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1.
Proc Natl Acad Sci U S A ; 121(17): e2402226121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38621137

RESUMO

Since its discovery over three decades ago, signal transducer and activator of transcription 1 (STAT1) has been extensively studied as a central mediator for interferons (IFNs) signaling and antiviral defense. Here, using genetic and biochemical assays, we unveil Thr748 as a conserved IFN-independent phosphorylation switch in Stat1, which restricts IFN signaling and promotes innate inflammatory responses following the recognition of the bacterial-derived toxin lipopolysaccharide (LPS). Genetically engineered mice expressing phospho-deficient threonine748-to-alanine (T748A) mutant Stat1 are resistant to LPS-induced lethality. Of note, T748A mice exhibited undisturbed IFN signaling, as well as total expression of Stat1. Further, the T748A point mutation of Stat1 recapitulates the safeguard effect of the genetic ablation of Stat1 following LPS-induced lethality, indicating that the Thr748 phosphorylation contributes inflammatory functionalities of Stat1. Mechanistically, LPS-induced Toll-like receptor 4 endocytosis activates a cell-intrinsic IκB kinase-mediated Thr748 phosphorylation of Stat1, which promotes macrophage inflammatory response while restricting the IFN and anti-inflammatory responses. Depletion of macrophages restores the sensitivity of the T748A mice to LPS-induced lethality. Together, our study indicates a phosphorylation-dependent modular functionality of Stat1 in innate immune responses: IFN phospho-tyrosine dependent and inflammatory phospho-threonine dependent. Better understanding of the Thr748 phosphorylation of Stat1 may uncover advanced pharmacologically targetable molecules and offer better treatment modalities for sepsis, a disease that claims millions of lives annually.


Assuntos
Lipopolissacarídeos , Transdução de Sinais , Animais , Camundongos , Fosforilação , Lipopolissacarídeos/farmacologia , Interferons/metabolismo , Inflamação/metabolismo , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo
2.
Hum Mol Genet ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710523

RESUMO

Duchenne Muscular Dystrophy (DMD) is a progressive and fatal neuromuscular disease. Cycles of myofibre degeneration and regeneration are hallmarks of the disease where immune cells infiltrate to repair damaged skeletal muscle. Benfotiamine is a lipid soluble precursor to thiamine, shown clinically to reduce inflammation in diabetic related complications. We assessed whether benfotiamine administration could reduce inflammation related dystrophic pathology. Benfotiamine (10 mg/kg/day) was fed to male mdx mice (n = 7) for 15 weeks from 4 weeks of age. Treated mice had an increased growth weight (5-7 weeks) and myofibre size at treatment completion. Markers of dystrophic pathology (area of damaged necrotic tissue, central nuclei) were reduced in benfotiamine mdx quadriceps. Grip strength was increased and improved exercise capacity was found in mdx treated with benfotiamine for 12 weeks, before being placed into individual cages and allowed access to an exercise wheel for 3 weeks. Global gene expression profiling (RNAseq) in the gastrocnemius revealed benfotiamine regulated signalling pathways relevant to dystrophic pathology (Inflammatory Response, Myogenesis) and fibrotic gene markers (Col1a1, Col1a2, Col4a5, Col5a2, Col6a2, Col6a2, Col6a3, Lum) towards wildtype levels. In addition, we observed a reduction in gene expression of inflammatory gene markers in the quadriceps (Emr1, Cd163, Cd4, Cd8, Ifng). Overall, these data suggest that benfotiamine reduces dystrophic pathology by acting on inflammatory and fibrotic gene markers and signalling pathways. Given benfotiamine's excellent safety profile and current clinical use, it could be used in combination with glucocorticoids to treat DMD patients.

