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1.
N Engl J Med ; 390(11): 994-1008, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38477987

RESUMEN

BACKGROUND: Persistent hemolytic anemia and a lack of oral treatments are challenges for patients with paroxysmal nocturnal hemoglobinuria who have received anti-C5 therapy or have not received complement inhibitors. Iptacopan, a first-in-class oral factor B inhibitor, has been shown to improve hemoglobin levels in these patients. METHODS: In two phase 3 trials, we assessed iptacopan monotherapy over a 24-week period in patients with hemoglobin levels of less than 10 g per deciliter. In the first, anti-C5-treated patients were randomly assigned to switch to iptacopan or to continue anti-C5 therapy. In the second, single-group trial, patients who had not received complement inhibitors and who had lactate dehydrogenase (LDH) levels more than 1.5 times the upper limit of the normal range received iptacopan. The two primary end points in the first trial were an increase in the hemoglobin level of at least 2 g per deciliter from baseline and a hemoglobin level of at least 12 g per deciliter, each without red-cell transfusion; the primary end point for the second trial was an increase in hemoglobin level of at least 2 g per deciliter from baseline without red-cell transfusion. RESULTS: In the first trial, 51 of the 60 patients who received iptacopan had an increase in the hemoglobin level of at least 2 g per deciliter from baseline, and 42 had a hemoglobin level of at least 12 g per deciliter, each without transfusion; none of the 35 anti-C5-treated patients attained the end-point levels. In the second trial, 31 of 33 patients had an increase in the hemoglobin level of at least 2 g per deciliter from baseline without red-cell transfusion. In the first trial, 59 of the 62 patients who received iptacopan and 14 of the 35 anti-C5-treated patients did not require or receive transfusion; in the second trial, no patients required or received transfusion. Treatment with iptacopan increased hemoglobin levels, reduced fatigue, reduced reticulocyte and bilirubin levels, and resulted in mean LDH levels that were less than 1.5 times the upper limit of the normal range. Headache was the most frequent adverse event with iptacopan. CONCLUSIONS: Iptacopan treatment improved hematologic and clinical outcomes in anti-C5-treated patients with persistent anemia - in whom iptacopan showed superiority to anti-C5 therapy - and in patients who had not received complement inhibitors. (Funded by Novartis; APPLY-PNH ClinicalTrials.gov number, NCT04558918; APPOINT-PNH ClinicalTrials.gov number, NCT04820530.).


Asunto(s)
Anemia Hemolítica , Factor B del Complemento , Inactivadores del Complemento , Hemoglobinas , Hemoglobinuria Paroxística , Humanos , Administración Oral , Anemia Hemolítica/complicaciones , Complemento C5/antagonistas & inhibidores , Factor B del Complemento/antagonistas & inhibidores , Inactivadores del Complemento/administración & dosificación , Inactivadores del Complemento/efectos adversos , Inactivadores del Complemento/uso terapéutico , Transfusión de Eritrocitos , Cefalea/inducido químicamente , Hemoglobinas/análisis , Hemoglobinuria Paroxística/tratamiento farmacológico , Hemoglobinuria Paroxística/etiología , Ensayos Clínicos Fase III como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
J Cell Mol Med ; 28(7): e18237, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38509727

RESUMEN

To explore the underlying molecular mechanisms of supraventricular tachycardia (SVT), this study aimed to analyse the complex relationship between FLRT3 and TGF-ß/SMAD4 signalling pathway, which affects Na+ and K+ channels in cardiomyocytes. Bioinformatics analysis was performed on 85 SVT samples and 15 healthy controls to screen overlapping genes from the key module and differentially expressed genes (DEGs). Expression profiling of overlapping genes, coupled with Receiver Operating Characteristic (ROC) curve analyses, identified FLRT3 as a hub gene. In vitro studies utilizing Ang II-stimulated H9C2 cardiomyocytes were undertaken to elucidate the consequences of FLRT3 silencing on cardiomyocyte apoptosis and autophagic processes. Utilizing a combination of techniques such as quantitative reverse-transcription polymerase chain reaction (qRT-PCR), western blotting (WB), flow cytometry, dual-luciferase reporter assays and chromatin immunoprecipitation polymerase chain reaction (ChIP-PCR) assays were conducted to decipher the intricate interactions between FLRT3, the TGF-ß/SMAD4 signalling cascade and ion channel gene expression. Six genes (AADAC, DSC3, FLRT3, SYT4, PRR9 and SERTM1) demonstrated reduced expression in SVT samples, each possessing significant clinical diagnostic potential. In H9C2 cardiomyocytes, FLRT3 silencing mitigated Ang II-induced apoptosis and modulated autophagy. With increasing TGF-ß concentration, there was a dose-responsive decline in FLRT3 and SCN5A expression, while both KCNIP2 and KCND2 expressions were augmented. Moreover, a direct interaction between FLRT3 and SMAD4 was observed, and inhibition of SMAD4 expression resulted in increased FLRT3 expression. Our results demonstrated that the TGF-ß/SMAD4 signalling pathway plays a critical role by regulating FLRT3 expression, with potential implications for ion channel function in SVT.


