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1.
Methods Mol Biol ; 2841: 1-17, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39115761

RESUMEN

Protein secretion mediated by the secretory transport pathway is a sophisticated and highly regulated cellular process in eukaryotic cells. In the conventional secretory transport pathway, newly synthesized proteins pass through several endomembrane compartments to reach their destinations. This transport occurs via small, membrane-enclosed vesicles. To ensure the fidelity of trafficking, eukaryotic cells employ elaborate molecular machinery to accurately sort newly synthesized proteins into specific transport vesicles and precisely deliver them to respective acceptor compartments. Leaderless cargo proteins, lacking a signal peptide, follow an unconventional secretory pathway. This review encompasses the molecular machinery regulating both conventional and unconventional protein secretion in yeast and animal cells.


Asunto(s)
Transporte de Proteínas , Vías Secretoras , Animales , Saccharomyces cerevisiae/metabolismo , Humanos , Levaduras/metabolismo , Proteínas/metabolismo
2.
Turk J Gastroenterol ; 35(7): 587-588, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39128110

RESUMEN

Cite this article as: Zong Z, Xu J, Zhang H, Xu H, Tang X, Shi L. A small "tent" in the esophagus. Turk J Gastroenterol. 2024;35(7): 587-588.


Asunto(s)
Esófago , Humanos , Masculino , Enfermedades del Esófago , Femenino
3.
Sci Total Environ ; 950: 175233, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39102955

RESUMEN

Accurate forecast of fine particulate matter (PM2.5) is crucial for city air pollution control, yet remains challenging due to the complex urban atmospheric chemical and physical processes. Recently deep learning has been routinely applied for better urban PM2.5 forecasts. However, their capacity to represent the spatiotemporal urban atmospheric processes remains underexplored, especially compared with traditional approaches such as chemistry-transport models (CTMs) and shallow statistical methods other than deep learning. Here we probe such urban-scale representation capacity of a spatiotemporal deep learning (STDL) model for 24-hour short-term PM2.5 forecasts at six urban stations in Rizhao, a coastal city in China. Compared with two operational CTMs and three statistical models, the STDL model shows its superiority with improvements in all five evaluation metrics, notably in root mean square error (RMSE) for forecasts at lead times within 12 h with reductions of 49.8 % and 47.8 % respectively. This demonstrates the STDL model's capacity to represent nonlinear small-scale phenomena such as street-level emissions and urban meteorology that are in general not well represented in either CTMs or shallow statistical models. This gain of small-scale representation in forecast performance decreases at increasing lead times, leading to similar RMSEs to the statistical methods (linear shallow representations) at about 12 h and to the CTMs (mesoscale representations) at 24 h. The STDL model performs especially well in winter, when complex urban physical and chemical processes dominate the frequent severe air pollution, and in moisture conditions fostering hygroscopic growth of particles. The DL-based PM2.5 forecasts align with observed trends under various humidity and wind conditions. Such investigation into the potential and limitations of deep learning representation for urban PM2.5 forecasting could hopefully inspire further fusion of distinct representations from CTMs and deep networks to break the conventional limits of short-term PM2.5 forecasts.

4.
J Exp Bot ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39126211

RESUMEN

The endoplasmic reticulum (ER) is crucial for maintaining cell homeostasis because it is the primary site for synthesizing secreted and transmembrane proteins and lipids. The unfolded protein response (UPR) is activated to restore ER homeostasis under ER stress. However, the relationship between lipids and the ER stress response in plants is not well understood. Arabidopsis Golgi anti-apoptotic proteins (GAAPs) are involved in resisting ER stress. To elucidate the function of GAAPs, PASTICCINO2 (PAS2), involved in very long-chain fatty acid (VLCFA) synthesis, was found to interact with GAAPs and IRE1. Single pas2 and gaap1/gaap2pas2 double mutants exhibited increased seedling damage and impaired UPR response under chronic ER stress. Site mutation combined with genetic analysis revealed that the role of PAS2 in resisting ER stress depended on its VLCFA synthesis domain. VLCFA contents were upregulated under ER stress, which required GAAPs. Exogenous VLCFAs partially restored the defect in UPR upregulation caused by PAS2 or GAAP mutations under chronic ER stress. These findings demonstrate that the association of PAS2 with GAAPs confers plant resistance to ER stress by regulating VLCFA synthesis and the UPR. This provides a basis for further studies on the connection between lipids and cell fate decisions under stress.

