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1.
Nat Immunol ; 18(9): 1016-1024, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28692065

RESUMO

Aberrant population expansion of follicular helper T cells (TFH cells) occurs in patients with lupus. An unanswered question is whether an altered repertoire of T cell antigen receptors (TCRs) is associated with such expansion. Here we found that the transcription factor Blimp-1 (encoded by Prdm1) repressed expression of the gene encoding cathepsin S (Ctss), a cysteine protease that cleaves invariant chains and produces antigenic peptides for loading onto major histocompatibility complex (MHC) class II molecules. The increased CTSS expression in dendritic cells (DCs) from female mice with dendritic cell-specific conditional knockout of Prdm1 (CKO mice) altered the presentation of antigen to CD4+ T cells. Analysis of complementarity-determining region 3 (CDR3) regions containing the ß-chain variable region (Vß) demonstrated a more diverse repertoire of TFH cells from female CKO mice than of those from wild-type mice. In vivo treatment of CKO mice with a CTSS inhibitor abolished the lupus-related phenotype and reduced the diversity of the TFH cell TCR repertoire. Thus, Blimp-1 deficiency in DCs led to loss of appropriate regulation of Ctss expression in female mice and thereby modulated antigen presentation and the TFH cell repertoire to contribute to autoimmunity.


Assuntos
Catepsinas/metabolismo , Células Dendríticas/metabolismo , Lúpus Eritematoso Sistêmico/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Fatores de Transcrição/genética , Animais , Anticorpos Antinucleares/imunologia , Apresentação de Antígeno/imunologia , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular , Proliferação de Células , DNA/imunologia , Células Dendríticas/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Rim/patologia , Lúpus Eritematoso Sistêmico/patologia , Ativação Linfocitária , Camundongos , Camundongos Knockout , Fator 1 de Ligação ao Domínio I Regulador Positivo , Receptores de Antígenos de Linfócitos T alfa-beta/genética
2.
Nature ; 612(7940): 534-539, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36477528

RESUMO

An effective vaccine is needed for the prevention and elimination of malaria. The only immunogens that have been shown to have a protective efficacy of more than 90% against human malaria are Plasmodium falciparum (Pf) sporozoites (PfSPZ) manufactured in mosquitoes (mPfSPZ)1-7. The ability to produce PfSPZ in vitro (iPfSPZ) without mosquitoes would substantially enhance the production of PfSPZ vaccines and mosquito-stage malaria research, but this ability is lacking. Here we report the production of hundreds of millions of iPfSPZ. iPfSPZ invaded human hepatocytes in culture and developed to mature liver-stage schizonts expressing P. falciparum merozoite surface protein 1 (PfMSP1) in numbers comparable to mPfSPZ. When injected into FRGhuHep mice containing humanized livers, iPfSPZ invaded the human hepatocytes and developed to PfMSP1-expressing late liver stage parasites at 45% the quantity of cryopreserved mPfSPZ. Human blood from FRGhuHep mice infected with iPfSPZ produced asexual and sexual erythrocytic-stage parasites in culture, and gametocytes developed to PfSPZ when fed to mosquitoes, completing the P. falciparum life cycle from infectious gametocyte to infectious gametocyte without mosquitoes or primates.


Assuntos
Plasmodium falciparum , Esporozoítos , Animais , Humanos , Camundongos , Culicidae/parasitologia , Malária/parasitologia , Malária/prevenção & controle , Vacinas Antimaláricas/biossíntese , Vacinas Antimaláricas/química , Malária Falciparum/parasitologia , Plasmodium falciparum/crescimento & desenvolvimento , Esporozoítos/crescimento & desenvolvimento , Esporozoítos/patogenicidade , Hepatócitos/parasitologia , Fígado/parasitologia , Proteína 1 de Superfície de Merozoito , Eritrócitos/parasitologia , Técnicas In Vitro
3.
Circulation ; 150(1): 7-18, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38808522