Asunto(s)
Apoptosis , Glicoproteínas de Membrana , Proteína Smad4 , Taquicardia Supraventricular , Factor de Crecimiento Transformador beta , Humanos , Apoptosis/genética , Autofagia/genética , Western Blotting , Glicoproteínas de Membrana/metabolismo , Proteína Smad4/metabolismo , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo
3.
Biochem Biophys Res Commun ; 698: 149549, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38266311

RESUMEN

A recently established therapeutic strategy, involving the insertion of biodegradable cog polydioxanone filaments into the quadriceps muscles using the Muscle Enhancement and Support Therapy (MEST) device, has demonstrated significant efficacy in alleviating knee osteoarthritis (OA) pain. This study investigated changes in peripheral sensitization as the potential mechanism underlying MEST-induced pain relief in monoiodoacetate (MIA) induced OA rats. The results revealed that MEST treatment potently reduces MIA-induced sensitization of L3/L4 dorsal root ganglion (DRG) neurons, the primary nociceptor pathway for the knee joint. This reduction in DRG sensitization, as elucidated by voltage-sensitive dye imaging, is accompanied by a diminished overexpression of TRPA1 and NaV1.7, key nociceptor receptors involved in mechanical pain perception. Importantly, these observed alterations strongly correlate with a decrease in mechanically-evoked pain behaviors, providing compelling neurophysiological evidence that MEST treatment alleviates OA pain by suppressing peripheral sensitization.


Asunto(s)
Osteoartritis de la Rodilla , Ratas , Animales , Osteoartritis de la Rodilla/metabolismo , Ratas Sprague-Dawley , Polidioxanona/metabolismo , Músculo Cuádriceps/metabolismo , Dolor/tratamiento farmacológico , Dolor/metabolismo , Modelos Animales de Enfermedad , Ganglios Espinales/metabolismo
4.
BMC Microbiol ; 24(1): 226, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937695

RESUMEN

BACKGROUND: Bacterial antimicrobial resistance poses a severe threat to humanity, necessitating the urgent development of new antibiotics. Recent advances in genome sequencing offer new avenues for antibiotic discovery. Paenibacillus genomes encompass a considerable array of antibiotic biosynthetic gene clusters (BGCs), rendering these species as good candidates for genome-driven novel antibiotic exploration. Nevertheless, BGCs within Paenibacillus genomes have not been extensively studied. RESULTS: We conducted an analysis of 554 Paenibacillus genome sequences, sourced from the National Center for Biotechnology Information database, with a focused investigation involving 89 of these genomes via antiSMASH. Our analysis unearthed a total of 848 BGCs, of which 716 (84.4%) were classified as unknown. From the initial pool of 554 Paenibacillus strains, we selected 26 available in culture collections for an in-depth evaluation. Genomic scrutiny of these selected strains unveiled 255 BGCs, encoding non-ribosomal peptide synthetases, polyketide synthases, and bacteriocins, with 221 (86.7%) classified as unknown. Among these strains, 20 exhibited antimicrobial activity against the gram-positive bacterium Micrococcus luteus, yet only six strains displayed activity against the gram-negative bacterium Escherichia coli. We proceeded to focus on Paenibacillus brasilensis, which featured five new BGCs for further investigation. To facilitate detailed characterization, we constructed a mutant in which a single BGC encoding a novel antibiotic was activated while simultaneously inactivating multiple BGCs using a cytosine base editor (CBE). The novel antibiotic was found to be localized to the cell wall and demonstrated activity against both gram-positive bacteria and fungi. The chemical structure of the new antibiotic was elucidated on the basis of ESIMS, 1D and 2D NMR spectroscopic data. The novel compound, with a molecular weight of 926, was named bracidin. CONCLUSIONS: This study outcome highlights the potential of Paenibacillus species as valuable sources for novel antibiotics. In addition, CBE-mediated dereplication of antibiotics proved to be a rapid and efficient method for characterizing novel antibiotics from Paenibacillus species, suggesting that it will greatly accelerate the genome-based development of new antibiotics.


