Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 457
Filtrar
Más filtros

País/Región como asunto
Intervalo de año de publicación
1.
Nature ; 613(7942): 145-152, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36517600

RESUMEN

Phytohormone signalling pathways have an important role in defence against pathogens mediated by cell-surface pattern recognition receptors and intracellular nucleotide-binding leucine-rich repeat class immune receptors1,2 (NLR). Pathogens have evolved counter-defence strategies to manipulate phytohormone signalling pathways to dampen immunity and promote virulence3. However, little is known about the surveillance of pathogen interference of phytohormone signalling by the plant innate immune system. The pepper (Capsicum chinense) NLR Tsw, which recognizes the effector nonstructural protein NSs encoded by tomato spotted wilt orthotospovirus (TSWV), contains an unusually large leucine-rich repeat (LRR) domain. Structural modelling predicts similarity between the LRR domain of Tsw and those of the jasmonic acid receptor COI1, the auxin receptor TIR1 and the strigolactone receptor partner MAX2. This suggested that NSs could directly target hormone receptor signalling to promote infection, and that Tsw has evolved a LRR resembling those of phytohormone receptors LRR to induce immunity. Here we show that NSs associates with COI1, TIR1 and MAX2 through a common repressor-TCP21-which interacts directly with these phytohormone receptors. NSs enhances the interaction of COI1, TIR1 or MAX2 with TCP21 and blocks the degradation of corresponding transcriptional repressors to disable phytohormone-mediated host immunity to the virus. Tsw also interacts directly with TCP21 and this interaction is enhanced by viral NSs. Downregulation of TCP21 compromised Tsw-mediated defence against TSWV. Together, our findings reveal that a pathogen effector targets TCP21 to inhibit phytohormone receptor function, promoting virulence, and a plant NLR protein has evolved to recognize this interference as a counter-virulence strategy, thereby activating immunity.


Asunto(s)
Capsicum , Enfermedades de las Plantas , Reguladores del Crecimiento de las Plantas , Inmunidad de la Planta , Proteínas de Plantas , Receptores de Reconocimiento de Patrones , Leucina , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/virología , Reguladores del Crecimiento de las Plantas/metabolismo , Inmunidad de la Planta/inmunología , Proteínas de Plantas/química , Proteínas de Plantas/inmunología , Proteínas de Plantas/metabolismo , Receptores de Reconocimiento de Patrones/química , Receptores de Reconocimiento de Patrones/inmunología , Receptores de Reconocimiento de Patrones/metabolismo , Reconocimiento de Inmunidad Innata , Capsicum/inmunología , Capsicum/metabolismo , Capsicum/virología , Virulencia
2.
Cereb Cortex ; 34(6)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38850218

RESUMEN

Closed head injury is a prevalent form of traumatic brain injury with poorly understood effects on cortical neural circuits. Given the emotional and behavioral impairments linked to closed head injury, it is vital to uncover brain functional deficits and their driving mechanisms. In this study, we employed a robust viral tracing technique to identify the alteration of the neural pathway connecting the medial prefrontal cortex to the basolateral amygdala, and we observed the disruptions in neuronal projections between the medial prefrontal cortex and the basolateral amygdala following closed head injury. Remarkably, our results highlight that ZL006, an inhibitor targeting PSD-95/nNOS interaction, stands out for its ability to selectively reverse these aberrations. Specifically, ZL006 effectively mitigates the disruptions in neuronal projections from the medial prefrontal cortex to basolateral amygdala induced by closed head injury. Furthermore, using chemogenetic approaches, we elucidate that activating the medial prefrontal cortex projections to the basolateral amygdala circuit produces anxiolytic effects, aligning with the therapeutic potential of ZL006. Additionally, ZL006 administration effectively mitigates astrocyte activation, leading to the restoration of medial prefrontal cortex glutamatergic neuron activity. Moreover, in the context of attenuating anxiety-like behaviors through ZL006 treatment, we observe a reduction in closed head injury-induced astrocyte engulfment, which may correlate with the observed decrease in dendritic spine density of medial prefrontal cortex glutamatergic neurons.


