding the parents' perceptions and experiences about KC were identified. The four themes included: (1) Low motivation upon initial engagement with KC, (2) Dynamic fluctuations of emotional states during KC, (3) Unexpected gains, and (4) Barriers to participation. CONCLUSIONS: Parents' perceptions and experiences of KC was a staged process, with parents exhibiting distinct cognitive patterns and unique experiences at each stage. Overall, as KC progresses, parents' experiences tended to become increasingly positive, despite potential obstacles encountered along the way. To enhance the implementation of KC, healthcare providers could utilize prenatal and postnatal education programs. These programs aim to enhance the understanding of KC among parents of preterm infants, fostering sustained engagement in KC practices.


Assuntos
Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Método Canguru , Pais , Pesquisa Qualitativa , Humanos , Método Canguru/psicologia , China , Recém-Nascido , Feminino , Pais/psicologia , Masculino , Adulto , Percepção , Motivação
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