Asunto(s)
Antibacterianos , Genoma Bacteriano , Familia de Multigenes , Paenibacillus , Paenibacillus/genética , Paenibacillus/metabolismo , Antibacterianos/farmacología , Antibacterianos/biosíntesis , Péptido Sintasas/genética , Sintasas Poliquetidas/genética , Bacteriocinas/genética , Bacteriocinas/farmacología , Bacteriocinas/biosíntesis , Vías Biosintéticas/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Descubrimiento de Drogas/métodos
5.
Am J Hematol ; 99(9): 1768-1777, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38884175

RESUMEN

Crovalimab is a novel C5 complement inhibitor that enables rapid and sustained C5 inhibition with subcutaneous, low-volume self-administration every 4 weeks. COMMODORE 2 (NCT04434092) is a global, randomized, open-label, multicenter, phase 3 trial evaluating the non-inferiority of crovalimab versus eculizumab in patients with paroxysmal nocturnal hemoglobinuria not previously treated with C5 inhibition. C5 inhibitor-naive patients with lactate dehydrogenase (LDH) ≥2 × upper limit of normal (ULN) were randomized 2:1 to crovalimab or eculizumab. Co-primary efficacy endpoints were proportion of patients with hemolysis control (centrally assessed LDH ≤1.5 × ULN) and proportion with transfusion avoidance. Secondary efficacy endpoints were proportions of patients with breakthrough hemolysis, stabilized hemoglobin, and change in FACIT-Fatigue score. The primary treatment period was 24 weeks. Two hundred and four patients were randomized (135 crovalimab; 69 eculizumab). Crovalimab was non-inferior to eculizumab in the co-primary endpoints of hemolysis control (79.3% vs. 79.0%; odds ratio, 1.0 [95% CI, 0.6, 1.8]) and transfusion avoidance (65.7% vs. 68.1%; weighted difference, -2.8 [-15.7, 11.1]), and in the secondary efficacy endpoints of breakthrough hemolysis (10.4% vs. 14.5%; weighted difference, -3.9 [-14.8, 5.3]) and hemoglobin stabilization (63.4% vs. 60.9%; weighted difference, 2.2 [-11.4, 16.3]). A clinically meaningful improvement in FACIT-Fatigue score occurred in both arms. Complete terminal complement activity inhibition was generally maintained with crovalimab. The safety profiles of crovalimab and eculizumab were similar with no meningococcal infections. Most patients who switched from eculizumab to crovalimab after the primary treatment period preferred crovalimab. These data demonstrate the positive benefit-risk profile of crovalimab.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Inactivadores del Complemento , Hemoglobinuria Paroxística , Humanos , Hemoglobinuria Paroxística/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Masculino , Femenino , Persona de Mediana Edad , Adulto , Inactivadores del Complemento/uso terapéutico , Inactivadores del Complemento/efectos adversos , Hemólisis/efectos de los fármacos , Complemento C5/antagonistas & inhibidores , Anciano
6.
Inorg Chem ; 63(17): 7992-8000, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38627375

RESUMEN

The electrochemical reduction of carbon dioxide (CO2) to produce fuels and chemicals has garnered significant attention. However, achieving control over the selectivity of the resulting products remains a challenging task, particularly within molecular systems. In this study, we employed a molecular silver complex immobilized on graphitized mesoporous carbon (GMC) as a catalyst for converting CO2 into CO, achieving an impressive selectivity of over 90% at -1.05 V vs RHE. Notably, the newly formed silver nanoparticles emerged as the active sites responsible for this high CO selectivity rather than the molecular system. Intriguingly, the introduction of copper ions into the restructured Ag-nanoparticle-decorated carbon altered the product selectivity. At -1.1 V vs RHE in 0.1 M KCl, we achieved a high C2 selectivity of 75%. Furthermore, not only the Ag-Cu bimetallic nanoparticle but also the small-sized Ag-Cu nanocluster decorated over GMC was proposed as active sites during catalytic reactions. Our straightforward approach offers valuable insights for fine-tuning the product selectivity of immobilized molecular systems, extending beyond C1 products.