Asunto(s)
Amígdala del Cerebelo , Ansiedad , Traumatismos Cerrados de la Cabeza , Corteza Prefrontal , Animales , Corteza Prefrontal/efectos de los fármacos , Masculino , Traumatismos Cerrados de la Cabeza/complicaciones , Ansiedad/tratamiento farmacológico , Amígdala del Cerebelo/efectos de los fármacos , Ratones , Vías Nerviosas/efectos de los fármacos , Ratones Endogámicos C57BL , Homólogo 4 de la Proteína Discs Large/metabolismo
3.
Funct Integr Genomics ; 24(2): 55, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38467948

RESUMEN

Huang Qin decoction (HQD) is a traditional Chinese medicine formula for treating colitis, but the effects and molecular mechanism of action of HQD in colitis-associated carcinogenesis (CAC) are still unclear. Therefore, we aimed to determine the beneficial effects of HQD on CAC in mice and to reveal the underlying mechanism involved. AOM/DSS was used to induce CAC in mice, and the effects of HQD on tumorigenesis in mice were examined (with mesalazine serving as a positive control). Mesalazine or HQD treatment alleviated body weight loss and decreased the disease activity index in mice induced by AOM/DSS. Mesalazine or HQD treatment also suppressed the shortening of colon tissue length, the number of tumors, and the infiltration of inflammatory cells. The genes targeted by HQD were predicted and verified, followed by knockout experiments. Elevated SLC6A4 and inhibited serotonin production and inflammation were observed in HQD-treated mice. HQD inhibited the NFκB and NLRP3/caspase1/GSDMD pathways. The therapeutic effect of HQD was diminished in SLC6A4-deficient AOM/DSS mice. Additionally, the downregulation of SLC6A4 mitigated the inhibitory effect of HQD-containing serum on MODE-K cell pyroptosis. Our findings suggest that SLC6A4 is a pivotal regulator of HQD-alleviated CAC via its modulation of the NLRP3/caspase1/GSDMD pathway.


Asunto(s)
Colitis , Scutellaria baicalensis , Ratones , Animales , Mesalamina , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Colitis/inducido químicamente , Colitis/complicaciones , Colitis/tratamiento farmacológico , Carcinogénesis/metabolismo , Ratones Endogámicos C57BL
4.
J Clin Microbiol ; : e0047924, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856218

RESUMEN

The diagnosis of invasive pulmonary fungal disease depends on histopathology and mycological culture; there are few studies on touch imprints of bronchoscopic biopsies or lung tissue biopsies for the diagnosis of pulmonary filamentous fungi infections. The purpose of the present study was to explore the detection accuracy of rapid on-site evaluation of touch imprints of bronchoscopic biopsies or lung tissue biopsies for the filamentous fungi, and it aims to provide a basis for initiating antifungal therapy before obtaining microbiological evidence. We retrospectively analyzed the diagnosis and treatment of 44 non-neutropenic patients with invasive pulmonary filamentous fungi confirmed by glactomannan assay, histopathology, and culture from February 2017 to December 2023. The diagnostic positive rate and sensitivity of rapid on-site evaluation for these filamentous fungi identification, including diagnostic turnaround time, were calculated. Compared with the final diagnosis, the sensitivity of rapid on-site evaluation was 81.8%, and the sensitivity of histopathology, culture of bronchoalveolar lavage fluid, and glactomannan assay of bronchoalveolar lavage fluid was 86.4%, 52.3%, and 68.2%, respectively. The average turnaround time of detecting filamentous fungi by rapid on-site evaluation was 0.17 ± 0.03 hours, which was significantly faster than histopathology, glactomannan assay, and mycological culture. A total of 29 (76.3%) patients received earlier antifungal therapy based on ROSE diagnosis and demonstrated clinical improvement. Rapid on-site evaluation showed good sensitivity and accuracy that can be comparable to histopathology in identification of pulmonary filamentous fungi. Importantly, it contributed to the triage of biopsies for further microbial culture or molecular detection based on the preliminary diagnosis, and the decision on early antifungal therapy before microbiological evidence is available.

