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OBJECTIVE: Breast cancer has become the most prevalent malignant tumor in women, and the occurrence of distant metastasis signifies a poor prognosis. Utilizing predictive models to forecast distant metastasis in breast cancer presents a novel approach. This study aims to utilize readily available clinical data and advanced machine learning algorithms to establish an accurate clinical prediction model. The overall objective is to provide effective decision support for clinicians. METHODS: Data from 239 patients from two centers were analyzed, focusing on clinical blood biomarkers (tumor markers, liver and kidney function, lipid profile, cardiovascular markers). Spearman correlation and the least absolute shrinkage and selection operator regression were employed for feature dimension reduction. A predictive model was built using LightGBM and validated in training, testing, and external validation cohorts. Feature importance correlation analysis was conducted on the clinical model and the comprehensive model, followed by univariate and multivariate regression analysis of these features. RESULTS: Through internal and external validation, we constructed a LightGBM model to predict de novo bone metastasis in newly diagnosed breast cancer patients. The area under the receiver operating characteristic curve values of this model in the training, internal validation test, and external validation test1 cohorts were 0.945, 0.892, and 0.908, respectively. Our validation results indicate that the model exhibits high sensitivity, specificity, and accuracy, making it the most accurate model for predicting bone metastasis in breast cancer patients. Carcinoembryonic Antigen, creatine kinase, albumin-globulin ratio, Apolipoprotein B, and Cancer Antigen 153 (CA153) play crucial roles in the model's predictions. Lipoprotein a, CA153, gamma-glutamyl transferase, α-Hydroxybutyrate dehydrogenase, alkaline phosphatase, and creatine kinase are positively correlated with breast cancer bone metastasis, while white blood cell ratio and total cholesterol are negatively correlated. CONCLUSION: This study successfully utilized clinical blood biomarkers to construct an artificial intelligence model for predicting distant metastasis in breast cancer, demonstrating high accuracy. This suggests potential clinical utility in predicting and identifying distant metastasis in breast cancer. These findings underscore the potential prospect of developing economically efficient and readily accessible predictive tools in clinical oncology.
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Inteligência Artificial , Biomarcadores Tumorais , Neoplasias Ósseas , Neoplasias da Mama , Humanos , Neoplasias da Mama/patologia , Feminino , Neoplasias Ósseas/secundário , Neoplasias Ósseas/sangue , Pessoa de Meia-Idade , Biomarcadores Tumorais/sangue , Adulto , Idoso , Curva ROC , Aprendizado de Máquina , Valor Preditivo dos TestesRESUMO
Monoacylglycerol lipase (MAGL) is the enzyme that is primarily responsible for hydrolyzing the endocannabinoid 2-arachidononylglycerol (2-AG) to arachidonic acid (AA). It has emerged in recent years as a potential drug target for a number of diseases. Herein, we report the discovery of compound 6g from a series of azetidine-piperazine di-amide compounds as a potent, selective, and reversible inhibitor of MAGL. Oral administration of compound 6g increased 2-AG levels in rat brain and produced full efficacy in the rat complete Freund's adjuvant (CFA) model of inflammatory pain.