RESUMO

BACKGROUND: Current cardiovascular magnetic resonance sequences cannot discriminate between different myocardial extracellular space (ECSs), including collagen, noncollagen, and inflammation. We sought to investigate whether cardiovascular magnetic resonance radiomics analysis can distinguish between noncollagen and inflammation from collagen in dilated cardiomyopathy. METHODS: We identified data from 132 patients with dilated cardiomyopathy scheduled for an invasive septal biopsy who underwent cardiovascular magnetic resonance at 3 T. Cardiovascular magnetic resonance imaging protocol included native and postcontrast T1 mapping and late gadolinium enhancement (LGE). Radiomic features were computed from the midseptal myocardium, near the biopsy region, on native T1, extracellular volume (ECV) map, and LGE images. Principal component analysis was used to reduce the number of radiomic features to 5 principal radiomics. Moreover, a correlation analysis was conducted to identify radiomic features exhibiting a strong correlation (r>0.9) with the 5 principal radiomics. Biopsy samples were used to quantify ECS, myocardial fibrosis, and inflammation. RESULTS: Four histopathological phenotypes were identified: low collagen (n=20), noncollagenous ECS expansion (n=49), mild to moderate collagenous ECS expansion (n=42), and severe collagenous ECS expansion (n=21). Noncollagenous expansion was associated with the highest risk of myocardial inflammation (65%). Although native T1 and ECV provided high diagnostic performance in differentiating severe fibrosis (C statistic, 0.90 and 0.90, respectively), their performance in differentiating between noncollagen and mild to moderate collagenous expansion decreased (C statistic: 0.59 and 0.55, respectively). Integration of ECV principal radiomics provided better discrimination and reclassification between noncollagen and mild to moderate collagen (C statistic, 0.79; net reclassification index, 0.83 [95% CI, 0.45-1.22]; P<0.001). There was a similar trend in the addition of native T1 principal radiomics (C statistic, 0.75; net reclassification index, 0.93 [95% CI, 0.56-1.29]; P<0.001) and LGE principal radiomics (C statistic, 0.74; net reclassification index, 0.59 [95% CI, 0.19-0.98]; P=0.004). Five radiomic features per sequence were identified with correlation analysis. They showed a similar improvement in performance for differentiating between noncollagen and mild to moderate collagen (native T1, ECV, LGE C statistic, 0.75, 0.77, and 0.71, respectively). These improvements remained significant when confined to a single radiomic feature (native T1, ECV, LGE C statistic, 0.71, 0.70, and 0.64, respectively). CONCLUSIONS: Radiomic features extracted from native T1, ECV, and LGE provide incremental information that improves our capability to discriminate noncollagenous expansion from mild to moderate collagen and could be useful for detecting subtle chronic inflammation in patients with dilated cardiomyopathy.


Assuntos
Cardiomiopatia Dilatada , Matriz Extracelular , Humanos , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/patologia , Matriz Extracelular/patologia , Matriz Extracelular/metabolismo , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Colágeno/metabolismo , Miocárdio/patologia , Idoso , Fibrose , Imageamento por Ressonância Magnética/métodos , Biópsia , Análise de Componente Principal , Radiômica
4.
Mol Microbiol ; 121(4): 767-780, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38238886

RESUMO

Endoplasmic reticulum (ER) plays a pivotal role in the regulation of stress responses in multiple eukaryotic cells. However, little is known about the effector mechanisms that regulate stress responses in ER of the malaria parasite. Herein, we aimed to identify the importance of a transmembrane protein 33 (TMEM33)-domain-containing protein in life cycle of the rodent malaria parasite Plasmodium berghei. TMEM33 is an ER membrane-resident protein that is involved in regulating stress responses in various eukaryotic cells. A C-terminal tagged TMEM33 was localized in the ER throughout the blood and mosquito stages of development. Targeted deletion of TMEM33 confirmed its importance for asexual blood stages and ookinete development, in addition to its essential role for sporozoite infectivity in the mammalian host. Pilot scale analysis shows that the loss of TMEM33 results in the initiation of ER stress response and induction of autophagy. Our findings conclude an important role of TMEM33 in the development of all life cycle stages of the malaria parasite, which indicates its potential as an antimalarial target.


Assuntos
Malária , Plasmodium berghei , Animais , Retículo Endoplasmático/metabolismo , Estágios do Ciclo de Vida , Malária/parasitologia , Proteínas de Membrana/metabolismo , Plasmodium berghei/metabolismo , Proteínas de Protozoários/metabolismo
5.
FASEB J ; 38(4): e23480, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38354025

RESUMO

Accumulating evidence suggests that dysregulation of FOXO3a plays a significant role in the progression of various malignancies, including hepatocellular carcinoma (HCC). FOXO3a inactivation, driven by oncogenic stimuli, can lead to abnormal cell growth, suppression of apoptosis, and resistance to anticancer drugs. Therefore, FOXO3a emerges as a potential molecular target for the development of innovative treatments in the era of oncology. Linagliptin (LNGTN), a DPP-4 inhibitor known for its safe profile, has exhibited noteworthy anti-inflammatory and anti-oxidative properties in previous in vivo studies. Several potential molecular mechanisms have been proposed to explain these effects. However, the capacity of LNGTN to activate FOXO3a through AMPK activation has not been investigated. In our investigation, we examined the potential repurposing of LNGTN as a hepatoprotective agent against diethylnitrosamine (DENA) intoxication. Additionally, we assessed LNGTN's impact on apoptosis and autophagy. Following a 10-week administration of DENA, the liver underwent damage marked by inflammation and early neoplastic alterations. Our study presents the first experimental evidence demonstrating that LNGTN can reinstate the aberrantly regulated FOXO3a activity by elevating the nuclear fraction of FOXO3a in comparison to the cytosolic fraction, subsequent to AMPK activation. Moreover, noteworthy inactivation of NFκB induced by LNGTN was observed. These effects culminated in the initiation of apoptosis, the activation of autophagy, and the manifestation of anti-inflammatory, antiproliferative, and antiangiogenic outcomes. These effects were concomitant with improved liver function and microstructure. In conclusion, our findings open new avenues for the development of novel therapeutic strategies targeting the AMPK/FOXO3a signaling pathway in the management of chronic liver damage.