5.
Cardiovasc Diabetol ; 23(1): 37, 2024 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-38245731

RESUMEN

BACKGROUND: Higher levels of palmitoyl sphingomyelin (PSM, synonymous with sphingomyelin 16:0) are associated with an increased risk of cardiovascular disease (CVD) in people with diabetes. Whether circulating PSM levels can practically predict the long-term risk of CVD and all-cause death remains unclear. This study aimed to investigate whether circulating PSM is a real predictor of CVD death in Chinese adults with or without diabetes. METHODS: A total of 286 and 219 individuals with and without diabetes, respectively, from the original Da Qing Diabetes Study were enrolled. Blood samples collected in 2009 were used as a baseline to assess circulating PSM levels. The outcomes of CVD and all-cause death were followed up from 2009 to 2020, and 178 participants died, including 87 deaths due to CVD. Cox proportional hazards regression was used to estimate HRs and their 95% CIs for the outcomes. RESULTS: Fractional polynomial regression analysis showed a linear association between baseline circulating PSM concentration (log-2 transformed) and the risk of all-cause and CVD death (p < 0.001), but not non-CVD death (p > 0.05), in all participants after adjustment for confounders. When the participants were stratified by PSM-tertile, the highest tertile, regardless of diabetes, had a higher incidence of CVD death (41.5 vs. 14.7 and 22.2 vs. 2.9 per 1000 person-years in patients with and without diabetes, respectively, all log-rank p < 0.01). Individuals with diabetes in the highest tertile group had a higher risk of CVD death than those in the lowest tertile (HR = 2.73; 95%CI, 1.20-6.22). CONCLUSIONS: Elevated PSM levels are significantly associated with a higher 10-year risk of CVD death, but not non-CVD death, in Chinese adults with diabetes. These findings suggest that PSM is a potentially useful long-term predictor of CVD death in individuals with diabetes.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus , Adulto , Humanos , Enfermedades Cardiovasculares/epidemiología , Esfingomielinas , Estudios de Seguimiento , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología , China/epidemiología , Factores de Riesgo
6.
Diabetes Obes Metab ; 26(6): 2329-2338, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38488254

RESUMEN

AIM: To evaluate whether 1-hour plasma glucose (1hPG) can be a comparable measurement to 2-hour plasma glucose (2hPG) in identifying individuals at high risk of developing diabetes. METHODS: A total of 1026 non-diabetic subjects in the Da Qing IGT and Diabetes Study were included and classified according to baseline postload 1hPG. The participants were followed up and assessed at 6-, 20- and 30year follow-up for outcomes including diabetes, all-cause and cardiovascular mortality, cardiovascular disease (CVD) events, and microvascular disease. We then conducted a proportional hazards analysis in this post hoc study to determine the risks of developing type 2 diabetes and its complications in a '1hPG-normal' group (1hPG <8.6 mmol/L) and a '1hPG-high' group (≥8.6 mmol/L). The predictive values of 1hPG and 2hPG were evaluated using a time-dependent receiver-operating characteristic (ROC) curve. RESULTS: Compared with the 1hPG-normal group, the 1hPG-high group had increased risk of diabetes (hazard ratio [HR] 4.45, 95% CI 3.43-5.79), all-cause mortality (HR 1.46, 95% CI 1.07-2.01), CVD mortality (HR 1.84, 95% CI 1.16-2.95), CVD events (HR 1.39, 95% CI 1.03-1.86) and microvascular disease (HR 1.70, 95% CI: 1.03-2.79) after adjusting for confounders. 1hPG exhibited a higher area under the ROC curve (AUC) for predicting diabetes than 2hPG during the long-term follow-up (AUC [1hPG vs. 2hPG]: 10 years: 0.86 vs. 0.84, p = 0.08; 20 years: 0.88 vs. 0.87, p = 0.04; 30 years: 0.85 vs. 0.82, p = 0.009). CONCLUSIONS: Elevated 1hPG level (≥8.6 mmol/L) was associated with increased risk of developing type 2 diabetes and its long-term complications, and could be considered as a suitable measurement for identifying individuals at high risk of type 2 diabetes.


Asunto(s)
Glucemia , Diabetes Mellitus Tipo 2 , Valor Predictivo de las Pruebas , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/sangre , Masculino , Femenino , Persona de Mediana Edad , Glucemia/análisis , Glucemia/metabolismo , Estudios de Seguimiento , China/epidemiología , Prueba de Tolerancia a la Glucosa , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/mortalidad , Intolerancia a la Glucosa/sangre , Intolerancia a la Glucosa/diagnóstico , Intolerancia a la Glucosa/complicaciones , Adulto , Complicaciones de la Diabetes/sangre , Complicaciones de la Diabetes/epidemiología , Anciano , Angiopatías Diabéticas/epidemiología , Angiopatías Diabéticas/sangre , Angiopatías Diabéticas/diagnóstico , Angiopatías Diabéticas/prevención & control , Angiopatías Diabéticas/mortalidad , Curva ROC
7.
Diabetes Obes Metab ; 26(4): 1188-1196, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38168886