7.
Transpl Infect Dis ; 26(4): e14328, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38980949

RESUMEN

INTRODUCTION: Cytomegalovirus (CMV) infection is a major cause of transplantation-related morbidity and mortality. This study assessed the utility of the QuantiFERON monitor (QFM; Qiagen) for the prediction of early CMV infection and viral burden. METHODS: QuantiFERON-CMV (QF-CMV; Qiagen) and QFM were measured at the post-allogeneic hematopoietic stem cell transplantation (HSCT) week 4. CMV DNA was measured at every visit until post-HSCT week 24. The QFM cutoff specific to CMV infection was established. RESULT: At the post-HSCT week 4, the QFM cutoff predicting CMV infection was 86.95 IU/mL. While QF-CMV results at the post-HSCT week 4 were associated with high-level CMV infection (CMV DNA ≥ 5,000 IU/mL) but not with CMV infection (CMV DNA ≥ 500 IU/mL), QFM was associated with both CMV infection and high-level CMV infection. Both indeterminate QF-CMV and nonreactive QFM were associated with increased peak CMV DNA. CONCLUSION: Low QFM is a risk factor for CMV infection and increased CMV viral loads. QFM at post-HSCT week 4 can be utilized as an assay to predict the risk and burden of early CMV infection in HSCT recipients, in conjunction with other risk factors.


Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , ADN Viral , Trasplante de Células Madre Hematopoyéticas , Trasplante Homólogo , Carga Viral , Humanos , Infecciones por Citomegalovirus/diagnóstico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Citomegalovirus/aislamiento & purificación , Citomegalovirus/inmunología , ADN Viral/sangre , Trasplante Homólogo/efectos adversos , Adulto Joven , Anciano , Factores de Riesgo , Adolescente
8.
Artículo en Inglés | MEDLINE | ID: mdl-38982331

RESUMEN

In this paper, we describe our discovery of burnettiene A (1) as an anti-malarial compound from the culture broth of Lecanicillium primulinum (Current name: Flavocillium primulinum) FKI-6715 strain utilizing our original multidrug-sensitive yeast system. This polyene-decalin polyketide natural product was originally isolated as an anti-fungal active compound from Aspergillus burnettii. However, the anti-fungal activity of 1 has been revealed in only one fungal species for and the mechanism of action of 1 remains unknown. After the validation of mitochondrial function inhibitory of 1, we envisioned a new anti-malarial drug discovery platform based on mitochondrial function inhibitory activity. We evaluated anti-malarial activity and 1 showed anti-malarial activity against Plasmodium falciparum FCR3 (chloroquine sensitive) and K1 strain (chloroquine resistant). Our study revealed the utility of our original screening system based on a multidrug-sensitive yeast and mitochondrial function inhibitory activity for the discovery of new anti-malarial drug candidates.

9.
J Korean Med Sci ; 39(8): e81, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38442722

RESUMEN

BACKGROUND: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematologic disorder caused by uncontrolled terminal complement activation, which leads to intravascular hemolysis (IVH), thromboembolism (TE), renal failure, and premature mortality. METHODS: We performed a secondary analysis of data collected from patients enrolled in the Korean National PNH Registry to assess the relative importance of risk factors, specifically lactate dehydrogenase (LDH) and hemoglobin (Hb), in predicting the incidence of TE, impaired renal function, and death in complement inhibitor-naïve patients with PNH. RESULTS: Multivariate regression modeling indicated that LDH ≥ 1.5 × upper limit of normal (ULN), male sex, and pain were associated with increased risk of TE (P = 0.016, 0.045, and 0.033, respectively), hemoglobinuria and pain were associated with an increased risk of impaired renal function (P = 0.034 and 0.022, respectively), and TE was associated with an increased incidence of death (P < 0.001). Hb < 8 g/dL was not a predictor of TE, impaired renal function, or death in multivariate regression analyses. Standardized mortality ratio analysis indicated that LDH ≥ 1.5 × ULN (P < 0.001), Hb < 8 g/dL (P < 0.001), and Hb ≥ 8 g/dL (P = 0.004) were all risk factors for death; in contrast, patients with LDH < 1.5 × ULN had similar mortality to the general population. CONCLUSION: In complement inhibitor-naïve patients with PNH, LDH ≥ 1.5 × ULN was a significant predictor of TE, and TE was a significant predictor of death. Hb was not a significant predictor of TE, impaired renal function, or death. Therefore, controlling IVH will improve clinical outcomes for patients with PNH.