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Amidas/farmacologia , Azetidinas/farmacologia , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Monoacilglicerol Lipases/antagonistas & inibidores , Piperazinas/farmacologia , Amidas/química , Azetidinas/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estrutura Molecular , Monoacilglicerol Lipases/metabolismo , Piperazinas/química , Relação Estrutura-AtividadeRESUMO
BACKGROUND The tumor microenvironment in lung cancer plays an important role in tumor progression and metastasis. Bone marrow-derived mesenchymal stem cells (MSCs) co-cultured with A549 lung cancer cells show changes in morphology, increase cell proliferation, and cell migration. This study aimed to investigate the effects of Astragalus polysaccharide (APS), a traditional Chinese herbal medicine, on the changes induced in bone marrow-derived MSCs by A549 lung cancer cells in vitro. MATERIAL AND METHODS Bone marrow-derived MSCs were co-cultured with A549 cells (Co-BMSCs). Co-cultured bone marrow-derived MSCs and A549 cells treated with 50 µg/ml of APS (Co-BMSCs + APS) were compared with untreated Co-BMSCs. Cell proliferation was measured using the cell counting kit-8 (CCK-8) assay. Flow cytometry evaluated the cell cycle. Microarray assays for mRNA expression and Western blot for protein expression were used. RESULTS Compared with untreated Co-BMSCs, APS treatment of Co-BMSCs improved cell morphology, reduced cell proliferation, and inhibited cell cycle arrest. The mitogen-activated protein kinase (MAPK)/nuclear factor-kappa B (NF-kappaB) pathway, TP53, caspase-3, acetylated H4K5, acetylated H4K8, and acetylated H3K9 were involved in the regulatory process. CONCLUSIONS APS treatment reduced cell proliferation and morphological changes in bone marrow-derived MSCs that were co-cultured with A549 lung cancer cells in vitro.
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Células A549/efeitos dos fármacos , Astrágalo/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medula Óssea/metabolismo , Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , China , Técnicas de Cocultura , Humanos , Neoplasias Pulmonares/metabolismo , Medicina Tradicional Chinesa/métodos , Células-Tronco Mesenquimais/efeitos dos fármacos , Polissacarídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacosRESUMO
This study aimed to evaluate the therapeutic effect of folic acid (FA) on diabetic retinopathy (DR) in a genetic mouse model of obese type 2 diabetes mellitus (T2D). C57BL/KsJ-db/db (db/db) T2D mice were divided into control, FA, metformin (MET), and FA plus MET groups (n = 10/group). Serum levels of glucose, glycated hemoglobin, and insulin were determined weekly. The retinal thickness was measured using optical coherence tomography (OCT) at 4 weeks after treatments. The retinal expression and serum levels of vascular formation, inflammation, and oxidative stress-associated molecules were examined. Our results demonstrated that FA, but not MET, played a protective role against retinal thinning in the early stage of DR in db/db mice, although FA did not exhibit antihyperglycemic effect. In addition, retinal expression and serum levels of a panel of molecules associated with angiogenesis (CD31 and VEGFR), inflammation (IL-1ß and NLRP3), and oxidative stress (3-NT, 4-HNE, Vav2, and NOX4) were significantly downregulated in FA-treated diabetic mice compared with those in saline-treated controls. Furthermore, the serum level of homocysteine was also markedly decreased following FA treatments. These findings suggest that through potential suppressions on angiogenesis, inflammation, and oxidative stress, FA may serve as a potential therapeutic agent against DR.
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Retinopatia Diabética/tratamento farmacológico , Ácido Fólico , Inflamação/metabolismo , Neovascularização Patológica/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Retina , Análise de Variância , Animais , Biomarcadores/metabolismo , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Modelos Animais de Doenças , Feminino , Ácido Fólico/farmacologia , Ácido Fólico/uso terapêutico , Hemoglobinas Glicadas/análise , Insulina/sangue , Interleucina-1beta/sangue , Camundongos , Camundongos Endogâmicos C57BL , Retina/metabolismo , Retina/patologia , Fator A de Crescimento do Endotélio Vascular/sangueRESUMO
Aberrant activation of matrix metalloproteinases (MMPs) is a common feature of pathological cascades observed in diverse disorders, such as cancer, fibrosis, immune dysregulation, and neurodegenerative diseases. MMP-9, in particular, is highly dynamically regulated in several pathological processes. Development of MMP inhibitors has therefore been an attractive strategy for therapeutic intervention. However, a long history of failed clinical trials has demonstrated that broad-spectrum MMP inhibitors have limited clinical utility, which has spurred the development of inhibitors selective for individual MMPs. Attaining selectivity has been technically challenging because of sequence and structural conservation across the various MMPs. Here, through a biochemical and structural screening paradigm, we have identified JNJ0966, a highly selective compound that inhibited activation of MMP-9 zymogen and subsequent generation of catalytically active enzyme. JNJ0966 had no effect on MMP-1, MMP-2, MMP-3, MMP-9, or MMP-14 catalytic activity and did not inhibit activation of the highly related MMP-2 zymogen. The molecular basis for this activity was characterized as an interaction of JNJ0966 with a structural pocket in proximity to the MMP-9 zymogen cleavage site near Arg-106, which is distinct from the catalytic domain. JNJ0966 was efficacious in reducing disease severity in a mouse experimental autoimmune encephalomyelitis model, demonstrating the viability of this therapeutic approach. This discovery reveals an unprecedented pharmacological approach to MMP inhibition, providing an opportunity to improve selectivity of future clinical drug candidates. Targeting zymogen activation in this manner may also allow for pharmaceutical exploration of other enzymes previously viewed as intractable drug targets.