Assuntos
Carcinoma Hepatocelular , Inibidores da Dipeptidil Peptidase IV , Neoplasias Hepáticas , Animais , Ratos , Linagliptina/farmacologia , Proteínas Quinases Ativadas por AMP , Dietilnitrosamina/toxicidade , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/tratamento farmacológico , Hipoglicemiantes , Inibidores de Proteases , Antivirais , Anti-Inflamatórios
6.
J Biol Chem ; 299(1): 102750, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36436563

RESUMO

Type IIB receptor protein tyrosine phosphatases are cell surface transmembrane proteins that engage in cell adhesion via their extracellular domains (ECDs) and cell signaling via their cytoplasmic phosphatase domains. The ECDs of type IIB receptor protein tyrosine phosphatases form stable, homophilic, and trans interactions between adjacent cell membranes. Previous work has demonstrated how one family member, PTPRM, forms head-to-tail homodimers. However, as the interface was composed of residues conserved across the family, the determinants of homophilic specificity remain unknown. Here, we have solved the X-ray crystal structure of the membrane-distal N-terminal domains of PTPRK that form a head-to-tail dimer consistent with intermembrane adhesion. Comparison with the PTPRM structure demonstrates interdomain conformational differences that may define homophilic specificity. Using small-angle X-ray scattering, we determined the solution structures of the full-length ECDs of PTPRM and PTPRK, identifying that both are rigid extended molecules that differ in their overall long-range conformation. Furthermore, we identified one residue, W351, within the interaction interface that differs between PTPRM and PTPRK and showed that mutation to glycine, the equivalent residue in PTPRM, abolishes PTPRK dimer formation in vitro. This comparison of two members of the receptor tyrosine phosphatase family suggests that homophilic specificity is driven by a combination of shape complementarity and specific but limited sequence differences.


Assuntos
Proteínas Tirosina Fosfatases , Transdução de Sinais , Humanos , Adesão Celular , Linhagem Celular , Proteínas Tirosina Fosfatases/metabolismo , Tirosina
7.
Mod Pathol ; 37(1): 100369, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37890670

RESUMO

Generative adversarial networks (GANs) have gained significant attention in the field of image synthesis, particularly in computer vision. GANs consist of a generative model and a discriminative model trained in an adversarial setting to generate realistic and novel data. In the context of image synthesis, the generator produces synthetic images, whereas the discriminator determines their authenticity by comparing them with real examples. Through iterative training, the generator allows the creation of images that are indistinguishable from real ones, leading to high-quality image generation. Considering their success in computer vision, GANs hold great potential for medical diagnostic applications. In the medical field, GANs can generate images of rare diseases, aid in learning, and be used as visualization tools. GANs can leverage unlabeled medical images, which are large in size, numerous in quantity, and challenging to annotate manually. GANs have demonstrated remarkable capabilities in image synthesis and have the potential to significantly impact digital histopathology. This review article focuses on the emerging use of GANs in digital histopathology, examining their applications and potential challenges. Histopathology plays a crucial role in disease diagnosis, and GANs can contribute by generating realistic microscopic images. However, ethical considerations arise because of the reliance on synthetic or pseudogenerated images. Therefore, the manuscript also explores the current limitations and highlights the ethical considerations associated with the use of this technology. In conclusion, digital histopathology has seen an emerging use of GANs for image enhancement, such as color (stain) normalization, virtual staining, and ink/marker removal. GANs offer significant potential in transforming digital pathology when applied to specific and narrow tasks (preprocessing enhancements). Evaluating data quality, addressing biases, protecting privacy, ensuring accountability and transparency, and developing regulation are imperative to ensure the ethical application of GANs.