Asunto(s)
Hemoglobinuria Paroxística , Tromboembolia , Humanos , Masculino , Hemoglobinuria Paroxística/complicaciones , Hemoglobinuria Paroxística/diagnóstico , Inactivadores del Complemento , L-Lactato Deshidrogenasa , Dolor , República de Corea
10.
Int J Mol Sci ; 25(6)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38542065

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) has emerged as a significant liver ailment attributed to factors like obesity and diabetes. While ongoing research explores treatments for NAFLD, further investigation is imperative to address this escalating health concern. NAFLD manifests as hepatic steatosis, precipitating insulin resistance and metabolic syndrome. This study aims to validate the regenerative potential of chimeric fibroblast growth factor 21 (FGF21) and Hepatocyte Growth Factor Receptor (HGFR) in NAFLD-afflicted liver cells. AML12, a murine hepatocyte cell line, was utilized to gauge the regenerative effects of chimeric FGF21/HGFR expression. Polysaccharide accumulation was affirmed through Periodic acid-Schiff (PAS) staining, while LDL uptake was microscopically observed with labeled LDL. The expression of FGF21/HGFR and NAFLD markers was analyzed by mRNA analysis with RT-PCR, which showed a decreased expression in acetyl-CoA carboxylase 1 (ACC1) and sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP) with increased expression of hepatocellular growth factor (HGF), hepatocellular nuclear factor 4 alpha (HNF4A), and albumin (ALB). These findings affirm the hepato-regenerative properties of chimeric FGF21/HGFR within AML12 cells, opening novel avenues for therapeutic exploration in NAFLD.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Animales , Ratones , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Hígado/metabolismo , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/metabolismo
11.
Int J Mol Sci ; 25(1)2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38203555

RESUMEN

Sepsis is a systemic inflammatory syndrome that results in multiple-organ failure caused by a dysregulated host immune response to microbial infection. Astragali complanati semen extract (ACSE) exhibits pharmacological activities, including antioxidant, anticancer, antiaging, and anti-diabetes effects. It is widely used in traditional medicine to treat liver and kidney diseases; however, the protective effect of ACSE on sepsis and its mechanisms are unknown. In the present study, we investigated the anti-inflammatory effects and potential mechanisms of the action of ACSE on sepsis. We show that ACSE improved survival rates in mouse models of acute sepsis induced by CLP (cecal ligation and puncture) and LPS stimulation. ACSE administration decreased aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in sepsis-induced mice. Furthermore, ACSE reduced the levels of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) in the serum of septic mice. ACSE treatment inhibited the expression of these proinflammatory genes in LPS-stimulated J774 macrophages. Moreover, ACSE inhibited the phosphorylation of the IκB kinase (IKK) and the nuclear translocation of p65 NF-κB by LPS stimulation in macrophages. These results reveal the mechanism underlying the protective effect of ACSE against sepsis by inhibiting NF-κB activation and suggest that ACSE could be a potential therapeutic candidate to treat acute inflammatory diseases.


Asunto(s)
Planta del Astrágalo , Sepsis , Choque Séptico , Animales , Ratones , Lipopolisacáridos/toxicidad , FN-kappa B , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Etanol , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico
12.
J Imaging Inform Med ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103566

RESUMEN

Medical staff inspect lumbar X-ray images to diagnose lumbar spine diseases, and the analysis process is currently automated using deep-learning techniques. The detection of landmarks is necessary in the automatic process of localizing the position and identifying the morphological features of the vertebrae. However, detection errors may occur owing to the noise and ambiguity of images, as well as individual variations in the shape of the lumbar vertebrae. This study proposes a method to improve the robustness of landmark detection results. This method assumes that landmarks are detected by a convolutional neural network-based two-step model consisting of Pose-Net and M-Net. The model generates a heatmap response to indicate the probable landmark positions. The proposed method then corrects the landmark positions using the heatmap response and active shape model, which employs statistical information on the landmark distribution. Experiments were conducted using 3600 lumbar X-ray images, and the results showed that the landmark detection error was reduced by the proposed method. The average value of maximum errors decreased by 5.58% after applying the proposed method, which combines the outstanding image analysis capabilities of deep learning with statistical shape constraints on landmark distribution. The proposed method could also be easily integrated with other techniques to increase the robustness of landmark detection results such as CoordConv layers and non-directional part affinity field. This resulted in a further enhancement in the landmark detection performance. These advantages can improve the reliability of automatic systems used to inspect lumbar X-ray images. This will benefit both patients and medical staff by reducing medical expenses and increasing diagnostic efficiency.