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Precursores Enzimáticos/antagonistas & inibidores , Precursores Enzimáticos/química , Metaloproteinase 9 da Matriz/química , Inibidores de Metaloproteinases de Matriz/química , Regulação Alostérica , Animais , Células COS , Domínio Catalítico , Chlorocebus aethiops , Precursores Enzimáticos/genética , Precursores Enzimáticos/metabolismo , Humanos , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Domínios ProteicosRESUMO
Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women, resulting in ovulation failure and other metabolic problems. However, the underlying mechanisms of it remain largely uncertain due to the complexity of clinical manifestations. This systemic disorder is involved in endocrine, metabolism, immune system and many organs, and few studies have explored peripheral blood transcriptome in patients with PCOS. We performed gene expression profiling of peripheral blood from 8 PCOS patients and eight healthy women with microarray. The significance analysis of microarray (SAM) software was employed to screen the differentially expressed genes (DEGs) and gene ontology (GO) was used for functional enrichment analysis. In total, 181 DEGs with fold-changes >2.0 and q-values <0.05 were identified between the two groups. Among them, 149 were up-regulated and 32 down-regulated in PCOS. Unsupervised clustering of expressed genes could readily differentiate PCOS from control. More importantly, inflammatory response pathway including 14 dysregulated genes was highly enriched in PCOS. Furthermore, 10 DEGs were validated using quantitative reverse-transcription PCR (qRT-PCR) assays. Our study provides independent evidence for the involvement of systemic inflammatory response in PCOS and it may facilitate a greater understanding of this complex disease.
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Células Sanguíneas/metabolismo , Inflamação/genética , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/genética , Transcriptoma , Adulto , Estudos de Casos e Controles , Análise por Conglomerados , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Inflamação/complicações , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Análise em Microsséries , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/patologiaRESUMO
Objective: This study aims to develop an artificial intelligence model utilizing clinical blood markers, ultrasound data, and breast biopsy pathological information to predict the distant metastasis in breast cancer patients. Methods: Data from two medical centers were utilized, Clinical blood markers, ultrasound data, and breast biopsy pathological information were separately extracted and selected. Feature dimensionality reduction was performed using Spearman correlation and LASSO regression. Predictive models were constructed using LR and LightGBM machine learning algorithms and validated on internal and external validation sets. Feature correlation analysis was conducted for both models. Results: The LR model achieved AUC values of 0.892, 0.816, and 0.817 for the training, internal validation, and external validation cohorts, respectively. The LightGBM model achieved AUC values of 0.971, 0.861, and 0.890 for the same cohorts, respectively. Clinical decision curve analysis showed a superior net benefit of the LightGBM model over the LR model in predicting distant metastasis in breast cancer. Key features identified included creatine kinase isoenzyme (CK-MB) and alpha-hydroxybutyrate dehydrogenase. Conclusion: This study developed an artificial intelligence model using clinical blood markers, ultrasound data, and pathological information to identify distant metastasis in breast cancer patients. The LightGBM model demonstrated superior predictive accuracy and clinical applicability, suggesting it as a promising tool for early diagnosis of distant metastasis in breast cancer.
