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1.
Drug Dev Res ; 85(6): e22257, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39245913

RESUMEN

Drug resistance of malignant tumor leads to disease progression be the bottleneck in clinical treatment. Antiangiogenic therapy, which aims to "starve" the tumor by inhibiting angiogenesis, is one of the key strategies in clinical oncology treatments. Recently, dozens of investigational antibody drugs and biosimilars targeting angiogenesis have obtained regulatory approval for the treatment of various malignancies. Moreover, a new generation of bispecific antibodies based on the principle of antiangiogenesis are being advanced for clinical trial to overcome antiangiogenic resistance in tumor treatment or enhance the efficacy of monotherapy. Tumors often develop resistance to antiangiogenesis therapy, presenting as refractory and sometimes even resistant to new therapies, for which there are currently no effective management strategies. Thus, a detailed understanding of the mechanisms mediating resistance to antiangiogenesis antibodies is crucial for improving drug effectiveness and achieving a durable response to antiangiogenic therapy. In this review, we provide a novel perspective on the tumor microenvironment, including antibody structure, tumor stroma, and changes within tumor cells, to analyze the multifactorial reasons underlying resistance to antiangiogenesis antibodies. The review also enumerates biomarkers that indicate resistance and potential strategies for monitoring resistance. Furthermore, based on recent clinical and preclinical studies, we summarize potential strategies and translational clinical trials aimed at overcoming resistance to antiangiogenesis antibodies. This review provides a valuable reference for researchers and clinical practitioners involved in the development of new drugs or therapeutic strategies to overcome antiangiogenesis antibodies resistance.


Asunto(s)
Inhibidores de la Angiogénesis , Resistencia a Antineoplásicos , Neoplasias , Humanos , Inhibidores de la Angiogénesis/uso terapéutico , Inhibidores de la Angiogénesis/farmacología , Neoplasias/tratamiento farmacológico , Microambiente Tumoral/efectos de los fármacos , Biomarcadores de Tumor , Animales , Neovascularización Patológica/tratamiento farmacológico , Anticuerpos Biespecíficos/uso terapéutico , Anticuerpos Biespecíficos/farmacología
2.
Food Chem X ; 23: 101783, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39280229

RESUMEN

Exploring natural antioxidants is essential to delay lipid oxidation. This study investigated the inhibitory effect of Adinandra nitida (AN) extract in six edible oils, compared to TP and TBHQ. Methods included extract preparation, bioactive compounds analysis, in vitro antioxidant activities by FRAP, DPPH, and ABTS assays, fatty acid composition detection, and POV determination. The results showed that AN was rich in total flavonoids, total phenols and had better iron ion reduction ability than TBHQ. In oleic and linoleic acid-rich oils, AN significantly delayed early-stage lipid oxidation, outperforming TP and TBHQ. In linolenic acid-rich oils, AN maintained a stable effect. Molecular docking studies revealed strong binding interactions between main compounds and fatty acids, with Camelliaside A in (7.83) showing higher binding energy to linolenic acid than TBHQ (7.64), supporting the antioxidant effects. These findings suggest AN as a promising natural alternative to synthetic antioxidants, enhancing oil stability and shelf life.

3.
Food Chem ; 463(Pt 2): 141094, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39270496

RESUMEN

The effects of hydrogen sulfide (H2S) on chilling injury (CI), reactive oxygen species (ROS) metabolism, sugar metabolism, pentose phosphate pathway (PPP), and membrane lipid metabolism in loquat fruit throughout the refrigerated period were investigated in this study. The findings indicated that H2S application restrained the increase in internal browning (IB), malondialdehyde (MDA) content, and electrolyte leakage, while sustaining higher total phenolic and total flavonoid levels, and lower soluble quinone content in loquat fruit. Besides, H2S promoted antioxidant accumulation and increased antioxidant enzyme activities by the regulation of ROS metabolism, along with increasing fructose and glucose levels and reducing power by activating sugar metabolism and PPP. Furthermore, H2S treatment retarded the degradation of phospholipids and fatty acids in loquat fruit by modulating membrane lipid metabolism relevant enzyme activities. These findings indicated that H2S application mitigated CI in loquat fruit by alleviating oxidative stress and maintaining cell membrane structural integrity.

4.
Arch Microbiol ; 206(9): 379, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143367

RESUMEN

Multidrug-resistant Klebsiella pneumoniae (MDR-KP) poses a significant challenge in global healthcare, underscoring the urgency for innovative therapeutic approaches. Phage therapy emerges as a promising strategy amidst rising antibiotic resistance, emphasizing the crucial need to identify and characterize effective phage resources for clinical use. In this study, we introduce a novel lytic phage, RCIP0100, distinguished by its classification into the Chaoyangvirus genus and Fjlabviridae family based on International Committee on Taxonomy of Viruses (ICTV) criteria due to low genetic similarity to known phage families. Our findings demonstrate that RCIP0100 exhibits broad lytic activity against 15 out of 27 tested MDR-KP strains, including diverse profiles such as carbapenem-resistant K. pneumoniae (CR-KP). This positions phage RCIP0100 as a promising candidate for phage therapy. Strains resistant to RCIP0100 also showed increased susceptibility to various antibiotics, implying the potential for synergistic use of RCIP0100 and antibiotics as a strategic countermeasure against MDR-KP.


Asunto(s)
Antibacterianos , Bacteriófagos , Farmacorresistencia Bacteriana Múltiple , Klebsiella pneumoniae , Terapia de Fagos , Klebsiella pneumoniae/virología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Bacteriófagos/genética , Bacteriófagos/fisiología , Antibacterianos/farmacología , Infecciones por Klebsiella/microbiología , Genoma Viral , Humanos , Pruebas de Sensibilidad Microbiana
5.
Int J Biol Macromol ; 278(Pt 2): 134873, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39163958

RESUMEN

To solve the problems of flammability and smoldering of cotton fabric, its flame-retardant finishing was executed with biomass wool keratin (WK) and cyclic phosphate ester (CPE) through the soaking and baking process. The synergistic mechanism of WK low-temperature melting and CPE catalytic dehydration prompted the formation of protective carbonization layer on cotton fabric surface, and this protective layer reduced its pyrolysis rate, inhibited the production of combustible materials and improved its flame retardancy. The results of synchronous thermal analysis indicate that the initial decomposition temperature of WK and CPE is lower than that of cotton fabric, and they precede the endothermic degradation before fabric main body. This effectively promotes the low-temperature carbonization of cotton fabric and inhibits its pyrolysis. The initial decomposition temperature of WK/CPE treated fabrics advances by 47.9 °C-97.8 °C, presenting significant low-temperature carbonization trend. Moreover, they form 3.0 %-20.0 % aromatic structural char before the pyrolysis of cotton cellulose due to the low-temperature dehydration and carbonization reactions. The damage length after vertical burning is only 4.0 cm for treated fabric with five layers, its after-flame and smoldering disappear, and its limiting oxygen index value increases to 28.7 %. This research provides an effective idea for the flammability and smoldering problems of cotton fabric.


Asunto(s)
Fibra de Algodón , Retardadores de Llama , Nitrógeno , Nitrógeno/química , Fósforo/química , Pirólisis , Queratinas/química , Temperatura , Textiles , Carbono/química , Frío , Animales
6.
Pediatr Rheumatol Online J ; 22(1): 76, 2024 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-39155376

RESUMEN

OBJECTIVE: This study aimed to develop a novel scoring system utilizing circulating interleukin (IL) levels to predict resistance to intravenous immunoglobulin (IVIG) in Chinese patients with Kawasaki disease (KD). We further compared this scoring system against six previously established scoring methods to evaluate its predictive performance. METHODS: A retrospective analysis was conducted on KD patients who were treated at the cardiovascular medical ward of our institution from January 2020 to December 2022. Six scoring systems (Egami, Formosa, Harada, Kobayashi, Lan and Yang) were analyzed, and a new scoring system was developed based on our data. RESULTS: In our study, 521 KD patients were recruited, 42 of whom (8.06%) were identified as resistant to IVIG. Our study indicated that IVIG-resistant KD patients were at an increased risk for the development of coronary arterial lesions (CALs) (P = 0.001). The evaluation of IVIG resistance using various scoring systems revealed differing levels of sensitivity and specificity, as follows: Egami (38.10% and 88.52%), Formosa (95.24% and 41.13%), Harada (78.57% and 43.22%), Kobayashi (66.67% and 74.95%), Lan (66.67% and 73.49%), and Yang (69.05% and 77.24%). Our novel scoring system utilizing sIL-2R demonstrated the highest sensitivity and specificity of 69.29% and 83.91%, respectively, and calibration curves indicated a favorable predictive accuracy of the model. CONCLUSION: Our newly developed scoring system utilizing sIL-2R demonstrated superior predictive performance in identifying IVIG resistance among Chinese patients with KD.


Asunto(s)
Resistencia a Medicamentos , Inmunoglobulinas Intravenosas , Síndrome Mucocutáneo Linfonodular , Humanos , Síndrome Mucocutáneo Linfonodular/tratamiento farmacológico , Inmunoglobulinas Intravenosas/uso terapéutico , Estudios Retrospectivos , Masculino , Femenino , Preescolar , Lactante , China , Receptores de Interleucina-2/sangre , Niño , Valor Predictivo de las Pruebas , Pueblos del Este de Asia
7.
J Environ Manage ; 367: 122106, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39111006

RESUMEN

Organophosphate esters (OPEs) serve as significant flame retardants and plasticizers in various petrochemical downstream products. The petrochemical industry could be a potential source of atmospheric OPEs, but their emissions from this industry are poorly understood. The present study revealed the spatial variation, emission, and atmospheric transport of traditional and novel OPEs (TOPEs and NOPEs, respectively) in atmospheric particulate matter (PM) across Hainan and Guangdong petrochemical complexes (HNPC and GDPC, respectively) in southern China. The total concentrations of TOPEs ranged from 232 to 46,002 pg/m3 and from 200 to 20,347 pg/m3 in the HNPC and GDPC, respectively, which were substantially higher than those of NOPEs (HNPC: 23.5-147 pg/m3, GDPC: 13.9-465 pg/m3). Enterprises involved in the production of downstream petrochemical products presented relatively high concentrations of OPEs, indicating evident emissions of these pollutants in the petrochemical industry. The correlations of PM-bound OPEs in the atmosphere are determined mainly by their coaddition to industrial products or their coexistence in technical mixtures. The annual emissions of TOPEs and NOPEs in the HNPC were 42.6 kg and 0.34 kg, respectively, and those in the GDPC were 116 kg and 1.85 kg, respectively. OPEs from the HNPC can reach Vietnam, Cambodia, and Guangxi Province, China, and those from the GDPC can reach Guangxi Province and Hunan Province via atmospheric transmission after 24 h of emission. The OPE concentrations reaching the receptor regions were generally less than 3.20 pg/m3. Risk assessment revealed that OPE inhalation exposure on two petrochemical complexes likely poses minor risks for people living in the study areas, but the risk resulting from two chlorinated OPEs should be noted since they are close to the threshold values. This study has implications for enhancing control measures for OPE emissions to reduce health risks related to the petrochemical industry.


Asunto(s)
Monitoreo del Ambiente , Ésteres , Organofosfatos , China , Ésteres/análisis , Medición de Riesgo , Organofosfatos/análisis , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Retardadores de Llama/análisis
8.
Ren Fail ; 46(2): 2387205, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39120130

RESUMEN

BACKGROUND: To compare the impact of tunneled cuffed catheters (TCCs) and arteriovenous fistulas (AVFs) on outcomes in elderly hemodialysis (HD) patients. METHODS: A retrospective matched cohort study was performed. Propensity score matching (PSM) was applied to balance the baseline conditions, and we compared all-cause mortality, major adverse cardiovascular and cerebrovascular events (MACCEs), hospitalization, and infection rates between AVF and TCC patients ≥70 years old. Cox survival analysis was used to analyze the risk factors for death. RESULTS: There were 2119 patients from our center in the Chinese National Renal Data System (CNRDS) between 1 January 2010 and 10 October 2023. Among these patients, 77 TCC patients were matched with 77 AVF patients. There was no significant difference in all-cause mortality between the TCC and AVF groups (30.1/100 vs. 33.3/100 patient-years, p = 0.124). Among the propensity score-matched cohorts, no significant differences in Kaplan-Meier curves were observed between the two groups (log-rank p = 0.242). The TCC group had higher rates of MACCEs, hospitalization, and infection than the AVF group (33.7/100 vs. 29.5/100 patient-years, 101.2/100 vs. 79.5/100 patient-years, and 30.1/100 vs. 14.1/100 patient-years, respectively). Multivariate analysis showed that high Charlson comorbidity index (CCI) score was a risk factor for death. CONCLUSIONS: There was no significant difference in all-cause mortality between elderly HD patients receiving TCCs and AVFs. Compared with those with a TCC, elderly HD patients with an AVF have a lower risk of MACCEs, hospitalization, and infection.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Fallo Renal Crónico , Puntaje de Propensión , Diálisis Renal , Humanos , Masculino , Femenino , Anciano , Estudios Retrospectivos , Fallo Renal Crónico/terapia , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/mortalidad , Factores de Riesgo , Derivación Arteriovenosa Quirúrgica/efectos adversos , Anciano de 80 o más Años , Hospitalización/estadística & datos numéricos , China/epidemiología , Pronóstico , Estimación de Kaplan-Meier
9.
Am J Med Sci ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38992751
10.
Cancer Immunol Immunother ; 73(9): 171, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38954021

RESUMEN

In the intricate landscape of the tumor microenvironment, tumor-associated macrophages (TAMs) emerge as a ubiquitous cellular component that profoundly affects the oncogenic process. The microenvironment of hepatocellular carcinoma (HCC) is characterized by a pronounced infiltration of TAMs, underscoring their pivotal role in modulating the trajectory of the disease. Amidst the evolving therapeutic paradigms for HCC, the strategic reprogramming of metabolic pathways presents a promising avenue for intervention, garnering escalating interest within the scientific community. Previous investigations have predominantly focused on elucidating the mechanisms of metabolic reprogramming in cancer cells without paying sufficient attention to understanding how TAM metabolic reprogramming, particularly lipid metabolism, affects the progression of HCC. In this review article, we intend to elucidate how TAMs exert their regulatory effects via diverse pathways such as E2F1-E2F2-CPT2, LKB1-AMPK, and mTORC1-SREBP, and discuss correlations of TAMs with these processes and the characteristics of relevant pathways in HCC progression by consolidating various studies on TAM lipid uptake, storage, synthesis, and catabolism. It is our hope that our summary could delineate the impact of specific mechanisms underlying TAM lipid metabolic reprogramming on HCC progression and provide useful information for future research on HCC and the development of new treatment strategies.