5.
Am J Clin Pathol ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39110416

RESUMEN

OBJECTIVES: To examine the associated risk of cervical intraepithelial neoplasm grade 3+ (CIN3+) lesions in patients with AGC and extensive human papillomavirus (HPV) genotyping. METHODS: Cases with atypical glandular cell (AGC) interpretation on a Papanicolaou (Pap) test were identified along with associated extensive HPV genotyping and histologic follow-up results. RESULTS: Within this cohort of 469,694 Pap tests, 0.4% were diagnosed as AGCs. In total, 1267 cases had concurrent high-risk HPV (hrHPV) genotyping, and 40.3% were hrHPV positive. The percentage of AGC cases with cervical CIN3+ on histologic follow-up was 52.2% when hrHPV was positive, whereas it was 4.9% with a negative hrHPV result. The top 5 hrHPV genotypes associated with cervical CIN3+ in this cohort were HPV16, HPV18, HPV58, HPV52, and HPV33. Indeed, 92.8% of the hrHPV-associated CIN3+ lesions identified in this cohort were positive for at least one of these HPV genotypes. The sensitivity of detecting cervical CIN3+ lesions was 85.6% with the top 5 hrHPV genotypes (HPV16/18/58/52/33) and only increased to 89.0% when the additional 12 genotypes were included. CONCLUSIONS: In patients with an AGC Pap, the risk of having a cervical CIN3+ lesion is greatly increased by positivity for hrHPV types 16, 18, 58, 52, and/or 33. Incorporating comprehensive HPV genotyping into AGC cytology allows for refined risk stratification and more tailored management strategies.

6.
J Asthma Allergy ; 17: 601-609, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38947955

RESUMEN

Purpose: To investigate the patterns of allergens in allergic conjunctivitis (AC) and the association with allergic comorbidity. Methods: This retrospective cross-sectional study enrolled 2972 children with AC. Clinical data, including sex, age, allergic comorbidities (allergic asthma, allergic rhinitis, and atopic dermatitis), and serum allergen-specific immunoglobulin E (sIgE), were collected from the electronic medical record (EMR). The categorical variables were compared with the chi-square test. The characteristics of allergens in children of different ages and comorbidities were analyzed by trend chi-square. The sensitivity level of HDM associated with AC and comorbidities was assessed by odds ratios (ORs) with 95% confidence intervals of logistic regression analysis. Results: A total of 2972 children (2015 boys and 957 girls) with AC were included in the study. The mean age was 3.78 (0.5~12) years. The most common allergen was house dust mite(HDM) (43.41%). With age, the positive rate for inhaled allergens gradually increased, and the positive rate for ingested allergens decreased. With the number of comorbidities increasing, the positive rates of sensitization were 38.33%, 74.51%, 80.72%, and 89.05%, and the incidence of polysensitization was 44.66%, 56.48%, 59.54%, and 74.59%, respectively. With the increase of HDM-sIgE level, the number of comorbidities and the risk increased gradually. Conclusion: HDM is the most common allergen in AC children of different ages. High levels of HDM-sIgE may be a predictor for allergic comorbidities. Children with polysensitization and high levels of HDM sIgE will be an important target population for future intervention in other allergy-related disease prevention.

7.
Adv Med Educ Pract ; 15: 599-607, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948484

RESUMEN

Objective: To investigate the effectiveness of flipped classrooms (FC) based on outcomes-based education (OBE) on clinical ophthalmology clerkships. Methods: Ninety-nine undergraduates were non-randomly assigned to the FC based on the OBE (FC-OBE) group or traditional lecture (TL) group in the ophthalmology clerkship. Pre- and post-tests were performed to assess student learning outcomes. Anonymous questionnaires were collected to compare students' attitudes and classroom engagements between the two groups. Results: More participants agreed FC-OBE was helpful in developing teamwork ability and knowing the work standard. Teaching staff in the FC-OBE classroom received higher evaluations. More participants in the FC-OBE group had higher classroom engagement in skills and emotions than in the TL group. The post-class test scores, mainly case analysis scores were higher in the FC-OBE group than in the TL group. Conclusion: FC-OBE classroom improves student engagement and clinical analysis competence in undergraduate ophthalmology clerkship.