RESUMEN

AIM: We aimed to investigate the long-term influence of a diet and/or exercise intervention on long-term mortality and cardiovascular disease (CVD) events. METHODS: The Da Qing Diabetes Prevention Study had 576 participants with impaired glucose tolerance (IGT) randomized to diet-only, exercise-only and diet-plus-exercise intervention group and control group. The participants underwent lifestyle interventions for 6 years. The subsequent Da Qing Diabetes Prevention Outcome Study was a prospective cohort study to follow-up the participants for up to 24 years after the end of 6-year intervention. In total, 540 participants completed the follow-up, while 36 subjects lost in follow-up. Cox proportional hazards analysis was applied to assess the influence of lifestyle interventions on targeted outcomes. RESULTS: Compared with controls, the diet-only intervention in people with IGT was significantly associated with a reduced risk of all-cause death [hazard ratio (HR) 0.77, 95% confidence interval (CI) (0.61-0.97)], CVD death [HR 0.67, 95% CI (0.46-0.97)] and CVD events [HR 0.72, 95% CI (0.54-0.96)]. The diet-plus-exercise intervention was significantly associated with a decreased risk of all-cause death [HR 0.64, 95% CI (0.48-0.84)], CVD death [HR 0.54, 95% CI (0.30-0.97)] and CVD events [HR 0.68, 95% CI (0.52-0.90)]. Unexpectedly, the exercise-only intervention was not significantly associated with the reduction of any of these outcomes, although there was a consistent trend towards reduction. CONCLUSIONS: A diet-only intervention and a diet-plus-exercise intervention in people with IGT were significantly associated with a reduced risk of all-cause death, CVD death and CVD events, while an exercise-only intervention was not. It suggests that diet-related interventions may have a potentially more reliable influence on long-term vascular complications and mortality.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Intolerancia a la Glucosa , Humanos , Intolerancia a la Glucosa/complicaciones , Intolerancia a la Glucosa/terapia , Diabetes Mellitus Tipo 2/complicaciones , Estudios Prospectivos , Incidencia , Dieta , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Enfermedades Cardiovasculares/complicaciones , Terapia por Ejercicio , Evaluación de Resultado en la Atención de Salud
9.
Appl Microbiol Biotechnol ; 108(1): 99, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38204135

RESUMEN

Ectomycorrhizal fungi (EMF) can form symbiotic relationships with plants, aiding in plant growth by providing access to nutrients and defense against phytopathogenic fungi. In this context, factors such as plant assemblages and soil properties can impact the interaction between EMF and phytopathogenic fungi in forest soil. However, there is little understanding of how these fungal interactions evolve as forests move through succession stages. In this study, we used high-throughput sequencing to investigate fungal communities in young, intermediate, and old subtropical forests. At the genus level, EMF communities were dominated by Sebacina, Russula, and Lactarius, while Mycena was the most abundant genus in pathogenic fungal communities. The relative abundances of EMF and phytopathogenic fungi in different stages showed no significant difference with the regulation of different factors. We discovered that interactions between phytopathogenic fungi and EMF maintained a dynamic balance under the influence of the differences in soil quality attributed to each forest successional stage. The community composition of phytopathogenic fungi is one of the strong drivers in shaping EMF communities over successions. In addition, the EMF diversity was significantly related to plant diversity, and these relationships varied among successional stages. Despite the regulation of various factors, the positive relationship between the diversity of phytopathogenic fungi and EMF remained unchanged. However, there is no significant difference in the ratio of the abundance of EMF and phytopathogenic fungi over the course of successions. These results will advance our understanding of the biodiversity-ecosystem functioning during forest succession. KEY POINTS: •Community composition of both EMF and phytopathogenic fungi changed significantly over forest succession. •Phytopathogenic fungi is a key driver in shaping EMF community. •The effect of plant Shannon's diversity on EMF communities changed during the forest aging process.


Asunto(s)
Agaricales , Micobioma , Micorrizas , Ecosistema , Bosques , Suelo
10.
Clin Oral Implants Res ; 35(4): 427-442, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38314615

RESUMEN

OBJECTIVE: This study aimed to synthesize zinc-incorporated nanowires structure modified titanium implant surface (Zn-NW-Ti) and explore its superior osteogenic and antibacterial properties in vitro and in vivo. MATERIALS AND METHODS: Zn-NW-Ti was synthesized via displacement reactions between zinc sulfate solutions and the titanium (Ti) surface, which was pretreated by hydrofluoric acid etching and hyperthermal alkalinization. The physicochemical properties of the Zn-NW-Ti surface were examined. Moreover, the biological effects of Zn-NW-Ti on MC3T3-E1 cells and its antibacterial property against oral pathogenic bacteria (Staphylococcus aureus, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans) compared with sandblasted and acid-etched Ti (SLA-Ti) and nanowires modified Ti (NW-Ti) surface were assessed. Zn-NW-Ti and SLA-Ti modified implants were inserted into the anterior extraction socket of the rabbit mandible with or without exposure to the mixed bacterial solution (S. aureus, P. gingivalis, and A. actinomycetemcomitans) to investigate the osteointegration and antibacterial performance via radiographic and histomorphometric analysis. RESULTS: The Zn-NW-Ti surface was successfully prepared. The resultant titanium surface appeared as a nanowires structure with hydrophilicity, from which zinc ions were released in an effective concentration range. The Zn-NW-Ti surface performed better in facilitating the adhesion, proliferation, and differentiation of MC3T3-E1 cells while inhibiting the colonization of bacteria compared with SLA-Ti and NW-Ti surface. The Zn-NW-Ti implant exhibited enhanced osseointegration in vivo, which was attributed to increased osteogenic activity and reduced bacterial-induced inflammation compared with the SLA-Ti implant. CONCLUSIONS: The Zn-incorporated nanowires structure modified titanium implant surface exhibited improvements in osteogenic and antibacterial properties, which optimized osteointegration in comparison with SLA titanium implant surface.