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Breast cancer metastasis significantly impacts women's health globally. This study aimed to construct predictive models using clinical blood markers and ultrasound data to predict distant metastasis in breast cancer patients, ensuring clinical applicability, cost-effectiveness, relative non-invasiveness, and accessibility of these models. Analysis was conducted on data from 416 patients across two centers, focusing on clinical blood markers (tumor markers, liver and kidney function indicators, blood lipid markers, cardiovascular biomarkers) and maximum lesion diameter from ultrasound. Feature reduction was performed using Spearman correlation and LASSO regression. Two models were built using LightGBM: a clinical model (using clinical blood markers) and a combined model (incorporating clinical blood markers and ultrasound features), validated in training, internal test, and external validation (test1) cohorts. Feature importance analysis was conducted for both models, followed by univariate and multivariate regression analyses of these features. The AUC values of the clinical model in the training, internal test, and external validation (test1) cohorts were 0.950, 0.795, and 0.883, respectively. The combined model showed AUC values of 0.955, 0.835, and 0.918 in the training, internal test, and external validation (test1) cohorts, respectively. Clinical utility curve analysis indicated the combined model's superior net benefit in identifying breast cancer with distant metastasis across all cohorts. This suggests the combined model's superior discriminatory ability and strong generalization performance. Creatine kinase isoenzyme (CK-MB), CEA, CA153, albumin, creatine kinase, and maximum lesion diameter from ultrasound played significant roles in model prediction. CA153, CK-MB, lipoprotein (a), and maximum lesion diameter from ultrasound positively correlated with breast cancer distant metastasis, while indirect bilirubin and magnesium ions showed negative correlations. This study successfully utilized clinical blood markers and ultrasound data to develop AI models for predicting distant metastasis in breast cancer. The combined model, incorporating clinical blood markers and ultrasound features, exhibited higher accuracy, suggesting its potential clinical utility in predicting and identifying breast cancer distant metastasis. These findings highlight the potential prospects of developing cost-effective and accessible predictive tools in clinical oncology.
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Biomarcadores Tumorais , Neoplasias da Mama , Metástase Neoplásica , Humanos , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Feminino , Biomarcadores Tumorais/sangue , Pessoa de Meia-Idade , Adulto , Ultrassonografia/métodos , IdosoRESUMO
Fungi play a crucial role in decomposing litter and facilitating the energy flow between aboveground plants and underground soil in forest ecosystems. However, our understanding how the fungal community involved in litter decomposition responds during forest succession, particularly in disease-driven succession, is still limited. This study investigated the activity of degrading enzyme, fungal community, and predicted function in litter after one year of decomposition in different types of forests during a forest succession gradient from coniferous to deciduous forest, induced by pine wilt disease. The results showed that the weight loss of needles/leaves and twigs did not change along the succession process, but twigs degraded faster than needles/leaves in both pure pine forest and mixed forest. In pure pine forest, peak activities of enzymes involved in carbon degradation (ß-cellobiosidase, ß-glucosidase, ß-D-glucuronidase, ß-xylosidase), nitrogen degradation (N-acetyl-glucosamidase), and organic phosphorus degradation (phosphatase) were observed in needles, which subsequently declined. The fungal diversity and evenness (Shannon's diversity and Shannon's evenness) dropped in twig from coniferous forest to mixed forest during the succession. The dominant phyla in needle/leaf and twig litters were Ascomycota (46.9%) and Basidiomycota (38.9%), with Lambertella pruni and Chalara hughesii identified as the most abundant indicator species. Gymnopus and Desmazierella showed positively correlations with most measured enzyme activities. Functionally, saprotrophs constituted the main trophic mode (47.65%), followed by Pathotroph-Saprotroph-Symbiotroph (30.95%) and Saprotroph-Symbiotroph (10.57%). The fungal community and predicted functional structures in both litter types shifted among different forest types along the succession. These findings indicate that the fungal community in litter decomposition responds differently to disease-induced succession, leading to significant shifts in both the fungal community structure and function.