Assuntos
Corantes , Confiabilidade dos Dados , Humanos , Coloração e Rotulagem , Processamento de Imagem Assistida por Computador
8.
New Phytol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953386

RESUMO

C4 photosynthesis is a complex trait requiring multiple developmental and metabolic alterations. Despite this complexity, it has independently evolved over 60 times. However, our understanding of the transition to C4 is complicated by the fact that variation in photosynthetic type is usually segregated between species that diverged a long time ago. Here, we perform a genome-wide association study (GWAS) using the grass Alloteropsis semialata, the only known species to have C3, intermediate, and C4 accessions that recently diverged. We aimed to identify genomic regions associated with the strength of the C4 cycle (measured using δ13C), and the development of C4 leaf anatomy. Genomic regions correlated with δ13C include regulators of C4 decarboxylation enzymes (RIPK), nonphotochemical quenching (SOQ1), and the development of Kranz anatomy (SCARECROW-LIKE). Regions associated with the development of C4 leaf anatomy in the intermediate individuals contain additional leaf anatomy regulators, including those responsible for vein patterning (GSL8) and meristem determinacy (GIF1). The parallel recruitment of paralogous leaf anatomy regulators between A. semialata and other C4 lineages implies the co-option of these genes is context-dependent, which likely has implications for the engineering of the C4 trait into C3 species.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38493480

RESUMO

BACKGROUND: Congenital adrenal hyperplasia (CAH) encompasses a rare group of autosomal recessive disorders, characterised by enzymatic defects in steroidogenesis. Heterogeneity in management practices has been observed internationally. The International Congenital Adrenal Hyperplasia registry (I-CAH, https://sdmregistries.org/) was established to enable insights into CAH management and outcomes, yet its global adoption by endocrine centres remains unclear. DESIGN: We sought (1) to assess current practices amongst clinicians managing patients with CAH in the United Kingdom and Ireland, with a focus on choice of glucocorticoid, monitoring practices and screening for associated co-morbidities, and (2) to assess use of the I-CAH registry. MEASUREMENTS: We designed and distributed an anonymised online survey disseminated to members of the Society for Endocrinology and Irish Endocrine Society to capture management practices in the care of patients with CAH. RESULTS: Marked variability was found in CAH management, with differences between general endocrinology and subspecialist settings, particularly in glucocorticoid use, biochemical monitoring and comorbidity screening, with significant disparities in reproductive health monitoring, notably in testicular adrenal rest tumours (TARTs) screening (p = .002), sperm banking (p = .0004) and partner testing for CAH (p < .0001). Adoption of the I-CAH registry was universally low. CONCLUSIONS: Differences in current management of CAH continue to exist. It appears crucial to objectify if different approaches result in different long-term outcomes. New studies such as CaHASE2, incorporating standardised minimum datasets including replacement therapies and monitoring strategies as well as longitudinal data collection, are now needed to define best-practice and standardise care.

10.
Histopathology ; 85(1): 40-50, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38497348

RESUMO

AIMS: Oral epithelial dysplasia (OED) often exhibits a lymphocytic/lichenoid immune response (LIR), imparting histological resemblance to lichenoid mucositis and rendering diagnosis challenging. The clinical appearances of OED and lichenoid inflammatory processes are generally divergent, presenting as well-demarcated hyperkeratotic plaques and diffuse white and/or red mucosal change with variably prominent Wickham striae, respectively. To date, clinicopathological characterisation of OED with LIR, including clinical/gross appearance, has not been depicted. METHODS AND RESULTS: Cases of solitary OED with LIR for which a clinical photograph was available were identified in the authors' institutional files. Clinical and histological features were documented. In 44 identified cases, dysplasia was mild (19 of 44, 43.2%), moderate (19 of 44, 43.2%) and severe (six of 44, 13.6%). Clinically/grossly, all 44 cases (100.0%), presented as well-demarcated hyperkeratotic plaques lacking diffuse white-and-red mucosal change or Wickham striae. Histologically, OED with LIR exhibited numerous 'lichenoid' features beyond the lymphocytic band in the superficial lamina propria, including: leucocyte transmigration (38 of 44, 86.4%), spongiosis (37 of 44, 84.1%), Civatte/colloid bodies (36 of 44, 81.8%), basal cell degeneration (29 of 45, 65.9%), sawtooth rete ridges (11 of 44, 25.0%) and subepithelial clefting (7 of 44, 15.9%). CONCLUSIONS: Virtually any lichenoid histological feature may be seen in OED with LIR, representing a significant diagnostic pitfall. The typical clinical appearance of OED with LIR is of a well-demarcated hyperkeratotic plaque, characteristic of keratinising dysplasia and devoid of lichenoid features. This suggests that pathologist access to clinical photographs during diagnostic interpretation of biopsied white lesions, which represents opportunity to perform gross examination of the disease process, may reduce interobserver variability and improve diagnostic accuracy in this challenging differential diagnosis.