8.
Front Immunol ; 15: 1427739, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39026681

RESUMEN

Lactylation is a process where lactate, a cellular metabolism byproduct, is added to proteins, altering their functions. In the realm of macrophage activation, lactylation impacts inflammatory response and immune regulation. Understanding the effects of lactylation on macrophage activation is vital in lung diseases, as abnormal activation and function are pivotal in conditions like pneumonia, pulmonary fibrosis, COPD, and lung cancer. This review explores the concept of lactylation, its regulation of macrophage activation, and recent research progress in lung diseases. It offers new insights into lung disease pathogenesis and potential therapeutic targets.


Asunto(s)
Enfermedades Pulmonares , Activación de Macrófagos , Humanos , Activación de Macrófagos/inmunología , Animales , Enfermedades Pulmonares/inmunología , Enfermedades Pulmonares/metabolismo , Ácido Láctico/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo
9.
Blood ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39028876

RESUMEN

Abatacept plus calcineurin inhibitors/methotrexate (CNI/MTX) is the first FDA-approved regimen for acute graft-versus-host disease (aGVHD) prophylaxis during unrelated-donor hematopoietic cell transplantation (URD-HCT). We investigated its impact in URD-HCT patients using Center for International Blood and Marrow Transplant Research data for 7/8-human leukocyte antigen (HLA)-mismatched (MMUD) or 8/8-HLA-matched (MUD) URD-HCT recipients between 2011-2018. Primary outcomes included day-180, 1-year, and 2-year overall survival (OS) and relapse-free survival (RFS) for abatacept+CNI/MTX vs CNI/MTX, CNI/MTX+antithymocyte globulin (ATG), and post-transplant cyclophosphamide-based prophylaxis (PT-Cy); other outcomes included aGVHD, chronic GVHD, non-relapse mortality, and relapse. For 7/8-MMUDs, day-180 OS (primary endpoint supporting FDA approval) was significantly higher for abatacept+CNI/MTX vs CNI/MTX (98%vs75%; p=0.0028). Two-year OS was significantly higher for abatacept+CNI/MTX vs CNI/MTX (83%vs55%; p=0.0036), CNI/MTX+ATG (83%vs46%; p=0.0005) and similar to PT-Cy (80%vs68%; p=0.2325). Two-year RFS was significantly higher for abatacept+CNI/MTX vs CNI/MTX (74%vs49%; p=0.0098) and CNI/MTX+ATG (77%vs35%; p=0.0002), and similar vs PT-Cy (72%vs56%; p=0.1058). For 8/8-MUDs, 2-year OS was similar with abatacept+CNI/MTX vs CNI/MTX (70%vs62%; p=0.2569), CNI/MTX+ATG (75%vs64%; p=0.1048), and PT-Cy (74%vs69%; p=0.5543). Two-year RFS for abatacept+CNI/MTX was numerically higher vs CNI/MTX (63%vs52%; p=0.1497) with an improved hazard ratio (HR: 0.46 [0.25-0.86]), and vs CNI/MTX+ATG (66%vs55%; p=0.1193; HR: 0.39 [0.21-0.73]). Two-year RFS was similar vs PT-Cy (68%vs57%; p=0.2356; HR: 0.54 [0.26-1.11]). For both 7/8-MMUD and 8/8-MUD recipients, abatacept+CNI/MTX prophylaxis improved survival outcomes vs CNI/MTX and CNI/MTX+ATG; outcomes were similar to PT-Cy-based regimens. Abatacept+CNI/MTX has potential to facilitate unrelated donor pool expansion for HCT.

10.
Nat Commun ; 15(1): 5855, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38997298

RESUMEN

Plasmonic materials can generate strong electromagnetic fields to boost the Raman scattering of surrounding molecules, known as surface-enhanced Raman scattering. However, these electromagnetic fields are heterogeneous, with only molecules located at the 'hotspots', which account for ≈ 1% of the surface area, experiencing efficient enhancement. Herein, we propose patterned plasmonic trimers, consisting of a pair of plasmonic dimers at the bilateral sides and a trap particle positioned in between, to address this challenge. The trimer configuration selectively directs probe molecules to the central traps where 'hotspots' are located through chemical affinity, ensuring a precise spatial overlap between the probes and the location of maximum field enhancement. We investigate the Raman enhancement of the Au@Al2O3-Au-Au@Al2O3 trimers, achieving a detection limit of 10-14 M of 4-methylbenzenethiol, 4-mercaptopyridine, and 4-aminothiophenol. Moreover, single-molecule SERS sensitivity is demonstrated by a bi-analyte method. Benefiting from this sensitivity, our approach is employed for the early detection of lung tumors using fresh tissues. Our findings suggest that this approach is sensitive to adenocarcinoma but not to squamous carcinoma or benign cases, offering insights into the differentiation between lung tumor subtypes.