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Agaricales , Micobioma , Pinus , Ecossistema , Fungos/metabolismo , Florestas , Solo/química , Microbiologia do SoloRESUMO
BACKGROUND: Intestinal mucositis (IM) is characterized by damage to the intestinal mucosa resulting from inhibition of epithelial cell division and loss of renewal capacity following anticancer chemotherapy and radiotherapy. Cytarabine (Ara-C), the main chemotherapy drug for the treatment of leukemia and lymphoma, is a frequent cause of IM. Guiqi Baizhu prescription (GQBZP) is a traditional Chinese medicine with anti-cancer and anti-inflammatory effects. PURPOSE: To determine if GQBZP can ameliorate Ara-C induced IM and identify and characterize the pharmacologic and pharmacodynamic mechanisms. STUDY DESIGN AND METHODS: IM was induced in mice with Ara-C and concurrently treated with orally administered GQBZP. Body weight and food intake was monitored, with HE staining to calculate ileal histomorphometric scoring and villus length/crypt depth. Immunoblotting was used to detect intestinal tissue inflammatory factors. M1 macrophages (M1) were labeled with CD86 by flow cytometry and iNOS + F4/80 by immunofluorescence. Virtual screening was used to find potentially active compounds in GQBZP that targeted JAK2. In vitro, RAW264.7 cells were skewed to M1 macrophage polarization by lipopolysaccharide (LPS) and interferon-γ (INF-γ) and treated orally with GQBZP or potential active compounds. M1 was labeled with CD86 by flow cytometry and iNOS by immunofluorescence. ELISA was used to detect inflammatory factor expression. Active compounds against JAK2, p-JAK2, STAT1 and p-STAT1 were identified by western blotting and HCS fluorescence. Molecular dynamics simulations and pharmacokinetic predictions were carried out on representative active compounds. RESULTS: Experimental results with mice in vivo suggest that GQBZP significantly attenuated Ara-C-induced ileal damage and release of pro-inflammatory factors by inhibiting macrophage polarization to M1. Molecular docking was used to identify potentially active compounds in GQBZP that targeted JAK2, a key factor in macrophage polarization to M1. By examining the main components of each herb and applying Lipinski's rules, ten potentially active compounds were identified. In vitro experimental results suggested that all 10 compounds of GQBZP targeted JAK2 and could inhibit M1 polarization in RAW264.7 cells treated with LPS and INF-γ. Among them, acridine and senkyunolide A down-regulated the expression of JAK2 and STAT1. MD simulations revealed that acridine and senkyunolide A were stable in the active site of JAK2 and exhibited good interactions with the surrounding amino acids. CONCLUSIONS: GQBZP can ameliorate Ara-C-induced IM by reducing macrophage polarization to M1, and acridine and senkyunolide A are representative active compounds in GQBZP that target JAK2 to inhibit M1 polarization. Targeting JAK2 to regulate M1 polarization may be a valuable therapeutic strategy for IM.
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Mucosite , Camundongos , Animais , Mucosite/patologia , Citarabina/farmacologia , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Simulação de Acoplamento Molecular , Macrófagos/metabolismo , Interferon gama/metabolismoRESUMO
The sigma glutathione S-transferases (GSTSs) are a class of cytosolic glutathione S transferases (GSTs) that play important roles in antioxidant defense in insects, but the mechanisms by which GSTSs contribute to antioxidant activity remain unclear. Here, we isolated a GSTS (GSTS6) from Tribolium castaneum and explored its function. Homology and phylogenetic analysis revealed that TcGSTS6 shared high identity with other evolutionarily conserved GSTSs. The recombinant TcGSTS6 protein had strong activity toward cumene hydroperoxide and 4-hydroxynonenal but low activity toward the universal substrate 1-chloro-2,4-dinitrobenzene. Exposure to various types of oxidative stress, including heat, cold, UV and pathogenic microbes, significantly induced TcGSTs6 expression, which indicates that it is involved in antioxidant defense. Knockdown TcGSTs6 by using RNA interference (RNAi) caused reduced antioxidant capacity, which was accomplished by cooperating with other antioxidant genes. Moreover, treatment with various insecticides such as phoxim, lambda-cyhalothrin, dichlorvos and carbofuran revealed that TcGSTS6 plays an important role in insecticide detoxification. The RNAi results showed that TcGSTS6 is essential for embryogenesis in T. castaneum. Our study elucidates the mechanism by which a GSTS contributes to antioxidant activity and enhances our understanding of the functional diversity of GSTSs in insects.