13.
Chemosphere ; 352: 141458, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38364920

RESUMEN

Accurate analyses of total organic carbon (TOC) encompassing particulate organic carbon in wastewater are key for evaluating the behavior of particulate organic contaminants and maintaining the carbon mass balance throughout the wastewater treatment process. This study was conducted to develop candidate reference materials of environmental origin from excess sludge collected from wastewater treatment facilities, primarily receiving industrial wastewater and livestock manure as the main sources. Homogeneity and stability assessments for total carbon (TC) and TOC were conducted in the particle samples following the standardized procedures of ISO Guide 35 and ISO 13258. The results showed that high inorganic carbon (IC) content in particles, such as YJ(500) (IC: 29%), rendered them unsuitable for TOC quality control (QC), as they increased uncertainty in both homogeneity and stability assessments. Additionally, a13C NMR analysis revealed that samples with a high (O-alkyl)/(C-H-alkyl) ratio in their carbon structures exhibited relatively low stability. Through the homogeneity and stability assessments, a particle sample, YJ(100), was selected as the reference material (RM); the assigned values were as follows: 30.78% for TC and 27.94% for TOC, with uncertainties of 0.01% and 1.1%, respectively. Furthermore, considering sample transportation conditions, the safe storage period for the RM particles was determined to be 2 weeks under harsh conditions (at 40 °C). In our inter-laboratory test (n = 8) using the particle samples, we confirmed that the particle samples can effectively enhance particle processing QC and validate a proposed suspended solids pretreatment method. This study showcases valuable environmental particle sample production and evaluation, offering potential advancements in the QC of TOC analysis for wastewater samples.


Asunto(s)
Aguas del Alcantarillado , Aguas Residuales , Aguas del Alcantarillado/química , Carbono/análisis , Polvo
14.
Regen Biomater ; 11: rbae077, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974667

RESUMEN

Quadriceps muscles play a pivotal role in knee osteoarthritis (OA) progression and symptom manifestation, particularly pain. This research investigates the therapeutic effectiveness of muscle enhancement and support therapy (MEST), a recently developed device intended for intramuscular insertion of cog polydioxanone filaments, in quadriceps restoration to alleviate OA pain. Knee OA was induced in Sprague Dawley rats via monoiodoacetate injections. MEST or sham treatment was performed in OA or Naive rat quadriceps. Pain was assessed using paw withdrawal threshold and weight bearing. Quadriceps injury and recovery via MEST were evaluated using biomarkers, tissue morphology, muscle mass, contractile force and hindlimb torque. Satellite cell and macrophage activation, along with their activators, were also assessed. Data were compared at 1- and 3-weeks post-MEST treatment (M-W1 and M-W3). MEST treatment in OA rats caused muscle injury, indicated by elevated serum aspartate transferase and creatinine kinase levels, and local ß-actin changes at M-W1. This injury triggered pro-inflammatory macrophage and satellite cell activation, accompanied by heightened interleukin-6 and insulin-like growth factor-1 levels. However, by M-W3, these processes gradually shifted toward inflammation resolution and muscle restoration. This was seen in anti-inflammatory macrophage phenotypes, sustained satellite cell activation and injury markers regressing to baseline. Quadriceps recovery in mass and strength from atrophy correlated with substantial OA pain reduction at M-W3. This study suggests that MEST-induced minor muscle injury triggers macrophage and satellite cell activation, leading to recovery of atrophied quadriceps and pain relief in OA rats.

15.
Protein Sci ; 33(7): e5067, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38864716

RESUMEN

The N-degron pathway determines the half-life of proteins by selectively destabilizing the proteins bearing N-degrons. N-terminal glutamine amidohydrolase 1 (NTAQ1) plays an essential role in the arginine N-degron (Arg/N-degron) pathway as an initializing enzyme via the deamidation of the N-terminal (Nt) glutamine (Gln). However, the Nt-serine-bound conformation of hNTAQ1 according to the previously identified crystal structure suggests the possibility of other factors influencing the recognition of Nt residues by hNTAQ1. Hence, in the current study, we aimed to further elucidate the substrate recognition of hNTAQ1; specifically, we explored 12 different substrate-binding conformations of hNTAQ1 depending on the subsequent residue of Nt-Gln. Results revealed that hNTAQ1 primarily interacts with the protein Nt backbone, instead of the side chain, for substrate recognition. Here, we report that the Nt backbone of proteins appears to be a key component of hNTAQ1 function and is the main determinant of substrate recognition. Moreover, not all second residues from Nt-Gln, but rather distinctive and charged residues, appeared to aid in detecting substrate recognition. These new findings define the substrate-recognition process of hNTAQ1 and emphasize the importance of the subsequent Gln residue in the Nt-Gln degradation system. Our extensive structural and biochemical analyses provide insights into the substrate specificity of the N-degron pathway and shed light on the mechanism underlying hNTAQ1 substrate recognition. An improved understanding of the protein degradation machinery could aid in developing therapies to promote overall health through enhanced protein regulation, such as targeted protein therapies.