Asunto(s)
Oro , Neoplasias Pulmonares , Nanopartículas del Metal , Espectrometría Raman , Espectrometría Raman/métodos , Neoplasias Pulmonares/diagnóstico , Oro/química , Humanos , Nanopartículas del Metal/química , Compuestos de Sulfhidrilo/química , Compuestos de Anilina/química , Adenocarcinoma/diagnóstico , Límite de Detección , Piridinas/química
11.
Molecules ; 29(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38998992

RESUMEN

A new binuclear Gd(III) complex, [Gd2(L)6(Phen)2]·4H2O, was synthesized via the reaction of gadolinium(III) nitrate hexahydrate, 4-acetylphenoxyacetic acid (HL), NaOH, and 1,10-phenanthroline (Phen) in a solution of water-ethanol (v:v = 1:1). The Gd(III) complex was characterized using IR, UV-vis, TG-DSC, fluorescence, and single-crystal X-ray diffraction analyses. The results showed that the Gd(III) complex crystallizes in the triclinic system, space group P-1, and each Gd(III) ion was coordinated with two nitrogen atoms (N1, N2, or N1a, and N2a) from two Phen ligands and seven oxygen atoms (O1, O2, O7a, O9, O8, O8a, O10a, or O1a, O2a, O7, O8, O8a, O9a, and O10) from six L ligands, respectively, forming a nine-coordinated coordination mode. The Gd(III) complex molecules formed a one-dimensional chained and three-dimensional network structure via benzenering π-π stacking. The Hirschfeld surface analysis and the calculations of the electron density distributions of the frontier molecular orbitals of the Gd(III) complex were performed. The catalytic activities of the photocatalytic CO2 reduction and benzyl alcohol oxidation using the Gd(III) complex as a catalyst were performed. The results of the photocatalytic CO2 reduction showed that the yield and the selectivity of CO reached 41.5 µmol/g and more than 99% after four hours, respectively. The results of the benzyl alcohol oxidation showed that the yield of benzaldehyde was 45.7% at 120 °C with THF as the solvent under 0.5 MPa O2 within 2 h.

12.
Int J Colorectal Dis ; 39(1): 108, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008124

RESUMEN

BACKGROUND AND AIMS: Video-assisted anal fistula treatment (VAAFT) is an innovative surgical approach enabling the direct visualization of the fistula tract structure. This study aims to assess the efficacy of VAAFT in comparison with that of traditional surgical methods and explore potential risk factors contributing to fistula recurrence to provide new recommendations for surgical selection. MATERIALS AND METHODS: Information was collected from 100 patients with complex anal fistula (CAF) in our hospital who underwent surgical treatment from January 2021 to January 2023. We compared the baseline information and surgical outcomes of two groups, analyzed the risk factors for fistula recurrence by using logistic regression analysis, and conducted further exploration by using the body mass index. RESULTS: Equal numbers of patients underwent VAAFT and traditional surgeries, and no significant differences in baseline information were observed. Patients who received VAAFT experienced less intraoperative bleeding (15.5 (14.0-20.0) vs. 32.0 (25.0-36.0)), shorter hospital stays (2.0 (2.0-2.5) vs. 3.0 (3.0-3.5)), reduced postoperative pain and wound discharge, but longer operative times (43.3 ± 6.9 vs. 35.0 (31.5-40.0)) compared with patients who underwent traditional surgeries. No significant differences in recurrence rates were found three and six months after operation (the p-values were 0.790 and 0.806, respectively). However, the Wexner scores of the VAAFT group were significantly low in the first follow-up (0 (0-1.0) vs. 2.0 (1.0-2.0)). Postoperative recurrence of fistulas may be associated with obesity (p-value = 0.040), especially in patients undergoing traditional surgeries (p-value = 0.036). CONCLUSION: VAAFT offers advantages, such as less pain, less trauma, and faster recovery, compared with traditional surgical treatment. Obese patients with CAF are prone to recurrence, and we recommend that they undergo VAAFT treatment rather than traditional surgeries.