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Inseticidas , Tribolium , Animais , Desenvolvimento Embrionário , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Inativação Metabólica , Filogenia , Tribolium/genética , Tribolium/metabolismoRESUMO
OBJECTIVE: To study the effect and safety of G-CSF combined with Plerixafor on the mobilization of peripheral blood hematopoietic stem cells from healthy related donors of allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: It was analyzed retrospectively that the data of peripheral blood hematopoietic stem cells from 33 (observation group) related donors mobilized by G-CSF plus Plerixafor in Hebei Yanda Lu Daopei Hospital from April 2019 to April 2021. Bone marrow and peripheral blood hematopoietic stem cells (PBSCs) of these donors were respectively collected on the fourth and fifth day of G-CSF-induced mobilization. Following the administration of Plerixafor on the night of the fifth day, PBSCs were collected on the sixth day once again. 46 donors using "G-CSF only" mobilization method in the same period were randomly selected as the control and respectively analyzed the differences of CD34+ cell counts on the fifth and the sixth day in two groups. And the donors' adverse reaction to Plerixafor in the form of questionnaire was also observed. Then it was compared that the patients who underwent allo-HSCT in "G-CSF+Plerixafor" group and "G-CSF only" group in terms of acute GVHD at grade I-IV or III-IV, CMV reactivation and EBV reactivation. RESULTS: CD34+ cells count (M±Q) among PBSCs collected on the fifth and the sixth day in the observation group were (1.71±1.02)×106/kg and (4.23±2.33)×106/kg, respectively. CD34+ cell counts on the sixth day was significantly higher than that of the fifth day (P<0.001); While the counterparts in the control group were (2.47±1.60)×106/kg and (1.87±1.37)×106/kg, respectively. By statistical analysis, CD34+ cell counts on the sixth day was significantly less than that of the fifth day (P<0.001). The adverse reaction to Plerixafor for the donors in the study were all grade 1 or 2 (mild or moderate) according to CTCAE 5.0 and disappeared in a short time. The patients who underwent allo-HSCT in the "G-CSF+Plerixafor" group and "G-CSF only" group were not statistically significant in terms of acute GVHD at grade I-IV or III-IV, CMV reactivation and EBV reactivation (P>0.1). CONCLUSION: The cell mobilization program of G-CSF combined with Plerixafor is safe and effective for being applied to allo-HSCT. The addition of Plerixafor can significantly increase the number of CD34 postive cells in the PBSC collection. Key wordsãã; ;
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Transplante de Células-Tronco Hematopoéticas , Compostos Heterocíclicos , Transplante de Células-Tronco de Sangue Periférico , Antígenos CD34 , Benzilaminas , Ciclamos , Fator Estimulador de Colônias de Granulócitos , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas , Humanos , Estudos RetrospectivosRESUMO
Leaf senescence is the last stage of leaf development and is an orderly biological process accompanied by degradation of macromolecules and nutrient recycling, which contributes to plant fitness. Forward genetic mutant screening and reverse genetic studies of senescence-associated genes (SAGs) have revealed that leaf senescence is a genetically regulated process, and the initiation and progression of leaf senescence are influenced by an array of internal and external factors. Recently, multi-omics techniques have revealed that leaf senescence is subjected to multiple layers of regulation, including chromatin, transcriptional and post-transcriptional, as well as translational and post-translational levels. Although impressive progress has been made in plant senescence research, especially the identification and functional analysis of a large number of SAGs in crop plants, we still have not unraveled the mystery of plant senescence, and there are some urgent scientific questions in this field, such as when plant senescence is initiated and how senescence signals are transmitted. This paper reviews recent advances in the multiple layers of regulation on leaf senescence, especially in post-transcriptional regulation such as alternative splicing.