Asunto(s)
Arginina , Humanos , Especificidad por Sustrato , Arginina/química , Arginina/metabolismo , Modelos Moleculares , Glutamina/metabolismo , Glutamina/química , Amidohidrolasas/química , Amidohidrolasas/metabolismo , Amidohidrolasas/genética , Conformación Proteica , Proteolisis , Degrones
16.
Pharmacol Rep ; 76(2): 368-378, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38498259

RESUMEN

BACKGROUND: Excessive stress, a major problem in modern societies, affects people of all ages worldwide. Corticosterone is one of the most abundant hormones secreted during stressful conditions and is associated with various dysfunctions in the body. In particular, we aimed to investigate the protective effects of hygrolansamycin C (HYGC) against corticosterone-induced cellular stress, a manifestation of excessive stress prevalent in contemporary societies. METHODS: We isolated HYGC from Streptomyces sp. KCB17JA11 and subjected PC12 cells to corticosterone-induced stress. The effects of HYGC were assessed by measuring autophagy and the expression of mitogen-activated protein kinase (MAPK) phosphorylation-related genes. We used established cellular and molecular techniques to analyze protein levels and pathways. RESULTS: HYGC effectively protected cells against corticosterone-induced injury. Specifically, it significantly reduced corticosterone-induced oxidative stress and inhibited the expression of autophagy-related proteins induced by corticosterone, which provided mechanistic insight into the protective effects of HYGC. At the signaling level, HYGC suppressed c-Jun N-terminal kinase and extracellular signal-regulated kinase phosphorylation and p38 activation. CONCLUSIONS: HYGC is a promising candidate to counteract corticosterone-induced apoptosis and oxidative stress. Autophagy and MAPK pathway inhibition contribute to the protective effects of HYGC. Our findings highlight the potential of HYGC as a therapeutic agent for stress-related disorders and serve as a stepping stone for further exploration and development of stress management strategies.


Asunto(s)
Corticosterona , Proteínas Quinasas p38 Activadas por Mitógenos , Ratas , Animales , Humanos , Corticosterona/toxicidad , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Sistema de Señalización de MAP Quinasas , Estrés Oxidativo , Transducción de Señal , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Apoptosis , Autofagia
17.
Bioresour Technol ; 403: 130848, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38761868

RESUMEN

This study addresses membrane biofouling in membrane bioreactors (MBRs) by exploring fungal-to-bacterial quorum quenching (QQ) strategies. While most research has been focused on bacterial-to-bacterial QQ tactics, this study identified fungal strain Vanrija sp. MS1, which is capable of degrading N-acyl-homoserine lactones (signaling molecules of Gram-negative bacteria). To determine the benefits of fungal over bacterial strains, after immobilization on fluidizing spherical beads in an MBR, MS1 significantly reduced the fouling rate by 1.8-fold compared to control MBR, decreased extracellular polymeric substance levels in the biofilm during MBR operation, and favorably changed microbial community and bacterial network, resulting in biofouling mitigation. It is noteworthy that, unlike Rhodococcus sp. BH4, MS1 enhanced QQ activity when switching from neutral to acidic conditions. These results suggest that MS1 has the potential for the effective treatment of acidic industrial wastewater sources such as semiconductor and secondary battery wastewater using MBRs.


Asunto(s)
Incrustaciones Biológicas , Reactores Biológicos , Membranas Artificiales , Percepción de Quorum , Aguas Residuales , Purificación del Agua , Incrustaciones Biológicas/prevención & control , Reactores Biológicos/microbiología , Aguas Residuales/química , Aguas Residuales/microbiología , Purificación del Agua/métodos , Biopelículas , Bacterias/metabolismo
18.
Int J Nanomedicine ; 19: 8403-8415, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39165772