Asunto(s)
Obesidad , Fístula Rectal , Recurrencia , Cirugía Asistida por Video , Humanos , Fístula Rectal/cirugía , Fístula Rectal/etiología , Obesidad/complicaciones , Obesidad/cirugía , Femenino , Masculino , Resultado del Tratamiento , Persona de Mediana Edad , Adulto , Factores de Riesgo , Índice de Masa Corporal , Tempo Operativo , Tiempo de Internación
13.
Sensors (Basel) ; 24(14)2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39065918

RESUMEN

Ultrasonic flow meters are crucial measuring instruments in natural gas transportation pipeline scenarios. The collected flow velocity data, along with the operational conditions data, are vital for the analysis of the metering performance of ultrasonic flow meters and analysis of the flow process. In practical applications, high requirements are placed on the modeling accuracy of ultrasonic flow meters. In response, this paper proposes an ultrasonic flow meter modeling method based on a combination of data learning and industrial physics knowledge. This paper builds ultrasonic flow meter flow velocity prediction models under different working conditions, combining pipeline flow field velocity distribution knowledge for data preprocessing and loss function design. By making full use of the characteristics of the physics and data learning, the prediction results are close to the real acoustic path flow velocity distribution; thus, the model has high accuracy and interpretability. Experiments are conducted to prove that the prediction error of the proposed method can be controlled within 1%, which can meet the needs of ultrasonic flow meter modeling and subsequent performance analysis in actual production.

14.
Genes (Basel) ; 15(7)2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39062743

RESUMEN

Most species of Papilionidae are large and beautiful ornamental butterflies. They are recognized as model organisms in ecology, evolutionary biology, genetics, and conservation biology but present numerous unresolved phylogenetic problems. Complete mitochondrial genomes (mitogenomes) have been widely used in phylogenetic studies of butterflies, but mitogenome knowledge within the family Papilionidae is limited, and its phylogeny is far from resolved. In this study, we first report the mitogenome of Byasa confusa from the subfamily Papilioninae of Papilionidae. The mitogenome of B. confusa is 15,135 bp in length and contains 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and an AT-rich control region (CR), closely mirroring the genomic structure observed in related butterfly species. Comparative analysis of 77 Papilionidae mitogenomes shows gene composition and order to be identical to that of an ancestral insect, and the AT bias, Ka/Ks, and relative synonymous codon usage (RSCU) are all consistent with that of other reported butterfly mitogenomes. We conducted phylogenetic analyses using maximum-likelihood (ML) and Bayesian-inference (BI) methods, with 77 Papilionidae species as ingroups and two species of Nymphalidae and Lycaenidae as outgroups. The phylogenetic analysis indicated that B. confusa were clustered within Byasa. The phylogenetic trees show the monophyly of the subfamily Papilioninae and the tribes Leptocircini, Papilionini, and Troidini. The data supported the following relationships in tribe level on Papilioninae: (((Troidini + Papilionini) + Teinopalpini) + Leptocircini). The divergence time analysis suggests that Papilionidae originated in the late Creataceous. Overall, utilizing the largest number of Papilionidae mitogenomes sequenced to date, with the current first exploration in a phylogenetic analysis on Papilionidae (including four subfamilies), this study comprehensively reveals the mitogenome characteristics and mitogenome-based phylogeny, providing information for further studies on the mitogenome, phylogeny, evolution, and taxonomic revision of the Papilionidae family.


Asunto(s)
Mariposas Diurnas , Genoma Mitocondrial , Filogenia , Genoma Mitocondrial/genética , Animales , Mariposas Diurnas/genética , Mariposas Diurnas/clasificación , Genómica/métodos , ARN de Transferencia/genética , Evolución Molecular , ARN Ribosómico/genética , Uso de Codones
15.
Lipids Health Dis ; 23(1): 226, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39049120