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Aim: To further enhance the detection sensitivity and increase resolving power of top-down intact protein bioanalysis, middle-down approach was explored. Materials & methods: An monoclonal antibody (mAb) was used as a model protein to evaluate quantitative bioanalytical assay performance and a disulfide linked dimer protein was investigated for its pharmacokinetics properties and catabolism in vivo by middle-down approach. Results & Conclusion: For quantitation of the mAb, different subunits generated by middle-down approach provided different level of signal improvement in biological samples with Lc and half Fc giving five-times better sensitivity than intact mAb. For the dimer protein, middle-down analysis by reduction enabled effective differentiation of the unchanged protein and its oxidized form, and clearly elucidated their respective proteolytic catabolites.
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Anticorpos Monoclonais/análise , Anticorpos Monoclonais/metabolismo , Cromatografia Líquida , Humanos , Espectrometria de MassasRESUMO
The 6-benzhydryl-4-amino-quinolin-2-ones are peripherally restricted CB1 receptor inverse agonists (CB1RIAs) that have been reported to attenuate obesity and improve insulin sensitivity in the diet-induced obese (DIO) mouse model. However, chronic dosing of select compounds from the series showed time-dependent brain accumulation despite a low brain/plasma exposure ratio. To address this issue, a PEGylation approach was employed to identify a novel series of homodimeric 6-benzhydryl-4-amino-quinazoline-PEG conjugates with an extended half-life. The lead compound 18 engaged peripheral CB1Rs in a gastrointestinal (GI) tract motility study and demonstrated a high level of peripheral restriction in a chronic DIO mouse pharmacokinetic study.
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The long circulating half-life and inherently bivalent architecture of IgGs provide an ideal vehicle for presenting otherwise short-lived G-protein-coupled receptor agonists in a format that enables avidity-driven enhancement of potency. Here, we describe the site-specific conjugation of a dual agonist peptide (an oxyntomodulin variant engineered for potency and in vivo stability) to the complementarity-determining regions (CDRs) of an immunologically silent IgG4. A cysteine-containing heavy chain CDR3 variant was identified that provided clean conjugation to a bromoacetylated peptide without interference from any of the endogenous mAb cysteine residues. The resulting mAb-peptide homodimer has high potency at both target receptors (glucagon receptor, GCGR, and glucagon-like peptide 1 receptor, GLP-1R) driven by an increase in receptor avidity provided by the spatially defined presentation of the peptides. Interestingly, the avidity effects are different at the two target receptors. A single dose of the long-acting peptide conjugate robustly inhibited food intake and decreased body weight in insulin resistant diet-induced obese mice, in addition to ameliorating glucose intolerance. Inhibition of food intake and decrease in body weight was also seen in overweight cynomolgus monkeys. The weight loss resulting from dosing with the bivalently conjugated dual agonist was significantly greater than for the monomeric analog, clearly demonstrating translation of the measured in vitro avidity to in vivo pharmacology.
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Anticorpos Monoclonais , Ingestão de Alimentos/efeitos dos fármacos , Obesidade , Oxintomodulina , Peptídeos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/farmacologia , Cisteína/química , Células HEK293 , Humanos , Macaca fascicularis , Masculino , Camundongos , Obesidade/sangue , Obesidade/tratamento farmacológico , Oxintomodulina/química , Oxintomodulina/farmacocinética , Oxintomodulina/farmacologia , Peptídeos/química , Peptídeos/farmacocinética , Peptídeos/farmacologiaRESUMO
The gut hormone PYY3-36 reduces food intake in humans and exhibits at least additive efficacy in combination with GLP-1. However, the utility of PYY analogs as anti-obesity agents has been severely limited by emesis and rapid proteolysis, a profile similarly observed with native PYY3-36 in obese rhesus macaques. Here, we found that antibody conjugation of a cyclized PYY3-36 analog achieved high NPY2R selectivity, unprecedented in vivo stability, and gradual infusion-like exposure. These properties permitted profound reduction of food intake when administered to macaques for 23 days without a single emetic event in any animal. Co-administration with the GLP-1 receptor agonist liraglutide for an additional 5 days further reduced food intake with only one animal experiencing a single bout of emesis. This antibody-conjugated PYY analog therefore may enable the long-sought potential of GLP-1/PYY-based combination treatment to achieve robust, well-tolerated weight reduction in obese patients.
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Anorexia/induzido quimicamente , Peptídeo YY/química , Peptídeo YY/farmacologia , Vômito , Animais , Células CHO , Cricetulus , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Células HEK293 , Humanos , Liraglutida/farmacologia , Macaca mulatta , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Peptídeo YY/administração & dosagem , Vômito/induzido quimicamenteRESUMO
Several classes of arylsulfone-based MMP-2/-9 inhibitors utilizing 6- to 8-membered heterocyclic rings as zinc-binding groups (ZBGs) have been synthesized and their enzyme inhibitory activities were evaluated. Although a number of 6- and 7-membered heterocycles were effective, the most potent arylsulfone inhibitors are based on the rigid 1- or 3-hydroxypyridone ZBG.
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Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/farmacologia , Inibidores de Metaloproteinases de Matriz , Inibidores de Proteases/síntese química , Sulfonas/síntese química , Sulfonas/farmacologia , Zinco/química , Compostos Heterocíclicos/química , Lactamas/síntese química , Lactamas/química , Lactamas/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Piridonas/química , Piridonas/farmacologia , Relação Estrutura-Atividade , Sulfonas/químicaRESUMO
Matrix metalloproteinase-9 (MMP-9) has been implicated in the breakdown of the blood-brain barrier during cerebral ischemia. As a result, inhibition of MMP-9 may have utility as a therapeutic intervention in stroke. Towards this end, we have synthesized a series of 1-hydroxy-2-pyridinones that have excellent in vitro potency in inhibiting MMP-9 in addition to MMP-2. Representative compounds also demonstrate good efficacy in the mouse transient mid-cerebral artery occlusion (tMCAO) model of cerebral ischemia.
Assuntos
Isquemia Encefálica/tratamento farmacológico , Inibidores de Metaloproteinases de Matriz , Inibidores de Proteases/síntese química , Piridonas/síntese química , Piridonas/farmacologia , Administração Oral , Animais , Disponibilidade Biológica , Modelos Animais de Doenças , Concentração Inibidora 50 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Inibidores de Proteases/química , Inibidores de Proteases/farmacocinética , Inibidores de Proteases/farmacologia , Piridonas/química , Piridonas/farmacocinética , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Sulfonamidas/farmacocinética , Sulfonamidas/farmacologia , Zinco/química , Zinco/metabolismoRESUMO
A novel series of 6-benzhydryl-4-amino-quinolin-2-ones was discovered as cannabinoid type 1 receptor (CB1R) inverse agonists based on the high-throughput screening hit, compound 1a. Structure-activity relationships were studied to improve in vitro/in vivo pharmacology and restrict distribution to the peripheral circulation. We adopted several strategies such as increasing topological polar surface area, incorporating discrete polyethylene glycol side chains, and targeting P-glycoprotein (P-gp) to minimize access to the brain. Compound 6a is a P-gp substrate and a potent and highly selective CB1R inverse agonist, demonstrating excellent in vivo metabolic stability and a low brain to plasma ratio. However, brain receptor occupancy studies showed that compound 6a may accumulate in brain with repeat dosing. This was evidenced by compound 6a inhibiting food intake and inducing weight loss in diet-induced obese mice. Thus, a strategy based on P-gp efflux may not be adequate for peripheral restriction of the disclosed quinolinone series.