3.
Prostate ; 84(5): 460-472, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38192023

RESUMO

BACKGROUND: Through whole-exome sequencing of 60 formalin-fixed paraffin-embedded Nigerian (NGRn) benign prostatic hyperplasia (BPH) samples, we identified germline and somatic alterations in apoptotic pathways impacting BPH development and progression. Prostate enlargement is a common occurrence in male aging; however, this enlargement can lead to lower urinary tract symptoms that negatively impact quality of life. This impact is disproportionately present in men of African ancestry. BPH pathophysiology is poorly understood and studies examining non-European populations are lacking. METHODS: In this study, NGRn BPH, normal prostate, and prostate cancer (PCa) tumor samples were sequenced and compared to characterize genetic alterations in NGRn BPH. RESULTS: Two hundred and two nonbenign, ClinVar-annotated germline variants were present in NGRn BPH samples. Six genes [BRCA1 (92%), HSD3B1 (85%), TP53 (37%), PMS2 (23%), BARD1 (20%), and BRCA2 (17%)] were altered in at least 10% of samples; however, compared to NGRn normal and tumor, the frequency of alterations in BPH samples showed no significant differences at the gene or variant level. BRCA2_rs11571831 and TP53_rs1042522 germline alterations had a statistically significant co-occurrence interaction in BPH samples. In at least two BPH samples, 173 genes harbored somatic variants known to be clinically actionable. Three genes (COL18A1, KIF16B, and LRP1) showed a statistically significant (p < 0.05) higher frequency in BPH. NGRn BPH also had five gene pairs (PKD1/KIAA0100, PKHD1/PKD1, DNAH9/LRP1B, NWD1/DCHS2, and TCERG1/LMTK2) with statistically significant co-occurring interactions. Two hundred and seventy-nine genes contained novel somatic variants in NGRn BPH. Three genes (CABP1, FKBP1C, and RP11-595B24.2) had a statistically significant (p < 0.05) higher alteration frequency in NGRn BPH and three were significantly higher in NGRn tumor (CACNA1A, DMKN, and CACNA2D2). Pairwise Fisher's exact tests showed 14 gene pairs with statistically significant (p < 0.05) interactions and four interactions approaching significance (p < 0.10). Mutational patterns in NGRn BPH were similar to COSMIC (Catalog of Somatic Mutations in Cancer) signatures associated with aging and dysfunctional DNA damage repair. CONCLUSIONS: NGRn BPH contained significant germline alteration interactions (BRCA2_rs11571831 and TP53_rs1042522) and increased somatic alteration frequencies (LMTK2, LRP1, COL18A1, CABP1, and FKBP1C) that impact apoptosis. Normal prostate development is maintained by balancing apoptotic and proliferative activity. Dysfunction in either mechanism can lead to abnormal prostate growth. This work is the first to examine genomic sequencing in NGRn BPH and provides data that fill known gaps in the understanding BPH and how it impacts men of African ancestry.


Assuntos
Hiperplasia Prostática , Neoplasias da Próstata , Humanos , Masculino , Hiperplasia Prostática/genética , Hiperplasia Prostática/patologia , Sequenciamento do Exoma , Qualidade de Vida , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Próstata/patologia , Dineínas do Axonema/genética , Fatores de Elongação da Transcrição/genética , Cinesinas/genética
4.
Appl Environ Microbiol ; : e0086324, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899885

RESUMO

Purple sulfur bacteria (PSB) are capable of anoxygenic photosynthesis via oxidizing reduced sulfur compounds and are considered key drivers of the sulfur cycle in a range of anoxic environments. In this study, we show that Allochromatium vinosum (a PSB species) is capable of autotrophic growth using pyrite as the electron and sulfur source. Comparative growth profile, substrate characterization, and transcriptomic sequencing data provided valuable insight into the molecular mechanisms underlying the bacterial utilization of pyrite and autotrophic growth. Specifically, the pyrite-supported cell cultures ("py"') demonstrated robust but much slower growth rates and distinct patterns from their sodium sulfide-amended positive controls. Up to ~200-fold upregulation of genes encoding various c- and b-type cytochromes was observed in "py," pointing to the high relevance of these molecules in scavenging and relaying electrons from pyrite to cytoplasmic metabolisms. Conversely, extensive downregulation of genes related to LH and RC complex components indicates that the electron source may have direct control over the bacterial cells' photosynthetic activity. In terms of sulfur metabolism, genes encoding periplasmic or membrane-bound proteins (e.g., FccAB and SoxYZ) were largely upregulated, whereas those encoding cytoplasmic proteins (e.g., Dsr and Apr groups) are extensively suppressed. Other notable differentially expressed genes are related to flagella/fimbriae/pilin(+), metal efflux(+), ferrienterochelin(-), and [NiFe] hydrogenases(+). Characterization of the biologically reacted pyrite indicates the presence of polymeric sulfur. These results have, for the first time, put the interplay of PSB and transition metal sulfide chemistry under the spotlight, with the potential to advance multiple fields, including metal and sulfur biogeochemistry, bacterial extracellular electron transfer, and artificial photosynthesis. IMPORTANCE: Microbial utilization of solid-phase substrates constitutes a critical area of focus in environmental microbiology, offering valuable insights into microbial metabolic processes and adaptability. Recent advancements in this field have profoundly deepened our knowledge of microbial physiology pertinent to these scenarios and spurred innovations in biosynthesis and energy production. Furthermore, research into interactions between microbes and solid-phase substrates has directly linked microbial activities to the surrounding mineralogical environments, thereby enhancing our understanding of the relevant biogeochemical cycles. Our study represents a significant step forward in this field by demonstrating, for the first time, the autotrophic growth of purple sulfur bacteria using insoluble pyrite (FeS2) as both the electron and sulfur source. The presented comparative growth profiles, substrate characterizations, and transcriptomic sequencing data shed light on the relationships between electron donor types, photosynthetic reaction center activities, and potential extracellular electron transfer in these organisms capable of anoxygenic photosynthesis. Furthermore, the findings of our study may provide new insights into early-Earth biogeochemical evolutions, offering valuable constraints for understanding the environmental conditions and microbial processes that shaped our planet's history.