RESUMEN

BACKGROUND: The impact of exercise dosages based on American College of Sports Medicine(ACSM) recommendations on lipid metabolism in patients after PCI remains unclear. This study conducted a meta-analysis of reported exercise dosages from the literature to address this knowledge gap. METHODS: A comprehensive search of databases was conducted to identify eligible randomized controlled studies of exercise interventions in patients after PCI, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Based on the recommended exercise dosages from ACSM for patients with coronary heart disease, exercise doses in the literature that met the inclusion criteria were categorized into groups that were highly compliant with ACSM recommendations and those with low or uncertain ACSM recommendations. The topic was the effect of exercise dose on lipid metabolism in post-PCI patients. This was assessed using standardized mean difference (SMD) and 95% confidence intervals (95% CI) for changes in triglycerides, total cholesterol, LDL, and HDL. RESULTS: This systematic review included 10 randomized controlled studies. The subgroup analysis revealed statistically significant differences in the high compliance with ACSM recommendations group for triglycerides [SMD=-0.33 (95% CI -0.62, -0.05)], total cholesterol [SMD=-0.55 (95% CI -0.97, -0.13)], low-density lipoprotein [SMD=-0.31 (95% CI -0.49, -0.13)], high-density lipoprotein [SMD = 0.23 (95% CI 0.01, 0.46)], and body mass index [SMD=-0.52 (95% CI -0.87, -0.17)]. Compared to the low or uncertain compliance with ACSM recommendations group, the high compliance group exhibited significant differences in improving TC levels (-0.55(H) vs. -0.46(L)), HDL levels (0.23(H) vs. 0.22(L)), and BMI (-0.52(H) vs. -0.34(L)). CONCLUSIONS: This study supports that high compliance with ACSM-recommended exercise dosages has significant impacts on improving TC levels, HDL levels, and BMI. However, no advantage was observed for TG or LDL levels.


Asunto(s)
Ejercicio Físico , Metabolismo de los Lípidos , Intervención Coronaria Percutánea , Ensayos Clínicos Controlados Aleatorios como Asunto , Triglicéridos , Humanos , Ejercicio Físico/fisiología , Triglicéridos/sangre , Medicina Deportiva , HDL-Colesterol/sangre , Colesterol/sangre , Masculino , LDL-Colesterol/sangre , Terapia por Ejercicio
16.
Appl Environ Microbiol ; 90(7): e0074124, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38953660

RESUMEN

To cope with a high-salinity environment, haloarchaea generally employ the twin-arginine translocation (Tat) pathway to transport secretory proteins across the cytoplasm membrane in a folded state, including Tat-dependent extracellular subtilases (halolysins) capable of autocatalytic activation. Some halolysins, such as SptA of Natrinema gari J7-2, are produced at late-log phase to prevent premature enzyme activation and proteolytic damage of cellular proteins in haloarchaea; however, the regulation mechanism for growth phase-dependent expression of halolysins remains largely unknown. In this study, a DNA-protein pull-down assay was performed to identify the proteins binding to the 5'-flanking sequence of sptA encoding halolysin SptA in strain J7-2, revealing a TrmBL2-like transcription factor (NgTrmBL2). The ΔtrmBL2 mutant of strain J7-2 showed a sharp decrease in the production of SptA, suggesting that NgTrmBL2 positively regulates sptA expression. The purified recombinant NgTrmBL2 mainly existed as a dimer although monomeric and higher-order oligomeric forms were detected by native-PAGE analysis. The results of electrophoretic mobility shift assays (EMSAs) showed that NgTrmBL2 binds to the 5'-flanking sequence of sptA in a non-specific and concentration-dependent manner and exhibits an increased DNA-binding affinity with the increase in KCl concentration. Moreover, we found that a distal cis-regulatory element embedded in the neighboring upstream gene negatively regulates trmBL2 expression and thus participates in the growth phase-dependent biosynthesis of halolysin SptA. IMPORTANCE: Extracellular proteases play important roles in nutrient metabolism, processing of functional proteins, and antagonism of haloarchaea, but no transcription factor involved in regulating the expression of haloaechaeal extracellular protease has been reported yet. Here we report that a TrmBL2-like transcription factor (NgTrmBL2) mediates the growth phase-dependent expression of an extracellular protease, halolysin SptA, of haloarchaeon Natrinema gari J7-2. In contrast to its hyperthermophilic archaeal homologs, which are generally considered to be global transcription repressors, NgTrmBL2 functions as a positive regulator for sptA expression. This study provides new clues about the transcriptional regulation mechanism of extracellular protease in haloarchaea and the functional diversity of archaeal TrmBL2.