Assuntos
Linfócitos , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Linfócitos/patologia , Linfócitos/imunologia , Mucosa Bucal/patologia , Mucosa Bucal/imunologia , Idoso de 80 Anos ou mais , Adulto Jovem
11.
Glob Chang Biol ; 30(4): e17290, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38651789

RESUMO

Soil organic nitrogen (N) mineralization not only supports ecosystem productivity but also weakens carbon and N accumulation in soils. Recalcitrant (mainly mineral-associated organic matter) and labile (mainly particulate organic matter) organic materials differ dramatically in nature. Yet, the patterns and drivers of recalcitrant (MNrec) and labile (MNlab) organic N mineralization rates and their consequences on ecosystem N retention are still unclear. By collecting MNrec (299 observations) and MNlab (299 observations) from 57 15N tracing studies, we found that soil pH and total N were the master factors controlling MNrec and MNlab, respectively. This was consistent with the significantly higher rates of MNrec in alkaline soils and of MNlab in natural ecosystems. Interestingly, our analysis revealed that MNrec directly stimulated microbial N immobilization and plant N uptake, while MNlab stimulated the soil gross autotrophic nitrification which discouraged ammonium immobilization and accelerated nitrate production. We also noted that MNrec was more efficient at lower precipitation and higher temperatures due to increased soil pH. In contrast, MNlab was more efficient at higher precipitation and lower temperatures due to increased soil total N. Overall, we suggest that increasing MNrec may lead to a conservative N cycle, improving the ecosystem services and functions, while increasing MNlab may stimulate the potential risk of soil N loss.


Assuntos
Nitrogênio , Microbiologia do Solo , Solo , Solo/química , Nitrogênio/metabolismo , Plantas/metabolismo , Concentração de Íons de Hidrogênio , Nitrificação , Ciclo do Nitrogênio
12.
Glob Chang Biol ; 30(1): e17003, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37943245

RESUMO

Identifying tipping points in the relationship between aridity and gross nitrogen (N) cycling rates could show critical vulnerabilities of terrestrial ecosystems to climate change. Yet, the global pattern of gross N cycling response to aridity across terrestrial ecosystems remains unknown. Here, we collected 14,144 observations from 451 15 N-labeled studies and used segmented regression to identify the global threshold responses of soil gross N cycling rates and soil process-related variables to aridity index (AI), which decreases as aridity increases. We found on a global scale that increasing aridity reduced soil gross nitrate consumption but increased soil nitrification capacity, mainly due to reduced soil microbial biomass carbon (MBC) and N (MBN) and increased soil pH. Threshold response of gross N production and retention to aridity was observed across terrestrial ecosystems. In croplands, gross nitrification and extractable nitrate were inhibited with increasing aridity below the threshold AI ~0.8-0.9 due to inhibited ammonia-oxidizing archaea and bacteria, while the opposite was favored above this threshold. In grasslands, gross N mineralization and immobilization decreased with increasing aridity below the threshold AI ~0.5 due to decreased MBN, but the opposite was true above this threshold. In forests, increased aridity stimulated nitrate immobilization below the threshold AI ~1.0 due to increased soil C/N ratio, but inhibited ammonium immobilization above the threshold AI ~1.3 due to decreased soil total N and increased MBC/MBN ratio. Soil dissimilatory nitrate reduction to ammonium decreased with increasing aridity globally and in forests when the threshold AI ~1.4 was passed. Overall, we suggest that any projected increase in aridity in response to climate change is likely to reduce plant N availability in arid regions while enhancing it in humid regions, affecting the provision of ecosystem services and functions.


Assuntos
Compostos de Amônio , Ecossistema , Solo , Nitratos , Nitrogênio/análise , Microbiologia do Solo
13.
Toxicol Appl Pharmacol ; 486: 116943, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38677600

RESUMO

Ulcerative colitis (UC) is an inflammatory condition that affects the colon's lining and increases the risk of colon cancer. Despite ongoing research, there is no identified cure for UC. The recognition of NLRP3 inflammasome activation in the pathogenesis of UC has gained widespread acceptance. Notably, the ketone body ß-hydroxybutyrate inhibits NLRP3 demonstrating its anti-inflammatory properties. Additionally, BD-AcAc 2 is ketone mono ester that increases ß-hydroxybutyrate blood levels. It has the potential to address the constraints associated with exogenous ß-hydroxybutyrate as a therapeutic agent, including issues related to stability and short duration of action. However, the effects of ß-hydroxybutyrate and BD-AcAc 2 on colitis have not been fully investigated. This study found that while both exogenous ß-hydroxybutyrate and BD-AcAc 2 produced the same levels of plasma ß-hydroxybutyrate, BD-AcAc 2 demonstrated superior effectiveness in mitigating dextran sodium sulfate-induced UC in rats. The mechanism of action involves modulating the NF-κB signaling, inhibiting the NLRP3 inflammasome, regulating antioxidant capacity, controlling tight junction protein expression and a potential to inhibit apoptosis and pyroptosis. Certainly, BD-AcAc 2's anti-inflammatory effects require more than just increasing plasma ß-hydroxybutyrate levels and other factors contribute to its efficacy. Local ketone concentrations in the gastrointestinal tract, as well as the combined effect of specific ketone bodies, are likely to have contributed to the stronger protective effect observed with ketone mono ester ingestion in our experiment. As a result, further investigations are necessary to fully understand the mechanisms of BD-AcAc 2 and optimize its use.