RESUMEN

Aim: Cyperus rotundus L. (CR) is traditionally used in medicine for its anti-inflammatory properties. In particular, α-cyperone, which is isolated from the essential oil and found primarily in the n-hexane fraction of the ethanolic extract, is known to inhibit NO production in LPS-stimulated RAW 264.7 cells. However, high concentrations of α-cyperone are required for sufficient anti-inflammatory activity. Even, essential oil obtained from C. rotundus has the disadvantage of low solubility and stability in aqueous environment, which makes it difficult to be applied in various fields and easily loses its activity. Therefore, in this study, we aimed to increase the extraction yield of C. rotundus by microbubble extraction and prepare nanoparticles (NPs) that can preserve its activity in a stable and bioavailable manner by utilizing nanoprecipitation. Methods: C. rotundus rhizomes were extracted in 50% ethanol using microbubbles and then fractionated with n-hexane to obtain α-cyperone-rich C. rotundus n-hexane fraction (CRHF). The biodegradable plant extract, α-cyperone, was prepared as green nanoparticles (CR@NPs) by nanoprecipitation technique under mild reaction conditions. The physicochemical properties of CR@NPs, including size, polydispersity index, and surface charge, were determined using dynamic light scattering. The extraction yield and encapsulation efficiency of α-cyperone were quantified by high-performance liquid chromatography. Antioxidant and anti-inflammatory activities were evaluated by DPPH assay and in vitro ROS and NO assays, and biocompatibility was assessed by MTT assay. Results: C. rotundus loaded nanoparticles demonstrated overcoming the limitation of α-cyperone solubility and stability in CRHF and also the antioxidant, anti-inflammatory properties as evidenced by in vitro assays in cellular models. Conclusion: The versatility of green chemistry, such as α-cyperone, enables the production of nanoparticles with promising biomedical applications such as cosmetics, pharmaceuticals, and food products.


Asunto(s)
Antiinflamatorios , Antioxidantes , Cyperus , Hexanos , Nanopartículas , Extractos Vegetales , Ratones , Cyperus/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antiinflamatorios/farmacología , Antiinflamatorios/química , Células RAW 264.7 , Animales , Antioxidantes/farmacología , Antioxidantes/química , Hexanos/química , Nanopartículas/química , Óxido Nítrico , Supervivencia Celular/efectos de los fármacos , Tamaño de la Partícula
19.
ACS Appl Mater Interfaces ; 16(13): 16328-16339, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38516946

RESUMEN

Kesterite-based Cu2ZnSn(S,Se)4 (CZTSSe) thin-film solar cells (TFSCs) are a promising candidate for low-cost, clean energy production owing to their environmental friendliness and the earth-abundant nature of their constituents. However, the advancement of kesterite TFSCs has been impeded by abundant defects and poor microstructure, limiting their performance potential. In this study, we present efficient Ag-alloyed CZTSSe TFSCs enabled by a facile metallic precursor engineering approach. The positioning of the Ag nanolayer in the metallic stacked precursor proves crucial in expediting the formation of Cu-Sn metal alloys during the alloying process. Specifically, Ag-included metallic precursors promote the growth of larger grains and a denser microstructure in CZTSSe thin films compared to those without Ag. Moreover, the improved uniformity of Ag, facilitated by the evaporation deposition technique, significantly suppresses the formation of detrimental defects and related defect clusters. This suppression effectively reduces nonradiative recombination, resulting in enhanced performance in kesterite TFSCs. This study not only introduces a metallic precursor engineering strategy for efficient kesterite-based TFSCs but also accelerates the development of microstructure evolution from metallic stacked precursors to metal chalcogenide compounds.

20.
Adv Sci (Weinh) ; 11(15): e2305938, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38342621

RESUMEN

Kesterite is an earth-abundant energy material with high predicted power conversion efficiency, making it a sustainable and promising option for photovoltaics. However, a large open circuit voltage Voc deficit due to non-radiative recombination at intrinsic defects remains a major hurdle, limiting device performance. Incorporating Ge into the kesterite structure emerges as an effective approach for enhancing performance by manipulating defects and morphology. Herein, how different amounts of Ge affect the kesterite growth pathways through the combination of advanced microscopy characterization techniques are systematically investigated. The results demonstrate the significance of incorporating Ge during the selenization process of the CZTSSe thin film. At high temperature, the Ge incorporation effectively delays the selenization process due to the formation of a ZnSe layer on top of the metal alloys through decomposition of the Cu-Zn alloy and formation of Cu-Sn alloy, subsequently forming of Cu-Sn-Se phase. Such an effect is compounded by more Ge incorporation that further postpones kesterite formation. Furthermore, introducing Ge mitigates detrimental "horizontal" grain boundaries by increasing the grain size on upper layer. The Ge incorporation strategy discussed in this study holds great promise for improving device performance and grain quality in CZTSSe and other polycrystalline chalcogenide solar cells.

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