Asunto(s)
Implantes Dentales , Nanocables , Animales , Conejos , Titanio/farmacología , Titanio/química , Staphylococcus aureus , Antibacterianos/farmacología , Oseointegración , Bacterias , Zinc/química , Zinc/farmacología , Propiedades de Superficie , Osteogénesis
11.
J Environ Manage ; 359: 121041, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38703651

RESUMEN

Bisphenol analogues (BPs) have gained increasing attention in recent years due to their ubiquitousness and potential endocrine disrupting properties in environments. However, little information is available on their spatiotemporal distribution, source apportionment and ecological risk in river sediments, especially the case in river basins with a high population density and those typical regions with agricultural-urban gradient, where land use patterns and intensity of human activity are varying. In this study, field investigations of BPs in the sediment of the entire Qinhuai River Basin, a typical agricultural-suburban agricultural-urban gradient area, were conducted before and after the flood period. Thirty-two sites were sampled for six types of BPs, resulted in no significant difference in the concentration of ΣBPs between the two periods, with ΣBPs ranging from 3.92 to 151 ng/g and 2.16-59.0 ng/g, respectively. Bisphenol A (BPA) was the main contributor. Whereas a multivariate analysis of variance (MANOVA) suggested that the composition structure of BPs had been influenced by water periods. The land use patterns had an impact on the distribution of ΣBPs in river sediments, which was more significant in after the flood period, with ΣBPs in urban rivers was 1.85 times, 3.44 times, and 3.08 times higher than the suburban rivers, agricultural rivers, and reservoirs, respectively. Yet land use types did not significantly alter the composition structure of BPs. The correlation analysis between BPs and the physicochemical properties of sediments showed a significant positive correlation between BPA and total organic carbon (TOC). The positive matrix factorization model (PMF) suggested that BPs in sediments of the basin might be influenced by industrial coatings, textiles, electronics and biopharmaceuticals, as well as urban wastewater or solid waste generated from daily life. The ecological risk assessment posed by BPA, based on the risk quotient, indicated that the ecological risk of BPA in sediments was low for three indicator benthic organisms: crustaceans, worms, and mollusks. However, the risk of BPA in river sediments varied among different land use patterns, with the risk ranking as follows: reservoirs < agricultural rivers < suburban rivers < urban rivers.


Asunto(s)
Compuestos de Bencidrilo , Monitoreo del Ambiente , Sedimentos Geológicos , Fenoles , Ríos , Contaminantes Químicos del Agua , Ríos/química , Fenoles/análisis , Compuestos de Bencidrilo/análisis , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos/química , Sedimentos Geológicos/análisis , Disruptores Endocrinos/análisis
12.
J Environ Manage ; 362: 121312, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38824888

RESUMEN

Ectomycorrhizal (EcM) fungi play an important role in nutrient cycling and community ecological dynamics and are widely acknowledged as important components of forest ecosystems. However, little information is available regarding EcM fungal community structure or the possible relationship between EcM fungi, soil properties, and forestry activities in Pinus massoniana forests. In this study, we evaluated soil properties, extracellular enzyme activities, and fungal diversity and community composition in root and soil samples from pure Pinus massoniana natural forests, pure P. massoniana plantations, and P. massoniana and Liquidambar gracilipes mixed forests. The mixed forest showed the highest EcM fungal diversity in both root and bulk soil samples. Community composition and co-occurrence network structures differed significantly between forest types. Variation in the EcM fungal community was significantly correlated with the activities of ß-glucuronidase and ß-1,4-N-acetylglucosaminidase, whereas non-EcM fungal community characteristics were significantly correlated with ß-1,4-glucosidase and ß-glucuronidase activities. Furthermore, stochastic processes predominantly drove the assembly of both EcM and non-EcM fungal communities, while deterministic processes exerted greater influence on soil fungal communities in mixed forests compared to pure forests. Our findings may inform a deeper understanding of how the assembly processes and environmental roles of subterranean fungal communities differ between mixed and pure plantations and may provide insights for how to promote forest sustainability in subtropical areas.