Assuntos
Ácido 3-Hidroxibutírico , Colite Ulcerativa , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Ácido 3-Hidroxibutírico/farmacologia , Ratos , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos Sprague-Dawley , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Sulfato de Dextrana/toxicidade , Colo/efeitos dos fármacos , Colo/patologia , Colo/metabolismo , NF-kappa B/metabolismo , Modelos Animais de Doenças , Transdução de Sinais/efeitos dos fármacos , Cetonas/farmacologia
14.
J Magn Reson Imaging ; 59(1): 179-189, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37052580

RESUMO

BACKGROUND: In cardiac T1 mapping, a series of T1 -weighted (T1 w) images are collected and numerically fitted to a two or three-parameter model of the signal recovery to estimate voxel-wise T1 values. To reduce the scan time, one can collect fewer T1 w images, albeit at the cost of precision or/and accuracy. Recently, the feasibility of using a neural network instead of conventional two- or three-parameter fit modeling has been demonstrated. However, prior studies used data from a single vendor and field strength; therefore, the generalizability of the models has not been established. PURPOSE: To develop and evaluate an accelerated cardiac T1 mapping approach based on MyoMapNet, a convolution neural network T1 estimator that can be used across different vendors and field strengths by incorporating the relevant scanner information as additional inputs to the model. STUDY TYPE: Retrospective, multicenter. POPULATION: A total of 1423 patients with known or suspected cardiac disease (808 male, 57 ± 16 years), from three centers, two vendors (Siemens, Philips), and two field strengths (1.5 T, 3 T). The data were randomly split into 60% training, 20% validation, and 20% testing. FIELD STRENGTH/SEQUENCE: A 1.5 T and 3 T, Modified Look-Locker inversion recovery (MOLLI) for native and postcontrast T1 . ASSESSMENT: Scanner-independent MyoMapNet (SI-MyoMapNet) was developed by altering the deep learning (DL) architecture of MyoMapNet to incorporate scanner vendor and field strength as inputs. Epicardial and endocardial contours and blood pool (by manually drawing a large region of interest in the blood pool) of the left ventricle were manually delineated by three readers, with 2, 8, and 9 years of experience, and SI-MyoMapNet myocardial and blood pool T1 values (calculated from four T1 w images) were compared with conventional MOLLI T1 values (calculated from 8 to 11 T1 w images). STATISTICAL TESTS: Equivalency test with 95% confidence interval (CI), linear regression slope, Pearson correlation coefficient (r), Bland-Altman analysis. RESULTS: The proposed SI-MyoMapNet successfully created T1 maps. Native and postcontrast T1 values measured from SI-MyoMapNet were strongly correlated with MOLLI, despite using only four T1 w images, at both field-strengths and vendors (all r > 0.86). For native T1 , SI-MyoMapNet and MOLLI were in good agreement for myocardial and blood T1 values in institution 1 (myocardium: 5 msec, 95% CI [3, 8]; blood: -10 msec, 95%CI [-16, -4]), in institution 2 (myocardium: 6 msec, 95% CI [0, 11]; blood: 0 msec, [-18, 17]), and in institution 3 (myocardium: 7 msec, 95% CI [-8, 22]; blood: 8 msec, [-14, 30]). Similar results were observed for postcontrast T1 . DATA CONCLUSION: Inclusion of field strength and vendor as additional inputs to the DL architecture allows generalizability of MyoMapNet across different vendors or field strength. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 2.