5.
J Magn Reson Imaging ; 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38294179

RESUMO

BACKGROUND: Assessment of treatment response in triple-negative breast cancer (TNBC) may guide individualized care for improved patient outcomes. Diffusion tensor imaging (DTI) measures tissue anisotropy and could be useful for characterizing changes in the tumors and adjacent fibroglandular tissue (FGT) of TNBC patients undergoing neoadjuvant systemic treatment (NAST). PURPOSE: To evaluate the potential of DTI parameters for prediction of treatment response in TNBC patients undergoing NAST. STUDY TYPE: Prospective. POPULATION: Eighty-six women (average age: 51 ± 11 years) with biopsy-proven clinical stage I-III TNBC who underwent NAST followed by definitive surgery. 47% of patients (40/86) had pathologic complete response (pCR). FIELD STRENGTH/SEQUENCE: 3.0 T/reduced field of view single-shot echo-planar DTI sequence. ASSESSMENT: Three MRI scans were acquired longitudinally (pre-treatment, after 2 cycles of NAST, and after 4 cycles of NAST). Eleven histogram features were extracted from DTI parameter maps of tumors, a peritumoral region (PTR), and FGT in the ipsilateral breast. DTI parameters included apparent diffusion coefficients and relative diffusion anisotropies. pCR status was determined at surgery. STATISTICAL TESTS: Longitudinal changes of DTI features were tested for discrimination of pCR using Mann-Whitney U test and area under the receiver operating characteristic curve (AUC). A P value <0.05 was considered statistically significant. RESULTS: 47% of patients (40/86) had pCR. DTI parameters assessed after 2 and 4 cycles of NAST were significantly different between pCR and non-pCR patients when compared between tumors, PTRs, and FGTs. The median surface/average anisotropy of the PTR, measured after 2 and 4 cycles of NAST, increased in pCR patients and decreased in non-pCR patients (AUC: 0.78; 0.027 ± 0.043 vs. -0.017 ± 0.042 mm2 /s). DATA CONCLUSION: Quantitative DTI features from breast tumors and the peritumoral tissue may be useful for predicting the response to NAST in TNBC. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 4.

6.
Environ Sci Technol ; 58(21): 9051-9060, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38742946

RESUMO

Research on plant-nanomaterial interactions has greatly advanced over the past decade. One particularly fascinating discovery encompasses the immunomodulatory effects in plants. Due to the low doses needed and the comparatively low toxicity of many nanomaterials, nanoenabled immunomodulation is environmentally and economically promising for agriculture. It may reduce environmental costs associated with excessive use of chemical pesticides and fertilizers, which can lead to soil and water pollution. Furthermore, nanoenabled strategies can enhance plant resilience against various biotic and abiotic stresses, contributing to the sustainability of agricultural ecosystems and the reduction of crop losses due to environmental factors. While nanoparticle immunomodulatory effects are relatively well-known in animals, they are still to be understood in plants. Here, we provide our perspective on the general components of the plant's immune system, including the signaling pathways, networks, and molecules of relevance for plant nanomodulation. We discuss the recent scientific progress in nanoenabled immunomodulation and nanopriming and lay out key avenues to use plant immunomodulation for agriculture. Reactive oxygen species (ROS), the mitogen-activated protein kinase (MAPK) cascade, and the calcium-dependent protein kinase (CDPK or CPK) pathway are of particular interest due to their interconnected function and significance in the response to biotic and abiotic stress. Additionally, we underscore that understanding the plant hormone salicylic acid is vital for nanoenabled applications to induce systemic acquired resistance. It is suggested that a multidisciplinary approach, incorporating environmental impact assessments and focusing on scalability, can expedite the realization of enhanced crop yields through nanotechnology while fostering a healthier environment.


Assuntos
Agricultura , Nanoestruturas , Imunidade Vegetal
7.
Environ Sci Technol ; 58(2): 1211-1222, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38173352