Asunto(s)
Bosques , Micorrizas , Pinus , Microbiología del Suelo , Pinus/microbiología , Suelo/química , Biodiversidad , Hongos , Ecosistema
13.
J Biol Chem ; 298(9): 102372, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35970391

RESUMEN

Nitrogen (N2) gas in the atmosphere is partially replenished by microbial denitrification of ammonia. Recent study has shown that Alcaligenes ammonioxydans oxidizes ammonia to dinitrogen via a process featuring the intermediate hydroxylamine, termed "Dirammox" (direct ammonia oxidation). However, the unique biochemistry of this process remains unknown. Here, we report an enzyme involved in Dirammox that catalyzes the conversion of hydroxylamine to N2. We tested previously annotated proteins involved in redox reactions, DnfA, DnfB, and DnfC, to determine their ability to catalyze the oxidation of ammonia or hydroxylamine. Our results showed that none of these proteins bound to ammonia or catalyzed its oxidation; however, we did find DnfA bound to hydroxylamine. Further experiments demonstrated that, in the presence of NADH and FAD, DnfA catalyzed the conversion of 15N-labeled hydroxylamine to 15N2. This conversion did not happen under oxygen (O2)-free conditions. Thus, we concluded that DnfA encodes a hydroxylamine oxidase. We demonstrate that DnfA is not homologous to any known hydroxylamine oxidoreductases and contains a diiron center, which was shown to be involved in catalysis via electron paramagnetic resonance experiments. Furthermore, enzyme kinetics of DnfA were assayed, revealing a Km of 92.9 ± 3.0 µM for hydroxylamine and a kcat of 0.028 ± 0.001 s-1. Finally, we show that DnfA was localized in the cytoplasm and periplasm as well as in tubular membrane invaginations in HO-1 cells. To the best of our knowledge, we conclude that DnfA is the first enzyme discovered that catalyzes oxidation of hydroxylamine to N2.


Asunto(s)
Alcaligenes , Amoníaco , Hidroxilaminas , Oxidorreductasas , Alcaligenes/enzimología , Amoníaco/metabolismo , Proteínas Bacterianas/metabolismo , Flavina-Adenina Dinucleótido/metabolismo , Hidroxilaminas/metabolismo , NAD/metabolismo , Nitrógeno/metabolismo , Oxidación-Reducción , Oxidorreductasas/metabolismo , Oxígeno
14.
Anal Chem ; 95(46): 16996-17002, 2023 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-37943990

RESUMEN

In the field of array sensing, researchers are committed to miniaturizing array sensing systems while ensuring the acquisition of multiple sensing information. Here, a new strategy called "stimulus responsive array sensing" was presented to obtain virtual multiple sensing without constructing multiple physical sensing units. Based on bioluminescence resonance energy transfer, where luciferase acts as the donor and temperature stimulus response polymers act as the receptors, by using only one sensing unit to output multiple stimulus responsive sensing signals in temperature dimension, an equivalent array sensing could be achieved. This strategy can distinguish and quantify a variety of proteins. More importantly, glucose responsive monomers were doped in polymers; thus, more virtual sensing units can be further increased to obtain more sensing signals, greatly increasing the accuracy of protein recognition, and it can also be used to differentiate several compositions of protein under different glucose concentrations in urine caused by different renal diseases. The results show the potential of the "stimulus responsive array sensing" for analyzing molecular compositions in complex biological systems and show a new tack in array sensing.


Asunto(s)
Polímeros , Proteínas , Temperatura , Glucosa
15.
Small ; 19(49): e2207606, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37605335

RESUMEN

Primary cancer modulates the bone microenvironment to sow the seeds of dormancy and metastasis in tumor cells, leading to multiple organ metastasis and death. In this study, 3D printing and bone-on-a-chip (BOC) are combined to develop a BOC platform that mimics the pre-metastatic niches (PMNs) and facilitates elucidation of the interactions between bone-resident cells and metastatic tumor cells under the influence of primary cancer. Photocrosslinkable gelatin methacrylate (GelMA) is used as a 3D culturing hydrogel to encapsulate cells, and circulate tumor culture medium (CM) adjacent to the hydrogel to verify the critical role of mesenchymal stem cells (MSCs) and osteoclasts (RAW264.7s). Three niches: the dormancy niche, the perivascular niche, and the "vicious cycle" niche, are devised to recapitulate bone metastasis in one chip with high cell viability and excellent nutrient exchange. With respect to tumor dormancy and reactivation, the invadopodia formation of A549 lung cancer cells in communication with MSCs and RAW264.7 via the cortactin pathway is researched. As a proof of concept, the functionality and practicality of the platform are demonstrated by analyzing the invadopodia formation and the influence of various cells, and the establishment of the dynamic niches paves the way to understanding PMN formation and related drug discovery.