Assuntos
Coração , Miocárdio , Humanos , Masculino , Estudos Retrospectivos , Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Ventrículos do Coração , Reprodutibilidade dos Testes
15.
Curr Atheroscler Rep ; 26(8): 395-410, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38869707

RESUMO

PURPOSE OF REVIEW: To eradicate atherosclerotic diseases, novel biomarkers, and future therapy targets must reveal the burden of early atherosclerosis (AS), which occurs before life-threatening unstable plaques form. The chemical and biological features of microRNAs (miRNAs) make them interesting biomarkers for numerous diseases. We summarized the latest research on miRNA regulatory mechanisms in AS progression studies, which may help us use miRNAs as biomarkers and treatments for difficult-to-treat diseases. RECENT FINDINGS: Recent research has demonstrated that miRNAs have a regulatory function in the observed changes in gene and protein expression during atherogenesis, the process that leads to atherosclerosis. Several miRNAs play a role in the development of atherosclerosis, and these miRNAs could potentially serve as non-invasive biomarkers for atherosclerosis in various regions of the body. These miRNAs have the potential to serve as biomarkers and targets for early treatment of atherosclerosis. The start and development of AS require different miRNAs. It reviews new research on miRNAs affecting endothelium, vascular smooth muscle, vascular inflammation, lipid retention, and cholesterol metabolism in AS. A miRNA gene expression profile circulates with AS everywhere. AS therapies include lipid metabolism, inflammation reduction, and oxidative stress inhibition. Clinical use of miRNAs requires tremendous progress. We think tiny miRNAs can enable personalized treatment.


Assuntos
Aterosclerose , Biomarcadores , MicroRNAs , Humanos , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/diagnóstico , Aterosclerose/terapia , MicroRNAs/genética , MicroRNAs/metabolismo , Biomarcadores/metabolismo , Prognóstico , Animais
16.
Am J Med Genet A ; 194(2): 383-388, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37850521

RESUMO

PLAGL1 is one of a group of imprinted genes, whose altered expression causes imprinting disorders impacting growth, development, metabolism, and behavior. PLAGL1 over-expression causes transient neonatal diabetes mellitus (TNDM type 1) and, based on murine models, under-expression would be expected to cause growth restriction. However, only some reported individuals with upd(6)mat have growth restriction, giving rise to uncertainty about the role of PLAGL1 in human growth. Here we report three individuals investigated for growth restriction, two with upd(6)mat and one with a mosaic deletion of the paternally-inherited allele of PLAGL1. These cases add to evidence of its involvement in pre- and early post-natal human growth.


Assuntos
Impressão Genômica , Dissomia Uniparental , Recém-Nascido , Humanos , Animais , Camundongos , Impressão Genômica/genética , Fatores de Transcrição/genética , Proteínas de Ciclo Celular/genética , Proteínas Supressoras de Tumor/genética
17.
Ann Hematol ; 103(1): 73-88, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37917373

RESUMO

Myeloid malignancies are a group of blood disorders characterized by the proliferation of one or more haematopoietic myeloid cell lineages, predominantly in the bone marrow, and are often caused by aberrant protein tyrosine kinase activity. The protein tyrosine phosphatase CD45 is a trans-membrane molecule expressed on all haemopoietic blood cells except that of platelets and red cells. CD45 regulates various cellular physiological processes including proliferation, apoptosis, and lymphocyte activation. However, its role in chemotherapy response is still unknown; therefore, the aim of this study was to investigate the role of CD45 in myeloid malignancies in terms of cellular growth, apoptosis, and response to chemotherapy. The expression of CD45 on myeloid leukaemia primary cells and cell lines was heterogeneous with HEL and OCI-AML3 cells showing the highest level. Inhibition of CD45 resulted in increased cellular sensitivity to cytarabine and ruxolitinib, the two main therapies for AML and MPN. Bioinformatics analysis identified genes whose expression was correlated with CD45 expression such as JAK2, ACTR2, THAP3 Serglycin, and PBX-1 genes, as well as licensed drugs (alendronate, allopurinol, and balsalazide), which could be repurposed as CD45 inhibitors which effectively increases sensitivity to cytarabine and ruxolitinib at low doses. Therefore, CD45 inhibition could be explored as a potential therapeutic partner for treatment of myeloid malignancies in combination with chemotherapy such as cytarabine especially for elderly patients and those showing chemotherapy resistance.


Assuntos
Leucemia Mieloide Aguda , Leucemia Mieloide , Transtornos Mieloproliferativos , Humanos , Idoso , Leucemia Mieloide/tratamento farmacológico , Pirazóis/uso terapêutico , Nitrilas/uso terapêutico , Citarabina , Transtornos Mieloproliferativos/tratamento farmacológico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo
18.
Mol Cell Biochem ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941031

RESUMO

Bisphenol A (BPA), a common endocrine-disrupting chemical, is found in a wide range of home plastics. Early-life BPA exposure has been linked to neurodevelopmental disorders; however, the link between neuroinflammation, pyroptosis, and the development of psychiatric disorders is rarely studied. The current study attempted to investigate the toxic effect of BPA on inflammatory and microglial activation markers, as well as behavioral responses, in the brains of male rats in a dose- and age-dependent manner. Early BPA exposure began on postnatal day (PND) 18 at dosages of 50 and 125 mg/kg/day. We started with a battery of behavioral activities, including open field, elevated plus- and Y-maze tests, performed on young PND 60 rats and adult PND 95 rats. BPA causes anxiogenic-related behaviors, as well as cognitive and memory deficits. The in vivo and in silico analyses revealed for the first time that BPA is a substantial activator of nuclear factor kappa B (NF-κB), interleukin (IL)-1ß, -2, -12, cyclooxygenase-2, and the NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, with higher beclin-1 and LC3B levels in BPA rats' PFC and hippocampus. Furthermore, BPA increased the co-localization of caspase-1 immunoreactive neurons, as well as unique neurodegenerative histopathological hallmarks. In conclusion, our results support the hypothesis that neuroinflammation and microglial activation are involved with changes in the brain after postnatal BPA exposure and that these alterations may be linked to the development of psychiatric conditions later in life. Collectively, our findings indicate that BPA triggers anxiety-like behaviors and pyroptotic death of nerve cells via the NF-κB/IL-1ß/NLRP3/Caspase-1 pathway.

19.
Med Microbiol Immunol ; 213(1): 3, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448747

RESUMO

Multidrug-resistant clinical isolates of Moraxella catarrhalis have emerged, increasing the demand for the identification of new treatment and prevention strategies. A thorough understanding of how M. catarrhalis can establish an infection and respond to different stressors encountered in the host is crucial for new drug-target identification. Formaldehyde is a highly cytotoxic compound that can be produced endogenously as a by-product of metabolism and exogenously from environmental sources. Pathways responsible for formaldehyde detoxification are thus essential and are found in all domains of life. The current work investigated the role of the system consisting of the S-hydroxymethyl alcohol dehydrogenase (AdhC), a Zn-dependent class III alcohol dehydrogenase, and the S-formyl glutathione hydrolase (FghA) in the formaldehyde detoxification process in M. catarrhalis. Bioinformatics showed that the components of the system are conserved across the species and are highly similar to those of Streptococcus pneumoniae, which share the same biological niche. Isogenic mutants were constructed to study the function of the system in M. catarrhalis. A single fghA knockout mutant did not confer sensitivity to formaldehyde, while the adhC-fghA double mutant is formaldehyde-sensitive. In addition, both mutants were significantly cleared in a murine pulmonary model of infection as compared to the wild type, demonstrating the system's importance for this pathogen's virulence. The respective phenotypes were reversed upon the genetic complementation of the mutants. To date, this is the first study investigating the role of the AdhC-FghA system in formaldehyde detoxification and pathogenesis of M. catarrhalis.


Assuntos
Moraxella catarrhalis , Streptococcus pneumoniae , Animais , Camundongos , Moraxella catarrhalis/genética , Streptococcus pneumoniae/genética , Formaldeído , Glutationa , Hidrolases
20.
Pediatr Res ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38396131

RESUMO

BACKGROUND: Familial Mediterranean fever (FMF) is a chronic inflammatory disease, and it is thought that subclinical inflammation persists even when there are no attacks, eventually causing endothelial dysfunction (ED) and atherosclerosis. Limited data are available about serum endocan, asymmetric dimethylarginine (ADMA) and lipid profile in children with FMF, so we aimed to evaluate these markers in children with FMF during the attack-free period. METHODS: A total of 50 patients diagnosed with FMF and 50 age and sex-matched healthy children were recruited. Serum endocan, ADMA and lipid profiles were measured. Also, atherogenic indices (Castelli's risk indices I and II [CRI I and II], atherogenic index of plasma [AIP] and atherogenic coefficient [AC]) were calculated. RESULTS: Serum endocan, ADMA levels, low-density lipoprotein cholesterol, triglycerides, CRI II and AIP of the FMF patients were significantly higher than controls (p < 0.001). Unlike serum endocan, serum ADMA showed a positive significant correlation with total cholesterol, non-high density lipoprotein cholesterol, CRI I, AIP and AC (p < 0.001, p < 0.001, p = 0.004, p = 0.028, p = 0.004 respectively). CONCLUSION: Serum ADMA and lipid profile might be used as potential markers for endothelial dysfunction and increased cardiovascular risk in FMF patients. IMPACT: Theoretically, serum ADMA may affect lipid profiles and serum endocan represents an intriguing biomarker related to inflammation. Coexistence of dyslipidemia represents an additional risk factor that contributes to the onset of early atherosclerosis. A few studies investigated the role of changes in lipid profile and lipid ratios in accelerated atherosclerosis pathogenesis in FMF patients. The relationship between colchicine and lipid profile is contradictory. Although colchicine can cause dyslipidemia, it also has anti-atherosclerosis effects. Elevated ADMA level and atherogenic indices in FMF children reflect their potential role in the early detection of cardiovascular affection in FMF patients.

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