RESUMO

Molybdenum disulfide (nano-MoS2) nanomaterials have shown great potential for biomedical and catalytic applications due to their unique enzyme-mimicking properties. However, their potential agricultural applications have been largely unexplored. A key factor prior to the application of nano-MoS2 in agriculture is understanding its behavior in a complex soil-plant system, particularly in terms of its transformation. Here, we investigate the distribution and transformation of two types of nano-MoS2 (MoS2 nanoparticles and MoS2 nanosheets) in a soil-soybean system through a combination of synchrotron radiation-based X-ray absorption near-edge spectroscopy (XANES) and single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS). We found that MoS2 nanoparticles (NPs) transform dynamically in soil and plant tissues, releasing molybdenum (Mo) and sulfur (S) that can be incorporated gradually into the key enzymes involved in nitrogen metabolism and the antioxidant system, while the rest remain intact and act as nanozymes. Notably, there is 247.9 mg/kg of organic Mo in the nodule, while there is only 49.9 mg/kg of MoS2 NPs. This study demonstrates that it is the transformation that leads to the multifunctionality of MoS2, which can improve the biological nitrogen fixation (BNF) and growth. Therefore, MoS2 NPs enable a 30% increase in yield compared to the traditional molybdenum fertilizer (Na2MoO4). Excessive transformation of MoS2 nanosheets (NS) leads to the overaccumulation of Mo and sulfate in the plant, which damages the nodule function and yield. The study highlights the importance of understanding the transformation of nanomaterials for agricultural applications in future studies.


Assuntos
Nanoestruturas , Solo , Solo/química , Glycine max , Molibdênio , Agricultura
8.
J Pediatr Hematol Oncol ; 46(2): e184-e187, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38099690

RESUMO

Anaplastic lymphoma kinase ( ALK )-fusion sarcomas are rare part of the emerging theoretically targetable tyrosine kinase RAS::MAPK pathway fusion myopericytic-ovoid sarcomas. We report our clinicopathologic and treatment experience with an ALK fusion sarcoma. A novel ELKS/RAB6-interacting/CAST family member 1 - unaligned ALK fusion infiltrative nonmetastatic low-grade sarcoma of the right hand of a 15-month-old male was treated with crizotinib, an ALK tyrosine kinase inhibitor as oral monotherapy, inducing complete radiographic and clinical resolution by 10 months and sustained response now over 12 months after elective discontinuation. Crizotinib can successfully be used to treat unresectable novel ALK fusion sarcomas.


Assuntos
Neoplasias Pulmonares , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Masculino , Criança , Lactente , Crizotinibe/uso terapêutico , Quinase do Linfoma Anaplásico/genética , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Sarcoma/tratamento farmacológico , Sarcoma/genética , Proteínas Tirosina Quinases/uso terapêutico , Neoplasias de Tecidos Moles/tratamento farmacológico , Neoplasias Pulmonares/patologia
9.
Plant Cell Rep ; 43(3): 64, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38340214

RESUMO

KEY MESSAGE: This study demonstrates the crucial role of OsPIP2;6 for translocation of arsenic from roots to shoots, which can decrease arsenic accumulation in rice for improved food safety. Arsenic (As) contamination in food and water, primarily through rice consumption, poses a significant health risk due to its natural tendency to accumulate inorganic arsenic (iAs). Understanding As transport mechanisms is vital for producing As-free rice. This study investigates the role of rice plasma membrane intrinsic protein, OsPIP2;6, for AsIII tolerance and accumulation. RNAi-mediated suppression of OsPIP2;6 expression resulted in a substantial (35-65%) reduction in As accumulation in rice shoots, while root arsenic levels remained largely unaffected. Conversely, OsPIP2;6 overexpression led to 15-76% higher arsenic accumulation in shoots, with no significant change in root As content. In mature plants, RNAi suppression caused (19-26%) decrease in shoot As, with flag leaves and grains showing a 16% reduction. OsPIP2;6 expression was detected in both roots and shoots, with higher transcript levels in shoots. Localization studies revealed its presence in vascular tissues of both roots and shoots. Overall, our findings highlight OsPIP2;6's role in root-to-shoot As translocation, attributed to its specific localization in the vascular tissue of roots and leaves. This knowledge can facilitate the development of breeding programs to mitigate As accumulation in rice and other food crops for improved food safety and increasing productivity on As-contaminated soils.


Assuntos
Arsênio , Oryza , Radioisótopos , Oryza/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Melhoramento Vegetal , Proteínas de Membrana/metabolismo , Membrana Celular/metabolismo
10.
Int J Mol Sci ; 25(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38791299

RESUMO

Type 1 diabetes (T1D) affects gastrointestinal (GI) motility, favoring gastroparesis, constipation, and fecal incontinence, which are more prevalent in women. The mechanisms are unknown. Given the G-protein-coupled estrogen receptor's (GPER) role in GI motility, we investigated sex-related diabetes-induced epigenetic changes in GPER. We assessed GPER mRNA and protein expression levels using qPCR and Western blot analyses, and quantified the changes in nuclear DNA methyltransferases and histone modifications (H3K4me3, H3Ac, and H3K27Ac) by ELISA kits. Targeted bisulfite and chromatin immunoprecipitation assays were used to evaluate DNA methylation and histone modifications around the GPER promoter by chromatin immunoprecipitation assays in gastric and colonic smooth muscle tissues of male and female control (CTR) and non-obese diabetic (NOD) mice. GPER expression was downregulated in NOD, with sex-dependent variations. In the gastric smooth muscle, not in colonic smooth muscle, downregulation coincided with differences in methylation ratios between regions 1 and 2 of the GPER promoter of NOD. DNA methylation was higher in NOD male colonic smooth muscle than in NOD females. H3K4me3 and H3ac enrichment decreased in NOD gastric smooth muscle. H3K4me3 levels diminished in the colonic smooth muscle of NOD. H3K27ac levels were unaffected, but enrichment decreased in NOD male gastric smooth muscle; however, it increased in the NOD male colonic smooth muscle and decreased in the female NOD colonic smooth muscle. Male NOD colonic smooth muscle exhibited decreased H3K27ac levels, not female, whereas female NOD colonic smooth muscle demonstrated diminished enrichment of H3ac at the GPER promoter, contrary to male NOD. Sex-specific epigenetic mechanisms contribute to T1D-mediated suppression of GPER expression in the GI tract. These insights advance our understanding of T1D complications and suggest promising avenues for targeted therapeutic interventions.


Assuntos
Colo , Metilação de DNA , Epigênese Genética , Histonas , Camundongos Endogâmicos NOD , Músculo Liso , Regiões Promotoras Genéticas , Receptores Acoplados a Proteínas G , Animais , Feminino , Masculino , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Músculo Liso/metabolismo , Camundongos , Histonas/metabolismo , Colo/metabolismo , Colo/patologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/genética , Receptores de Estrogênio/metabolismo , Receptores de Estrogênio/genética , Estômago/patologia
11.
J Environ Manage ; 362: 121316, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838540

RESUMO

Given the increasing concern over Cd contamination of agricultural soils in China, reducing the availability of the toxic metal has become an important remedial strategy. However, the lack of a unified evaluation framework complicates the assessment of remediation efficiency of different practices. Here, we evaluated the general extraction method (GEM) of available Cd in nine typical soil types by comparing extraction agents, including CaCl2, EDTA, Mehlich-Ⅲ, HCl and DTPA. The safe grain concentration of different agricultural products from National Food Safety Standards Limits of Contaminants in Food (GB 2762-2022) was then applied to understand soil limited available Cd concentration based on dose-response curves. We also derived environmental risk threshold (HC5) values for Cd remediation in agricultural soils by constructing species sensitivity distribution (SSD) curves. The results showed that Mehlich-Ⅲ best predicted Cd accumulation in crops (with 76.5% of explanation of grain Cd) and was selected as the GEM of soil available Cd for subsequent analyses. The regression coefficient (R2) of dose-response curves fitting between Cd absorption in crop tissues and soil available Cd extracted by GEM based on 30 different crop species varied from 51.0% to 79.5%, and the derived limit concentration of soil available Cd based on standard GB 2762-2022 was 0.18-0.76 mg‧kg-1. An HC5 of 0.19 mg‧kg-1 was then calculated, meaning that a concentration of available Cd in agricultural soil below 0.19 mg‧kg-1 ensures that 95% of agricultural products meet the quality and safety requirements of standard GB 2762-2022. The prediction model was well verified in the field test, indicating that can correctly estimate the soil available Cd based on the content of Cd in plant. This study provides a robust scientific framework for deriving the risk threshold for Cd remediation in agricultural soils and could be quite useful for establishing soil remediation standards.


Assuntos
Agricultura , Cádmio , Recuperação e Remediação Ambiental , Poluentes do Solo , Solo , Cádmio/análise , Poluentes do Solo/análise , China , Solo/química , Recuperação e Remediação Ambiental/métodos , Produtos Agrícolas , População do Leste Asiático
12.
Semin Cancer Biol ; 82: 26-34, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34147641

RESUMO

Triple-negative breast cancer (TNBC) is a broad collection of breast cancer that tests negative for estrogen receptors (ER), progesterone receptors (PR), and excess human epidermal growth factor receptor 2 (HER2) protein. TNBC is considered to have poorer prognosis than other types of breast cancer because of a lack of effective therapeutic targets. The success of precision cancer therapies relies on the clarification of key molecular mechanisms that drive tumor growth and metastasis; however, TNBC is highly heterogeneous in terms of their cellular lineage composition and the molecular nature within each individual case. In particular, the rare and sometimes slow cycling cancer stem cells (CSCs) can provide effective means for TNBC to resist various treatments. Single cell analysis technologies, including single-cell RNA-seq (scRNA-seq) and proteomics, provide an avenue to unravel patient-level intratumoral heterogeneity by identifying CSCs populations, CSC biomarkers and the range of tumor microenvironment cellular constituents that contribute to tumor growth. This review discusses the emerging evidence for the role of CSCs in driving TNBC incidence and the therapeutic implications in manipulating molecular signaling against this rare cell population for the control of this deadly disease.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Células-Tronco Neoplásicas/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/terapia , Microambiente Tumoral
13.
Plant Cell Physiol ; 63(12): 1840-1847, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36255098

RESUMO

The global increase in nanotechnology applications has been unprecedented and has now moved into the area of agriculture and food production. Applications with promising potential in sustainable agriculture include nanobiosensors, nanofertilizers, nanopesticides, nano-mediated remediation strategies for contaminated soils and nanoscale strategies to increase crop production and protection. Given this, the impact of nanomaterials/nanoparticles (NPs) on plant species needs to be thoroughly evaluated as this represents a critical interface between the biosphere and the environment. Importantly, phytohormones represent a critical class of biomolecules to plant health and productivity; however, the impact of NPs on these molecules is poorly understood. In addition, phytohormones, and associated pathways, are widely explored in agriculture to influence several biological processes for the improvement of plant growth and productivity under natural as well as stressed conditions. However, the impact of exogenous applications of phytohormones on NP-treated plants has not been explored. The importance of hormone signaling and cross-talk with other metabolic systems makes these biomolecules ideal candidates for a thorough assessment of NP impacts on plant species. This article presents a critical evaluation of the existing yet limited literature available on NP-phytohormone interactions in plants. In addition, the developing strategy of nano-enabled precision delivery of phytohormones via nanocarriers will be explored. Finally, directions for future research and critical knowledge gaps will be identified for this important aspect of nano-enabled agriculture.


Assuntos
Fenômenos Biológicos , Nanoestruturas , Reguladores de Crescimento de Plantas , Desenvolvimento Vegetal , Plantas , Hormônio do Crescimento
14.
J Clin Immunol ; 44(1): 27, 2023 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-38129328

RESUMO

Zeta-chain associated protein kinase 70 kDa (ZAP70) combined immunodeficiency (CID) is an autosomal recessive severe immunodeficiency that is characterized by abnormal T-cell receptor signaling. Children with the disorder typically present during the first year of life with diarrhea, failure to thrive, and recurrent bacterial, viral, or opportunistic infections. To date, the only potential cure is hematopoietic stem cell transplant (HSCT). The majority of described mutations causing disease occur in the homozygous state, though heterozygotes are reported without a clear understanding as to how the individual mutations interact to cause disease. This case describes an infant with novel ZAP-70 deficiency mutations involving the SH2 and kinase domains cured with allogeneic HSCT utilizing a reduced-intensity conditioning regimen and graft manipulation. We then were able to further elucidate the molecular signaling alterations imparted by these mutations that lead to altered immune function. In order to examine the effect of these novel compound ZAP70 heterozygous mutations on T cells, Jurkat CD4+ T cells were transfected with either wild type, or with individual ZAP70 R37G and A507T mutant constructs. Downstream TCR signaling events and protein localization results link these novel mutations to the expected immunological outcome as seen in the patient's primary cells. This study further characterizes mutations in the ZAP70 gene as combined immunodeficiency and the clinical phenotype.


Assuntos
Síndromes de Imunodeficiência , Imunodeficiência Combinada Severa , Criança , Humanos , Lactente , Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/terapia , Mutação , Imunodeficiência Combinada Severa/diagnóstico , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/terapia , Transdução de Sinais , Linfócitos T/metabolismo , Proteína-Tirosina Quinase ZAP-70/genética
15.
Breast Cancer Res Treat ; 199(3): 457-469, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37061619

RESUMO

PURPOSE: Neoadjuvant anti-PD-(L)1 therapy improves the pathological complete response (pCR) rate in unselected triple-negative breast cancer (TNBC). Given the potential for long-term morbidity from immune-related adverse events (irAEs), optimizing the risk-benefit ratio for these agents in the curative neoadjuvant setting is important. Suboptimal clinical response to initial neoadjuvant therapy (NAT) is associated with low rates of pCR (2-5%) and may define a patient selection strategy for neoadjuvant immune checkpoint blockade. We conducted a single-arm phase II study of atezolizumab and nab-paclitaxel as the second phase of NAT in patients with doxorubicin and cyclophosphamide (AC)-resistant TNBC (NCT02530489). METHODS: Patients with stage I-III, AC-resistant TNBC, defined as disease progression or a < 80% reduction in tumor volume after 4 cycles of AC, were eligible. Patients received atezolizumab (1200 mg IV, Q3weeks × 4) and nab-paclitaxel (100 mg/m2 IV,Q1 week × 12) as the second phase of NAT before undergoing surgery followed by adjuvant atezolizumab (1200 mg IV, Q3 weeks, × 4). A two-stage Gehan-type design was employed to detect an improvement in pCR/residual cancer burden class I (RCB-I) rate from 5 to 20%. RESULTS: From 2/15/2016 through 1/29/2021, 37 patients with AC-resistant TNBC were enrolled. The pCR/RCB-I rate was 46%. No new safety signals were observed. Seven patients (19%) discontinued atezolizumab due to irAEs. CONCLUSION: This study met its primary endpoint, demonstrating a promising signal of activity in this high-risk population (pCR/RCB-I = 46% vs 5% in historical controls), suggesting that a response-adapted approach to the utilization of neoadjuvant immunotherapy should be considered for further evaluation in a randomized clinical trial.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Antraciclinas/uso terapêutico , Neoplasias de Mama Triplo Negativas/patologia , Terapia Neoadjuvante , Neoplasias da Mama/tratamento farmacológico , Paclitaxel/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
16.
Small ; 19(15): e2207136, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36599658

RESUMO

The nano-enabled crop protecting agents have been emerging as a cost-effective, eco-friendly, and sustainable alternative to conventional chemical pesticides. Here, the antibacterial activity and disease-suppressive potential of biogenic copper nanoparticles (bio-CuNPs) against bacterial fruit blotch (BFB), caused by Acidovorax citrulli (Ac), in watermelon (Citrullus lanatus L.) is discussed. CuNPs are extracellularly biosynthesized using a locally isolated bacterial strain Bacillus altitudinis WM-2/2, and have spherical shapes of 29.11-78.56 nm. Various metabolites, such as alcoholic compounds, carboxylic acids, alkenes, aromatic amines, and halo compounds, stabilize bio-CuNPs. Foliar application of bio-CuNPs increases the Cu accumulation in shoots/roots (66%/27%), and promotes the growth performance of watermelon plants by improving fresh/dry weight (36%/39%), through triggering various imperative physiological and biochemical processes. Importantly, bio-CuNPs at 100 µg mL-1 significantly suppress watermelon BFB through balancing reactive oxygen species system, improving photosynthesis capacity, and modulating stomatal immunity. Bio-CuNPs show obvious antibacterial activity against Ac by inducing oxidative stress, biofilm inhibition, and cellular integrity disruption. These findings demonstrate that bio-CuNPs can suppress watermelon BFB through direct antibacterial activity and induction of active immune response in watermelon plants, and highlight the value of this approach as a powerful tool to increase agricultural production and alleviate food insecurity.


Assuntos
Citrullus , Citrullus/microbiologia , Frutas/microbiologia , Cobre , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Antibacterianos/farmacologia
17.
Small ; 19(2): e2205687, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36382544

RESUMO

The use of nanofabricated materials is being explored for the potential in crop disease management. Chemically synthesized micronutrient nanoparticles (NPs) have been shown to reduce crop diseases; however, the potential of biogenic manganese NPs (bio-MnNPs) in disease control is unknown. Here, the potential and mechanism of bio-MnNPs in suppression of watermelon Fusarium wilt, caused by Fusarium oxysporum f. sp. niveum (Fon) are reported. Bio-MnNPs are synthesized by cell-free cultural filtrate of a waterrmelon rhizosphere bacterial strain Bacillus megaterium NOM14, and are found spherical in shape with a size range of 27.0-65.7 nm. Application of bio-MnNPs at 100 µg mL-1 increases Mn content in watermelon roots/shoots and improves growth performance through enhancing multiple physiological processes, including antioxidative capacity. Bio-MnNPs at 100 µg mL-1 suppress Fusarium wilt through inhibiting colonization and invasive growth of Fon in watermelon roots/stems, and inhibit Fon vegetative growth, conidiation, conidial morphology, and cellular integrity. Bio-MnNPs potentiate watermelon systemic acquired resistance by triggering the salicylic acid signaling upon Fon infection, and reshape the soil microbial community by improving fungal diversity. These findings demonstrate that bio-MnNPs suppress watermelon Fusarium wilt by multiple ex planta and in planta mechanisms, and offer a promising nano-enabled strategy for the sustainable management of crop diseases.


Assuntos
Citrullus , Fusarium , Citrullus/microbiologia , Solo , Fusarium/fisiologia , Manganês , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
18.
Exp Brain Res ; 241(2): 365-382, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36534141

RESUMO

Neuromodulation via spinal stimulation has been investigated for improving motor function and reducing spasticity after spinal cord injury (SCI) in humans. Despite the reported heterogeneity of outcomes, few investigations have attempted to discern commonalities among individual responses to neuromodulation, especially the impact of stimulation frequencies. Here, we examined how exposure to continuous lumbosacral transcutaneous spinal stimulation (TSS) across a range of frequencies affects robotic torques and EMG patterns during stepping in a robotic gait orthosis on a motorized treadmill. We studied nine chronic motor-incomplete SCI individuals (8/1 AIS-C/D, 8 men) during robot-guided stepping with body-weight support without and with TSS applied at random frequencies between 1 and up to 100 Hz at a constant, individually selected stimulation intensity below the common motor threshold for posterior root reflexes. The hip and knee robotic torques needed to maintain the predefined stepping trajectory and EMG in eight bilateral leg muscles were recorded. We calculated the standardized mean difference between the stimulation conditions grouped into frequency bins and the no stimulation condition to determine changes in the normalized torques and the average EMG envelopes. We found heterogeneous changes in robotic torques across individuals. Agglomerative clustering of robotic torques identified four groups wherein the patterns of changes differed in magnitude and direction depending mainly on the stimulation frequency and stance/swing phase. On one end of the spectrum, the changes in robotic torques were greater with increasing stimulation frequencies (four participants), which coincided with a decrease in EMG, mainly due to the reduction of clonogenic motor output in the lower leg muscles. On the other end, we found an inverted u-shape change in torque over the mid-frequency range along with an increase in EMG, reflecting the augmentation of gait-related physiological (two participants) or pathophysiological (one participant) output. We conclude that TSS during robot-guided stepping reveals different frequency-dependent motor profiles among individuals with chronic motor incomplete SCI. This suggests the need for a better understanding and characterization of motor control profiles in SCI when applying TSS as a therapeutic intervention for improving gait.


Assuntos
Robótica , Traumatismos da Medula Espinal , Estimulação da Medula Espinal , Masculino , Humanos , Caminhada/fisiologia , Eletromiografia , Músculo Esquelético/fisiologia , Medula Espinal/fisiologia
19.
Environ Sci Technol ; 57(26): 9773-9781, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37334664

RESUMO

Orthogonal techniques were used to track manganese nanoparticles (MnNPs) in Capsicum annuum L. leaf tissue and cell compartments and subsequently to explain the mechanism of uptake, translocation, and cellular interaction. C. annuum L was cultivated and foliarly exposed to MnNPs (100 mg/L, 50 mL/per leaf) before analysis by using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) as well as dark-field hyperspectral and two-photon microscopy. We visualized the internalization of MnNP aggregates from the leaf surface and observed particle accumulation in the leaf cuticle and epidermis as well as spongy mesophyll and guard cells. These techniques enabled a description of how MnNPs cross different plant tissues as well as selectively accumulate and translocate in specific cells. We also imaged abundant fluorescent vesicles and vacuoles containing MnNPs, indicating likely induction of autophagy processes in C. annuum L., which is the bio-response upon storing or transforming the particles. These findings highlight the importance of utilizing orthogonal techniques to characterize nanoscale material fate and distribution with complex biological matrices and demonstrate that such an approach offers a significant mechanistic understanding that can inform both risk assessment and efforts aimed at applying nanotechnology to agriculture.


Assuntos
Capsicum , Nanopartículas , Capsicum/química , Manganês , Microscopia Eletrônica de Varredura , Autofagia
20.
Environ Sci Technol ; 57(48): 19932-19941, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37975618

RESUMO

Climate change-induced extreme weather events (heat, cold, drought, and flooding) will severely affect crop production. Increasing the resilience of crops to fluctuating environmental conditions is critically important. Here, we report that nanomaterials (NMs) with reactive oxygen species (ROS)-generating properties can be used as seed priming agents to simultaneously enhance the tolerance of maize seeds and seedlings to diverse and even multiple stresses. Maize seeds primed with 40 mg/L silver nanoparticles (AgNPs) exhibited accelerated seed germination and an increased germination rate, greater seedling vigor, and better seedling growth under drought (10% and 20% PEG), saline (50 and 100 mM NaCl), and cold (15 °C) stress conditions, indicating enhanced resilience to diverse stresses. Importantly, maize resistance to simultaneous multiple stresses (drought and cold, drought and salt, and salt and cold) was markedly enhanced. Under drought conditions, seed priming significantly boosted root hair density and length (17.3-82.7%), which enabled greater tolerance to water deficiency. RNA-seq analysis reveals that AgNPs seed priming induced a transcriptomic shift in maize seeds. Plant hormone signal transduction and MAPK signaling pathways were activated upon seed priming. Importantly, low-cost and environmentally friendly ROS-generating Fe-based NMs (Fe2O3 and Fe3O4 NPs) were also demonstrated to enhance the resistance of seeds and seedlings to drought, salt, and cold stresses. These findings demonstrate that a simple seed priming strategy can be used to significantly enhance the climate resilience of crops through modulated ROS homeostasis and that this approach could be a powerful nanoenabled tool for addressing worsening food insecurity.


Assuntos
Nanopartículas Metálicas , Zea mays , Espécies Reativas de Oxigênio/metabolismo , Zea mays/metabolismo , Nanopartículas Metálicas/toxicidade , Prata , Plântula/metabolismo , Germinação , Estresse Fisiológico , Cloreto de Sódio/farmacologia , Sementes/metabolismo
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