Asunto(s)
Neoplasias Óseas , Neoplasias Pulmonares , Humanos , Microfluídica , Neoplasias Óseas/patología , Hidrogeles , Dispositivos Laboratorio en un Chip , Microambiente Tumoral
16.
Small ; 19(40): e2302885, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37264726

RESUMEN

The adjustment of the valence state of metal ions is crucial for various applications because peculiar activity originates from metal ions with specific valence. Cu+ can interact with molecules possessing unsaturated bonds like CO via π-complexation, while Cu2+ doesn't have such ability. Meanwhile, Cu+ sites are easily oxidized to Cu2+ , leading to the loss of activity. Despite great efforts, the development of a facile method to construct and recover Cu+ sites remains a pronounced challenge. Here, for the first time a facile photo-induced strategy is reported to fabricate Cu+ sites in metal-organic frameworks (MOFs) and recover Cu+ after oxidation. The Cu2+ precursor was loaded on NH2 -MIL-125, a typical visible-light responsive Ti-based MOF. Visible light irradiation triggers the formation of Ti3+ from Ti4+ in framework, which reduces the supported Cu2+ in the absence of any additional reducing agent, thus simplifying the process for Cu+ generation significantly. Due to π-complexation interaction, the presence of Cu+ results in remarkably enhanced CO capture capacity (1.16 mmol g-1 ) compared to NH2 -MIL-125 (0.49 mmol g-1 ). More importantly, Cu+ can be recovered conveniently via re-irradiation when it is oxidized to Cu2+ , and the oxidation-recovery process is reversible.

17.
Toxicol Appl Pharmacol ; 478: 116708, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37778480

RESUMEN

Pentachlorophenol (PCP) is a ubiquitous environmental toxicant with various adverse effects. Although its neurotoxicity has been reported, the underlying mechanism and subsequent detoxification remain unclear. In this study, embryos and adult zebrafish were exposed to PCP to determine its potential neurotoxic mechanism and protective indicators. The survival rate, heart rate, mobility time, active status and moving distance were significantly decreased in larvae after 30 µg/L PCP exposure. Likewise, the mobile time, latency to the first movement, velocity and moving distance of adult zebrafish were significantly reduced by PCP exposure. Untargeted metabolomics analysis of larvae revealed that arginine and proline metabolism was the primary pathway affected by PCP exposure, reflected by increased proline and decreased citrulline (CIT) contents, which were confirmed by quantitative data. PCP exposure suppressed the conversion from arginine to CIT in larvae by downregulating the expression of nos1 and nos2a. Ornithine content was increased in the brains and intestines of adult zebrafish after PCP exposure, which inhibited ornithine catabolism to CIT by downregulating otc, resulting in reduced CIT. Intriguingly, CIT supplementation significantly restored the neurobehavioral defects induced by PCP in larvae and adult zebrafish. CIT supplementation upregulated the expression of ef1α and tuba1 in larvae and inhibited the downregulation of ef1α in the brains of adult zebrafish. Taken together, these results indicated that CIT supplementation could protect against PCP-induced neurotoxicity by upregulating the expression of genes involved in neuronal development and function.


Asunto(s)
Pentaclorofenol , Animales , Pentaclorofenol/farmacología , Pentaclorofenol/toxicidad , Pez Cebra/metabolismo , Citrulina/metabolismo , Citrulina/farmacología , Larva , Arginina/metabolismo , Arginina/farmacología , Ornitina/metabolismo , Ornitina/farmacología , Prolina/metabolismo , Prolina/farmacología
18.
BMC Cancer ; 23(1): 743, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37568077