Asunto(s)
Carcinoma Hepatocelular , Metabolismo de los Lípidos , Neoplasias Hepáticas , Microambiente Tumoral , Macrófagos Asociados a Tumores , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/inmunología , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Macrófagos Asociados a Tumores/metabolismo , Macrófagos Asociados a Tumores/inmunología , Microambiente Tumoral/inmunología , Animales , Reprogramación Celular , Transducción de Señal , Reprogramación Metabólica
11.
Front Med (Lausanne) ; 11: 1356921, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38975054

RESUMEN

Background: Despite previous literature exploring the factors influencing lower urinary tract symptoms (LUTS), few studies have examined the relationship between nutritional status and LUTS. Objectives: The objective of this research was to evaluate the relationship between LUTS and Geriatric Nutritional Risk Index (GNRI) in middle-aged and older men. Methods: We included 2,607 men in the NHANES 2005-2006 and 2007-2008 cycles for cross-sectional analysis. We screened for LUTS based on four specific questions on the relevant questionnaire. We calculated GNRI according to the relevant calculation formula and included other covariates. Multivariate logistic analysis using GNRI as the principal independent variable and adjusting for other covariates were used to determine the association with LUTS, nocturia, and daytime LUTS. Results: According to the responses to the questionnaire, out of 2,607 eligible participants, 471 had LUTS, 906 had nocturia, and 819 had daytime LUTS. In the unadjusted regression model, LUTS (OR = 0.93, 95% CI = 0.91-0.96, p < 0.001), nocturia (OR = 0.90, 95% CI = 0.88-0.93, p < 0.001), and daytime LUTS (OR = 0.96, 95% CI = 0.94-0.99, p = 0.002) were significantly negatively associated with GNRI. After adjustment by adding covariates, LUTS (OR = 0.97,95% CI =0.94-0.99, p = 0.026) and nocturia (OR = 0.94, 95% CI =0.91-0.93, p < 0.001) were significantly negatively associated with GNRI. Conclusion: Low GNRI was associated with the development of LUTS. In the prevention and treatment of LUTS, urologists should consider the impact of nutritional status on LUTS, and interventions for nutritional status may prevent and improve LUTS.

12.
Acta Pharmacol Sin ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39085407

RESUMEN

Tumor immunotherapy characterized by its high specificity and minimal side effects has achieved revolutionary progress in the field of cancer treatment. However, the complex mechanisms of tumor immune microenvironment (TIME) and the individual variability of patients' immune system still present significant challenges to its clinical application. Immunocyte membrane-coated nanocarrier systems, as an innovative biomimetic drug delivery platform, exhibit remarkable advantages in tumor immunotherapy due to their high targeting capability, good biocompatibility and low immunogenicity. In this review we summarize the latest research advances in biomimetic delivery systems based on immune cells for tumor immunotherapy. We outline the existing methods of tumor immunotherapy including immune checkpoint therapy, adoptive cell transfer therapy and cancer vaccines etc. with a focus on the application of various immunocyte membranes in tumor immunotherapy and their prospects and challenges in drug delivery and immune modulation. We look forward to further exploring the application of biomimetic delivery systems based on immunocyte membrane-coated nanoparticles, aiming to provide a new framework for the clinical treatment of tumor immunity.

13.
Biomedicines ; 12(7)2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-39062049

RESUMEN

BACKGROUND: Lung cancer is a common malignant tumor with high morbidity and mortality rate. Glucosamine 6-phosphate N-acetyltransferase (GNPNAT1), which serves as a critical enzyme in hexosamine biosynthetic pathway (HBP), has been identified as a metastasis-associated gene and is upregulated in lung adenocarcinoma (LUAD). However, the exact role and related mechanism of GNPNAT1 in LUAD metastasis remain unknown. METHODS: We analyzed the expression of GNPNAT1 in the public databases and confirmed the results by immunohistochemistry (IHC). The biological functions of GNPNAT1 in LUAD were investigated based on The Cancer Genome Atlas (TCGA). Correlations between GNPNAT1 and cancer immune characteristics were analyzed via the Estimation of Stromal and Immune cells in Malignant Tumor tissues using Expression data (ESTIMATE) and Cell-type Identification by Estimating Relative Subsets of RNA Transcript (CIBERSORT) R package. The underlying mechanisms of altered GNPNAT1 expression on LUAD cell tumorigenesis, proliferation, migration, invasion, and metastasis were explored in vitro and in vivo. RESULTS: We demonstrated that GNPNAT1 expression was significantly increased in LUAD and negatively associated with the overall survival (OS) of patients. hsa-miR-1-3p and hsa-miR-26a-5p were identified as upstream miRNA targets of GNPNAT1. GNPNAT1 was associated with the infiltration levels of CD8 T cells, memory-activated CD4 T cells, NK cells resting, macrophages M0, macrophages M1, neutrophils, gamma delta T cells, and eosinophils, while it was negatively correlated with memory-resting CD4 T cells, regulatory T cells (Tregs), resting NK cells, monocytes, resting dendritic cells, and resting mast cells. GNPNAT1 knockdown significantly inhibited proliferation, migration, invasion, epithelial-mesenchymal transition (EMT) process, and metastasis of LUAD cells, while overexpression of GNPNAT1 revealed the opposite effects. Rescue assay showed that Snai2 knockdown reversed GNPNAT1-induced LUAD cells migration, invasion, and EMT. Mechanistically, GNPNAT1 promoted cancer cell metastasis via repressing ubiquitination degradation of Snai2 in LUAD. CONCLUSIONS: Taken together, these data indicate that GNPNAT1 serves as a prognostic biomarker for LUAD patient. Additionally, GNPNAT1 is critical for promoting tumorigenesis and metastasis of LUAD cells and may be a potential therapeutic target for preventing LUAD metastasis.

14.
Sci Rep ; 14(1): 15849, 2024 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982172

RESUMEN

Dietary antioxidants may have beneficial effects on bone health, but it remains uncertain in children and adolescents. This study investigates the association of composite dietary antioxidant index (CDAI) with bone mineral density (BMD) in children and adolescents aged 8-19 years from the National Health and Nutrition Examination Survey (NHANES) 2007-2010. The study assessed the relationship between CDAI and BMD in 2994 individuals aged 8-19 years (average age 13.48 ± 3.32 years) from the NHANES 2007-2010. Multivariate linear regression analyses were utilized to detect the association between CDAI and total spine, femur neck, and total femur BMD, adjusting for confounders including age, race/ethnicity, sex, poverty income ratio (PIR), body mass index (BMI), serum phosphorus and calcium. Stratified analyses and interaction tests were performed to examine the stability of the results. The weighted characteristics showed that subjects in the fourth CDAI quartile were more likely to be older, men, and Non-Hispanic White. They have higher values of serum total calcium and phosphorus. After adjusting all confounders, CDAI was positively associated with the total spine (ß = 0.0031 95% CI 0.0021-0.0040), total femur (ß = 0.0039 95% CI 0.0028-0.0049), and femur neck BMD (ß = 0.0031 95% CI 0.0021-0.0040) in children and adolescents. Furthermore, we found no interaction effects between different race/ethnicity, age, and sex groups. Our findings suggest that dietary intake of multiple antioxidants was positively associated with BMD in children and adolescents. These findings provide valuable evidence for improving bone health in the early stages of life. However, more prospective studies are required to validate our findings and their causal relationship.


Asunto(s)
Antioxidantes , Densidad Ósea , Encuestas Nutricionales , Humanos , Adolescente , Niño , Femenino , Masculino , Antioxidantes/metabolismo , Adulto Joven , Dieta , Cuello Femoral
15.
Structure ; 32(8): 1222-1230.e4, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-38870940

RESUMEN

The SWI/SNF2 chromatin remodeling factor decreased DNA methylation 1 (DDM1) is essential for the silencing of transposable elements (TEs) in both euchromatic and heterochromatic regions. Here, we determined the cryo-EM structures of DDM1-nucleosomeH2A and DDM1-nucleosomeH2A.W complexes at near-atomic resolution in the presence of the ATP analog ADP-BeFx. The structures show that nucleosomal DNA is unwrapped more on the surface of the histone octamer containing histone H2A than that containing histone H2A.W. DDM1 embraces one DNA gyre of the nucleosome and interacts with the N-terminal tails of histone H4. Although we did not observe DDM1-H2A.W interactions in our structures, the results of the pull-down experiments suggest a direct interaction between DDM1 and the core region of histone H2A.W. Our work provides mechanistic insights into the heterochromatin remodeling process driven by DDM1 in plants.


Asunto(s)
Ensamble y Desensamble de Cromatina , Microscopía por Crioelectrón , Heterocromatina , Histonas , Nucleosomas , Unión Proteica , Nucleosomas/metabolismo , Nucleosomas/química , Heterocromatina/metabolismo , Heterocromatina/química , Histonas/metabolismo , Histonas/química , Histonas/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Modelos Moleculares , Arabidopsis/metabolismo , Arabidopsis/genética , ADN/metabolismo , ADN/química , Factores de Transcripción/metabolismo , Factores de Transcripción/química , Factores de Transcripción/genética , Sitios de Unión
16.
mLife ; 3(1): 101-109, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38827508

RESUMEN

Insertion sequences (ISs) promote the transmission of antimicrobial resistance genes (ARGs) across bacterial populations. However, their contributions and dynamics during the transmission of resistance remain unclear. In this study, we selected IS26 as a representative transposable element to decipher the relationship between ISs and ARGs and to investigate their transfer features and transmission trends. We retrieved 2656  translocatable  IS 26 -bounded  units with  ARGs (tIS26-bUs-ARGs) in complete bacterial genomes from the NCBI RefSeq database. In total, 124 ARGs spanning 12 classes of antibiotics were detected, and the average contribution rate of IS26 to these genes was 41.2%. We found that  IS 26 -bounded  units (IS26-bUs) mediated extensive ARG dissemination within the bacteria of the Gammaproteobacteria class, showing strong transfer potential between strains, species, and even phyla. The IS26-bUs expanded in bacterial populations over time, and their temporal expansion trend was significantly correlated with antibiotic usage. This wide dissemination could be due to the nonspecific target site preference of IS26. Finally, we experimentally confirmed that the introduction of a single copy of IS26 could lead to the formation of a composite transposon mediating the transmission of "passenger" genes. These observations extend our knowledge of the IS26 and provide new insights into the mediating role of ISs in the dissemination of antibiotic resistance.

17.
Adv Sci (Weinh) ; : e2309972, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937990

RESUMEN

Klebsiella pneumoniae, a major clinical pathogen known for causing severe infections, is attracting heightened attention due to its escalating antibiotic resistance. Phages are emerging as a promising alternative to antibiotics; however, their specificity to particular hosts often restricts their use. In this study, a collection of 114 phages is obtained and subjected to analysis against 238 clinical K. pneumoniae strains, revealing a spectrum of lytic behaviors. A correlation between putative tail protein clusters and lysis patterns leads to the discovery of six receptor-binding protein (RBP) clusters that determine host capsule tropism. Significantly, RBPs with cross-capsular lysis capabilities are identified. The newly-identified RBPs provide a toolbox for customizing phages to target diverse capsular types. Building on the toolbox, the engineered phages with altered RBPs successfully shifted and broadened their host capsule tropism, setting the stage for tunable phage that offer a precise and flexible solution to combat K. pneumoniae infections.

18.
Entropy (Basel) ; 26(6)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38920523

RESUMEN

Bridgman once reflected on thermodynamics that the laws of thermodynamics were formulated in their present form by the great founders of thermodynamics, Kelvin and Clausius, before all the essential physical facts were in, and there has been no adequate reexamination of the fundamentals since. Thermodynamics still has unknown possibilities waiting to be explored. This paper begins with a brief review of Clausius's work on the second law of thermodynamics and a reassessment of the content of Clausius's statement. The review tells that what Clausius originally referred to as the second law of thermodynamics was, in fact, the theorem of equivalence of transformations (TET) in a reversible cycle. On this basis, a new symmetric form of Clausius's TET is proposed. This theorem says that the two transformations, i.e., the transformation of heat to work and the transformation of work from high pressure to low pressure, should be equivalent in a reversible work-to-heat cycle. New thermodynamic cyclic laws are developed on the basis of the cycle with two work reservoirs (two pressures), which enriches the fundamental of the second law of thermodynamics.

19.
Bioresour Technol ; 406: 130984, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38880267

RESUMEN

Lignocellulosic biomass, renewable with short growth cycle and diverse sources, can be substituted fossil fuel. However, low effective hydrogen-to-carbon ratio (H/Ceff) limits its applications. Torrefaction and co-pyrolysis with high H/Ceff feedstocks are promising technology. This paper investigated the effect of heating modes on oil-bath torrefaction of walnut shells, followed by fast co-pyrolysis. Six heating modes during oil-bath torrefaction were evaluated. Com1 (Microwave 67 %, Lightwave 33 %) yielded the lowest residual yield 84 wt%, while the highest gas production 495.47 mL/g which mainly composed of CO and CO2. Torrefied feedstock under Com1 had the highest H/Ceff. Decarboxylation and decarbonylation reactions dominated among oil-bath torrefaction. Com1 produced the most hydrocarbons and least oxygen-containing compounds. As microwave ratio decreased, the content of olefins, acids and phenols decreased, monocyclic aromatic hydrocarbons and alcohols was showed opposite tend. This study offers new ideas for microwave and lightwave torrefaction and promoting hydrocarbon production from lignocellulosic biomass.


Asunto(s)
Juglans , Pirólisis , Juglans/química , Biomasa , Aceites de Plantas/química , Calefacción , Biotecnología/métodos , Microondas , Calor , Lignina/química
20.
Sci Total Environ ; 945: 173927, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38901584

RESUMEN

The ubiquity and persistence of organophosphate esters (OPEs) and heavy metal (HMs) pose global environmental risks. This study explored tris(2-chloroisopropyl)phosphate (TCPP) biomineralization coupled to lead (Pb2+) biostabilization driven by denitrifying bacteria (DNB). The domesticated DNB achieved synergistic bioremoval of TCPP and Pb2+ in the batch bioreactor (efficiency: 98 %).TCPP mineralized into PO43- and Cl-, and Pb2+ precipitated with PO43-. The TCPP-degrading/Pb2+-resistant DNB: Achromobacter, Pseudomonas, Citrobacter, and Stenotrophomonas, dominated the bacterial community, and synergized TCPP biomineralization and Pb2+ biostabilization. Metagenomics and metaproteomics revealed TCPP underwent dechlorination, hydrolysis, the TCA cycle-based dissimilation, and assimilation; Pb2+ was detoxified via bioprecipitation, bacterial membrane biosorption, EPS biocomplexation, and efflux out of cells. TCPP, as an initial donor, along with NO3-, as the terminal acceptor, formed a respiratory redox as the primary energy metabolism. Both TCPP and Pb2+ can stimulate phosphatase expression, which established the mutual enhancements between their bioconversions by catalyzing TCPP dephosphorylation and facilitating Pb2+ bioprecipitation. TCPP may alleviate the Pb2+-induced oxidative stress by aiding protein phosphorylation. 80 % of Pb2+ converted into crystalized pyromorphite. These results provide the mechanistic foundations and help develop greener strategies for synergistic bioremediation of OPEs and HMs.


Asunto(s)
Biodegradación Ambiental , Contaminantes Ambientales , Plomo , Organofosfatos , Organofosfatos/química , Organofosfatos/metabolismo , Retardadores de Llama/metabolismo , Contaminantes Ambientales/química , Contaminantes Ambientales/metabolismo , Desnitrificación , Plomo/química , Plomo/metabolismo , Achromobacter/metabolismo , Pseudomonas/metabolismo , Citrobacter/metabolismo , Stenotrophomonas/metabolismo , Metagenómica , Proteómica , Estrés Oxidativo
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