Asunto(s)
Halobacteriaceae , Factores de Transcripción , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Halobacteriaceae/genética , Halobacteriaceae/metabolismo , Proteínas Arqueales/genética , Proteínas Arqueales/metabolismo , Regulación de la Expresión Génica Arqueal
17.
J Phys Chem Lett ; 15(28): 7183-7190, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38968427

RESUMEN

Surface-enhanced Raman scattering (SERS) is renowned for amplifying Raman signals, with electromagnetic mechanism (EM) enhancement arising from localized surface plasmon resonances and chemical mechanism (CM) enhancement as a result of charge transfer interactions. Despite the conventional emphasis on EM as a result of plasmonic effects, recent findings highlight the significance of CM when noble metals appear as smaller entities. However, the threshold size of the noble metal clusters/particles corresponding to the switch in SERS mechanisms is not clear at present. In this work, the VSe2-xOx/Au composites with different Au sizes are employed, in which a clear view of the SERS mechanism switch is observed at the Au size range of 16-21 nm. Our findings not only provide insight into the impact of noble metal size on SERS efficiency but also offer quantitative data to assist researchers in making informed judgments when analyzing SERS mechanisms.

19.
Molecules ; 29(13)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38999089

RESUMEN

Spin-gapless semiconductor (SGS), a class of zero-gap materials with fully spin-polarized electrons and holes, offers significant potential for high-speed, low-energy consumption applications in spintronics, electronics, and optoelectronics. Our first-principles calculations revealed that the Pca21 C4N3 monolayer exhibits a ferromagnetic ground state. Its band structure displays SGS-like characteristics, with the energy gap between the valence and conduction bands near the Fermi level in the spin-down channel much smaller than the one in the other spin channel. To enhance its SGS properties, we introduced electrons into the Pca21 C4N3 monolayer by adsorbing the CO gas molecule on its surface. Stable gas adsorption (CO@C4N3) effectively narrowed the band gap in the spin-down channel without changing the band gap in the spin-up channel obviously. Moreover, injecting holes into the CO@C4N3 system could increase the net magnetic moments and induce an SGS-to-metallic phase transition, while injecting electrons into the CO@C4N3 system is able to lower the net magnetic moments and cause an SGS-to-half-metallic phase transition. Our findings not only underscore a new promising material for practical metal-free spintronics applications but also illustrate a viable pathway for designing SGSs.

20.
Blood Press Monit ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38958504

RESUMEN

OBJECTIVES: To determine the independent effect of high-sensitivity C-reactive protein (hs-CRP) and the combined effects of hs-CRP and other traditional risk factors on microalbuminuria in hypertensive patients during the 3-year follow-up period. METHODS AND RESULTS: Baseline hs-CRP levels and other risk factors were measured in 280 adults in 2007. In the third year of examination, 199 patients (mean age 62.5 ±â€…9.5, men 59.3%) were approached for the measurement of microalbuminuria. The subjects were classified into two groups by the median of baseline hs-CRP. Compared to the patients with baseline hs-CRP below the median group (n = 99, 50%), the group with baseline hs-CRP above the median (n = 100, 50%) had higher urinary albumin-to-creatinine ratio (ACR) (P = 0.007) at the end of follow-up period. ACR at the end of follow-up period was significantly correlated with baseline diabetes (ß = 0.342; P < 0.001), baseline SBP (ß = 0.148; P = 0.02), and baseline log-transformed hs-CRP (ß = 0.169; P = 0.01), while adversely correlated with baseline estimated glomerular filtration rate (eGFR) (ß = -0.163; P = 0.02) in multivariate stepwise linear analysis. In addition, ACR change during follow-up period was significantly correlated with baseline diabetes (ß = 0.359; P < 0.001) and baseline log-transformed hs-CRP (ß = 0.190; P = 0.004) in multivariate stepwise linear analysis. The combined effects of baseline hs-CRP and conventional risk factors, such as male sex, diabetes, smoking status, hyperlipidemia, hyperuricemia, and mildly reduced eGFR had a greater risk for microalbuminuria progression. There was no difference in eGFR changes during the follow-up period between two groups. CONCLUSION: Our findings offer a new piece of evidence on the predictive value of baseline hs-CRP for microalbuminuria progression in essential hypertensive patients, and highlight those who combined with traditional cardiovascular risk factors had a greater risk for developing microalbuminuria.

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