RESUMEN

BACKGROUND: The prognostic role of either forkhead box A1 (FOXA1) or anterior gradient 2 (AGR2) in breast cancer has been found separately. Considering that there were interplays between them depending on ER status, we aimed to assess the statistical interaction between AGR2 and FOXA1 on breast cancer prognosis and examine the prognostic role of the combination of them by ER status. METHODS: AGR2 and FOXA1 expression in tumor tissues were evaluated with tissue microarrays by immunohistochemistry in 915 breast cancer patients with follow up data. The expression levels of these two markers were treated as binary variables, and many different cutoff values were tried for each marker. Survival and Cox proportional hazard analyses were used to evaluate the relationship between AGR2, FOXA1 and prognosis, and the statistical interaction between them on the prognosis was assessed on multiplicative scale. RESULTS: Statistical interaction between AGR2 and FOXA1 on the PFS was significant with all the cutoff points in ER-positive breast cancer patients but not ER-negative ones. Among ER-positive patients, the poor prognostic role of the high level of FOXA1 was significant only in patients with the low level of AGR2, and vice versa. When AGR2 and FOXA1 were considered together, patients with low levels of both markers had significantly longer PFS compared with all other groups. CONCLUSIONS: There was a statistical interaction between AGR2 and FOXA1 on the prognosis of ER-positive breast cancer. The combination of AGR2 and FOXA1 was a more useful marker for the prognosis of ER-positive breast cancer patients.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Pronóstico , Mama/patología , Inmunohistoquímica , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Biomarcadores de Tumor/metabolismo , Mucoproteínas , Proteínas Oncogénicas
19.
Nitric Oxide ; 136-137: 24-32, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37217001

RESUMEN

Developing functional nitroxyl (HNO) donors play a significant role in the further exploration of endogenous HNO in biochemistry and pharmacology. In this work, two novel Piloty's acids (SBD-D1 and SBD-D2) were proposed by incorporating benzoxadiazole-based fluorophores, in order to achieve the dual-function of releasing both HNO and a fluorophore in situ. Under physiological conditions, both SBD-D1 and SBD-D2 efficiently donated HNO (t1/2 = 10.96 and 8.18 min, respectively). The stoichiometric generation of HNO was determined by both Vitamin B12 and phosphine compound trap. Interestingly, due to the different substitution groups on the aromatic ring, SBD-D1 with the chlorine showed no fluorescence emission, but SBD-D2 was strongly fluorescent due to the presence of the dimethylamine group. Specifically, the fluorescent signal would decrease during the release process of HNO. Moreover, theoretical calculations were performed to understand the emission difference. A strong radiation derived from benzoxadiazole with dimethylamine group due to the large transition dipole moment (∼4.3 Debye), while the presence of intramolecular charge transfer process in the donor with chlorine group caused a small transition dipole moment (<0.1 Debye). Finally, these studies would contribute to the future design and application of novel functional HNO donors for the exploration of HNO biochemistry and pharmacology.


Asunto(s)
Cloro , Óxidos de Nitrógeno , Óxidos de Nitrógeno/química , Ácidos Hidroxámicos/química , Colorantes Fluorescentes
20.
Diabetes Obes Metab ; 25 Suppl 1: 34-42, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36775931

RESUMEN

AIMS: To investigate the impact of stress hyperglycaemia (SH) on in-hospital adverse cardiac events after coronary artery bypass grafting (CABG) in patients without diabetes. MATERIALS AND METHODS: In total, 5450 patients without diabetes who underwent CABG were analysed. SH was defined as any two instances in which the random blood glucose level was >7.8 mmol/L after CABG in the intensive care unit (ICU). The primary outcome was major adverse cardiac events (MACEs), including in-hospital mortality, acute myocardial infarction, stroke and acute renal failure. Secondary outcomes included surgical site infection (SSI) and length of ICU stay. RESULTS: Patients with SH had higher rates of MACEs (5.7% vs. 2.3%, p < .0001) and higher SSI (3.3% vs. 1.4%, p = .0003) and longer ICU stays (2.6 ± 2.0 vs. 1.3 ± 1.3 days, p < .0001) than those without SH. Furthermore, SH was associated with a higher risk of MACEs [odds ratio (OR): 2.32, 95% confidence interval (CI): 1.38-3.90], SSI (OR: 2.21, 95% CI: 1.20-3.95) and longer ICU stay (OR: 12.27, 95% CI: 9.41-16.92) after adjusting for confounders. Subgroup analysis showed that patients with SH >10 mmol/L or SH that occurred in the ICU and lasted more than 48 h had increased risks of postoperative complications (p < .05). CONCLUSIONS: SH was significantly associated with an increased risk of MACEs, SSI and longer ICU stay after CABG in patients without diabetes. In addition, SH >10 mmol/L or that occurred in the ICU and lasted more than 48 h increased the risk of adverse outcomes.


Asunto(s)
Enfermedad de la Arteria Coronaria , Diabetes Mellitus , Hiperglucemia , Infarto del Miocardio , Humanos , Hiperglucemia/complicaciones , Hiperglucemia/epidemiología , Enfermedad de la Arteria Coronaria/complicaciones , Puente de Arteria Coronaria/efectos adversos , Diabetes Mellitus/etiología , Infarto del Miocardio/complicaciones , Infarto del Miocardio/epidemiología , Estudios Retrospectivos , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA