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1.
J Phys Chem A ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656182

RESUMEN

It is of great importance to understand the intrinsic relationship between phototautomerization and photoelectric properties for the exploration of novel organic materials. Here, in order to chemically control the protonation process, the aminated isoxazole derivative (2,2'-(isoxazolo[5,4-d]isoxazole-3,6-diyl)dibenzenaminium, DP-DA-DPIxz) with -N═ as the proton acceptor was designed to achieve the twisted intramolecular charge transfer (TICT) state which was triggered by an excited-state intramolecular proton transfer (ESIPT) process. This kind of protonation enhanced the intramolecular hydrogen bonding, conjugative effect, and steric hindrance effects, ensuring a barrierless spontaneous TICT process. Through the intramolecular proton transfer, the configuration torsion and conjugation dissociation of the DP-DA-DPIxz molecule was favored, which led to efficient charge separation and remarkable variations in light-emitting properties. We hope the present investigation will provide a new approach to design novel optoelectronic organic materials and shine light on the understanding of the charge transfer and separation process in molecular science.

2.
Infect Agent Cancer ; 19(1): 17, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664813

RESUMEN

BACKGROUND: Hepatitis C patients with advanced fibrosis or cirrhosis are at high risk of developing hepatocellular carcinoma (HCC), even after sustained virological response (SVR). Clinical recommendations impose a significant burden on patients by recommending lifelong screening for HCC every six months. The goals of this study were to develop a nomogram that accurately stratifies risk of HCC and improve the screening approach that is currently in use. METHOD: Risk factors for HCC were identified using univariate and multivariate analyses in this prospective study. We developed and validated a nomogram for assessing hepatocellular carcinoma risk after SVR in patients with advanced fibrosis and cirrhosis. RESULTS: During the median follow-up period of 61.00 (57.00-66.00) months in the derivation cohort, 37 patients (9.61%) developed HCC. Older age (HR = 1.08, 95% CI 1.02-1.14, p = 0.009), male gender (HR = 2.38, 95% CI 1.10-5.13, p = 0.027), low serum albumin levels (HR = 0.92, 95% CI 0.86-1.00, p = 0.037), and high liver stiffness measurement (LSM) (HR = 1.03, 95% CI 1.01-1.06, p = 0.001) were found to be independent predictors of HCC development. Harrell's C-index for the derivation cohort was 0.81. The nomogram's 3-, 5- and 7-years time-dependent AUROCSs were 0.84 (95% CI 0.80-0.88), 0.83 (95% CI 0.79-0.87), and 0.81 (95% CI 0.77-0.85), respectively (all p > 0.05). According to the nomogram, patients are categorized as having low, intermediate, or high risk. The annual incidence rates of HCC in the three groups were 0.18%, 1.29%, and 4.45%, respectively (all p < 0.05). CONCLUSIONS: Older age, male gender, low serum albumin levels, and high LSM were risk factors for HCC after SVR in hepatitis C patients with advanced fibrosis and cirrhosis. We used these risk factors to establish a nomogram. The nomogram can identify a suitable screening plan by classifying hepatitis C patients according to their risk of HCC.

3.
Int J Biol Macromol ; 267(Pt 2): 131429, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38583828

RESUMEN

Herein, a novel chitosan Schiff base (CS-FGA) as a sustainable corrosion inhibitor has been successfully synthesized via a simple amidation reaction by using an imidazolium zwitterion and chitosan (CS). The corrosion inhibition property of CS-FGA for mild steel (MS) in a 1.0 M HCl solution was studied by various electrochemical tests and physical characterization methods. The findings indicate that the maximum inhibition efficiency of CS-FGA as a mixed-type inhibitor for MS in 1.0 M HCl solution with 400 mg L-1 reaches 97.6 %, much much higher than the CS and the recently reported chitosan-based inhibitors. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and water contact angle (WCA) results reveal that the CS-FGA molecules firmly adsorb on the MS surface to form a protective layer. The adsorption of CS-FGA on the MS surface belongs to the Langmuir adsorption isotherm containing both the physisorption and chemisorption. According to the X-ray photoelectron spectroscopy (XPS) and UV-vis spectrum, FeN bonds presented on the MS surface further prove the chemisorption between CS-FGA and Fe to generate the stable protective layer. Additionally, theoretical calculations from quantum chemical calculation (DFT) and molecular simulations (MD) were performed to reveal the inhibition mechanism of CS-FGA.

4.
Mycopathologia ; 189(3): 35, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637433

RESUMEN

Candida auris, an emerging and multidrug-resistant fungal pathogen, has led to numerous outbreaks in China. While the resistance mechanisms against azole and amphotericin B have been studied, the development of drug resistance in this pathogen remains poorly understood, particularly in in vivo-generated drug-resistant strains. This study employed pathogen whole-genome sequencing to investigate the epidemiology and drug-resistance mutations of C. auris using 16 strains isolated from two patients. Identification was conducted through Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and antimicrobial susceptibilities were assessed using broth microdilution and Sensititre YeastOne YO10. Whole-genome sequencing revealed that all isolates belonged to the South Asian lineage, displaying genetic heterogeneity. Despite low genetic variability among patient isolates, notable mutations were identified, including Y132F in ERG11 and A585S in TAC1b, likely linked to increased fluconazole resistance. Strains from patient B also carried F214L in TAC1b, resulting in a consistent voriconazole minimum inhibitory concentration of 4 µg/mL across all isolates. Furthermore, a novel frameshift mutation in the SNG1 gene was observed in amphotericin B-resistant isolates compared to susceptible ones. Our findings suggest the potential transmission of C. auris and emphasize the need to explore variations related to antifungal resistance. This involves analyzing genomic mutations and karyotypes, especially in vivo, to compare sensitive and resistant strains. Further monitoring and validation efforts are crucial for a comprehensive understanding of the mechanisms of drug resistance in C. auris.


Asunto(s)
Antifúngicos , Candidiasis , Humanos , Antifúngicos/farmacología , Candidiasis/microbiología , Candida auris , Candida , Anfotericina B/farmacología , Farmacorresistencia Fúngica/genética , Pruebas de Sensibilidad Microbiana
5.
Artículo en Inglés | MEDLINE | ID: mdl-38656852

RESUMEN

IoT and 5G-enabled smart healthcare allow medical practitioners to diagnose patients from any location. Patients can share their electronic health records (EHRs) along with body data collected by wireless body area network (WBAN) devices with the cloud server. Private information, including medical practitioners' identities and patients' EHRs, is susceptible to leakage from the hospital or cloud servers. Medical practitioners' secret keys must be promptly revoked after diagnosis. In response to the challenges associated with user authentication and secret key revocation, this paper proposes an access control scheme with privacy-preserving authentication and flexible revocation for smart healthcare using attribute-based encryption (ABE), named PAFR-ABE, which provides access control to prevent malicious users from decrypting EHRs. Meanwhile, PAFR-ABE ensures privacy-preserving authentication for users during secret key generation, safeguarding users' identities and preventing unauthorized requests for secret keys. In addition, PAFR-ABE achieves flexible revocation and recovery of secret keys, eliminating the need to update secret keys for unrevoked users. Security analysis indicates that PAFR-ABE meets the security requirements of an access control scheme for smart healthcare, especially in terms of forward security and backward security. Performance analysis demonstrates that PAFR-ABE reduces key generation time by 57% and revocation time by thousands of times, compared with typical access control schemes.

6.
Langmuir ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38651309

RESUMEN

Corrosion protection of metal has become an important and urgent topic, which requires the development of an inexpensive, environmentally friendly, and highly efficient corrosion inhibitor. Herein, a sweet potato leaf extract (SPL) was obtained by a simple water-based extraction method and then as a green corrosion inhibitor for 6N01 Al alloy in the seawater was well investigated by the weight loss method and various electrochemical tests. Fourier transform infrared (FT-IR) and ultraviolet-visible (UV-vis) spectroscopies were carried out to investigate the compositions of SPL. The findings from the potentiodynamic polarization (PDP) curves suggest that SPL functions as a typical mixed-type corrosion inhibitor. Notably, the maximum corrosion inhibition efficiency reaches 94.6% following a 36 h immersion period at 25 °C. The adsorption behavior of SPL on the Al alloy surface belongs to the Langmuir adsorption isotherm. The Gibbs free energy value illustrates that the adsorption of SPL contains both physisorption and chemisorption. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) indicate that SPL is firmly attached to the Al alloy surface by making a protective layer, which can effectively inhibit the corrosion of the Al alloy in the seawater. Furthermore, quantum chemical calculations were applied to validate the chemical adsorption and elucidate the relationship between the electronic structure of the active components in SPL and their effectiveness in corrosion inhibition.

7.
Curr Osteoporos Rep ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38652430

RESUMEN

PURPOSE OF REVIEW: This review aims to provide a theoretical basis and insights for quercetin's clinical application in the prevention and treatment of osteoporosis (OP), analyzing its roles in bone formation promotion, bone resorption inhibition, anti-inflammation, antioxidant effects, and potential mechanisms. RECENT FINDINGS: OP, a prevalent bone disorder, is marked by reduced bone mineral density and impaired bone architecture, elevating the risk of fractures in patients. The primary approach to OP management is pharmacotherapy, with quercetin, a phytochemical compound, emerging as a focus of recent interest. This natural flavonoid exerts regulatory effects on bone marrow mesenchymal stem cells, osteoblasts, and osteoclasts and promotes bone health and metabolic equilibrium via anti-inflammatory and antioxidative pathways. Although quercetin has demonstrated significant potential in regulating bone metabolism, there is a need for further high-quality clinical studies focused on medicinal quercetin.

8.
Animals (Basel) ; 14(7)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38612311

RESUMEN

Duck egg production, like that of laying hens, follows a typical low-peak-low cycle, reflecting the dynamics of the reproductive system. Post-peak, some ducks undergo a cessation of egg laying, indicative of a regression process in the oviduct. Notably, the magnum, being the longest segment of the oviduct, plays a crucial role in protein secretion. Despite its significance, few studies have investigated the molecular mechanisms underlying oviduct regression in ducks that have ceased laying eggs. In this study, we conducted single-cell transcriptome sequencing on the magnum tissue of Shaoxing ducks at 467 days of age, utilizing the 10× Genomics platform. This approach allowed us to generate a detailed magnum transcriptome map of both egg-laying and ceased-laying ducks. We collected transcriptome data from 13,708 individual cells, which were then subjected to computational analysis, resulting in the identification of 27 distinct cell clusters. Marker genes were subsequently employed to categorize these clusters into specific cell types. Our analysis revealed notable heterogeneity in magnum cells between the egg-laying and ceased-laying ducks, primarily characterized by variations in cells involved in protein secretion and extracellular matrix (ECM)-producing fibroblasts. Specifically, cells engaged in protein secretion were predominantly observed in the egg-laying ducks, indicative of their role in functional albumen deposition within the magnum, a phenomenon not observed in the ceased-laying ducks. Moreover, the proportion of THY1+ cells within the ECM-producing fibroblasts was found to be significantly higher in the egg-laying ducks (59%) compared to the ceased-laying ducks (24%). Similarly, TIMP4+ fibroblasts constituted a greater proportion of the ECM-producing fibroblasts in the egg-laying ducks (83%) compared to the ceased-laying ducks (58%). These findings suggest a potential correlation between the expression of THY1 and TIMP4 in ECM-producing fibroblasts and oviduct activity during functional reproduction. Our study provides valuable single-cell insights that warrant further investigation into the biological implications of fibroblast subsets in the degeneration of the reproductive tract. Moreover, these insights hold promise for enhancing the production efficiency of laying ducks.

9.
BMC Ophthalmol ; 24(1): 175, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627709

RESUMEN

PURPOSE: The purpose of this study was to compare the preoperative anxiety, aqueous humor monocyte chemoattractant protein-1 (MCP-1) concentration, intraoperative pain, and degree of cooperation of the first eye implantable collamer lens (ICL) surgery with the second eye surgery, of the 1-day interval group with the 1-week interval group, and to investigate the possible causes of these differences, as well as to determine the appropriate interval between bilateral eye ICL surgeries. METHOD: The study was a prospective observational study. A total of 120 patients who underwent bilateral ICL surgery at the Department of Ophthalmology, West China Fourth Hospital, Sichuan University, from July to September 2023, were enrolled. The patients were divided into a 1-day interval group and a 1-week interval group. The ICL surgery was performed on both eyes according to the schedule. Anxiety levels, aqueous humor MCP1, cooperativeness, surgical time, pain and satisfaction, and patients' estimations of the time spent in the operation were recorded for each eye. The patients were instructed to recall the intraoperative pain of the first eye surgery after the operation of the second eye. Statistical analyses (two independent samples t-test,two paired samples t-test, the rank-sum test, the chi-square test, non-parametric test with multiple independent samples) were performed to compare the differences between each score in both eyes and two groups. Furthermore, we examined the relationship between pain levels and the reproductive history of the patients. RESULTS: In the 1-day interval group, male/female is 22/52, average age is 25.24±5.00. In the 1-week interval group, male/female is 17/29, average age is 25.39±5.57. There was no statistically significant difference between the two groups. In both groups, patients were less nervous, had significantly more pain, had less surgical satisfaction, had a longer estimated operative time, and had elevated preoperative MCP1 during the second eye operation. In the second eye surgery, the patient's cooperation worsened, but it did not lead to an increase in surgical time. A significant proportion of patients, particularly in the 1-week interval group, recalled experiencing reduced pain during the first eye surgery. The 1-week interval group had a higher difference in all indicators between the bilateral surgeries. In the second eye surgery, patients in the 1-week interval group experienced more severe pain, less cooperation, longer estimated operation duration, and a greater MCP1 than those in the 1-day interval group. CONCLUSION: Patients undergoing second eye ICL surgery had decreased nervousness, increased pain, decreased cooperation, and satisfaction, and increased MCP1 compared to the first eye surgery. It is recommended that an interval of about one week should be avoided between bilateral surgeries when developing a surgical schedule to improve patients' cooperation, satisfaction, and comfort.


Asunto(s)
Lentes Intraoculares , Miopía , Lentes Intraoculares Fáquicas , Humanos , Masculino , Femenino , Implantación de Lentes Intraoculares , Miopía/cirugía , Ojo , Dolor/cirugía
10.
Gut ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38599786

RESUMEN

OBJECTIVE: Probiotic Lactococcus lactis is known to confer health benefits to humans. Here, we aimed to investigate the role of L. lactis in colorectal cancer (CRC). DESIGN: L. lactis abundance was evaluated in patients with CRC (n=489) and healthy individuals (n=536). L. lactis was isolated from healthy human stools with verification by whole genome sequencing. The effect of L. lactis on CRC tumourigenesis was assessed in transgenic Apc Min/+ mice and carcinogen-induced CRC mice. Faecal microbiota was profiled by metagenomic sequencing. Candidate proteins were characterised by nano liquid chromatography-mass spectrometry. Biological function of L. lactis conditioned medium (HkyuLL 10-CM) and functional protein was studied in human CRC cells, patient-derived organoids and xenograft mice. RESULTS: Faecal L. lactis was depleted in patients with CRC. A new L. lactis strain was isolated from human stools and nomenclated as HkyuLL 10. HkyuLL 10 supplementation suppressed CRC tumourigenesis in Apc Min/+ mice, and this tumour-suppressing effect was confirmed in mice with carcinogen-induced CRC. Microbiota profiling revealed probiotic enrichment including Lactobacillus johnsonii in HkyuLL 10-treated mice. HkyuLL 10-CM significantly abrogated the growth of human CRC cells and patient-derived organoids. Such protective effect was attributed to HkyuLL 10-secreted proteins, and we identified that α-mannosidase was the functional protein. The antitumourigenic effect of α-mannosidase was demonstrated in human CRC cells and organoids, and its supplementation significantly reduced tumour growth in xenograft mice. CONCLUSION: HkyuLL 10 suppresses CRC tumourigenesis in mice through restoring gut microbiota and secreting functional protein α-mannosidase. HkyuLL 10 administration may serve as a prophylactic measure against CRC.

12.
Theriogenology ; 221: 9-17, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38521007

RESUMEN

Semen cryopreservation represents a promising technology utilized for preserving high-quality chicken varieties in husbandry practices. However, the efficacy of this methodology is significantly impeded by the diminished quality of sperm. Metabolites, as the end products of metabolic reactions, serve as indicators of biological processes and offer insights into physiological conditions. In this study, we investigaged the sperm quality and alteration in metabolic profiles during the cryopreservation of Longyou Partridge Chicken semen. Following artificial semen collection, four groups of semen samples were established based on four points of the cryopreservation process (Ⅰ, fresh semen; Ⅱ, semen added extender and chilled at 4 °C for 30 min; Ⅲ, semen added cryoprotectants; Ⅳ, semen gradient freezed and stored in liquid nitrogen). Semen cryopreservation has a negative effect on the percentage of sperm in a straight-line trajectory (LIN), has no significant effect on total motile sperms (TM) or the proportion of sperm with typical morphology (NM). Metabolites were identified using LC-MS technique and analyses including Principal Component Analysis (PCA), Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA), Univariate statistical analysis, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database were employed to identify metabolites. A total of 2471 metabolites had been identified, with the majority of the list being made up of amino acids and their metabolites as well as benzene and substituted derivatives. Group II exhibits 882 metabolites with significantly elevated abundance relative to Group I, alongside 37 metabolites displaying decreased abundance. In Group III, 836 metabolites demonstrate notably augmented abundance compared to Group II, while 87 metabolites exhibit reduced abundance. Furthermore, Group IV showcases 513 metabolites with markedly heightened abundance in comparison to Group III, and 396 metabolites with decreased abundance. Specific metabolites such as 5-Hydroxylysine, Phosphocholine, and alpha-d-glucose-6-phosphate exhibited a progressive decline during the cryopreservation process, correlating with either dilution and chilling, cryoprotectant addition, or freezing. In conclusion, our investigation systematically examined the changes of seminal metabolome and sperm quality throughout the cryopreservation process of rooster semen.


Asunto(s)
Preservación de Semen , Semen , Masculino , Animales , Semen/fisiología , Pollos/fisiología , Motilidad Espermática , Preservación de Semen/veterinaria , Preservación de Semen/métodos , Criopreservación/veterinaria , Criopreservación/métodos , Espermatozoides/fisiología , Análisis de Semen/veterinaria , Crioprotectores/farmacología , Crioprotectores/metabolismo
13.
Eur J Med Res ; 29(1): 208, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38549160

RESUMEN

OBJECTIVE: Secondary hyperparathyroidism (SHPT) is a common complication of chronic kidney disease (CKD). Hungry bone syndrome (HBS) after parathyroidectomy (PTX) is a serious complication, which can lead to diarrhea, convulsion, arrhythmia and even death. This study was aimed to determine the risk factors for HBS after PTX in dialysis patients with SHPT and construct a nomogram prediction model to predict the incidence of postoperative complications. METHODS: Clinical data were collected from 80 maintenance hemodialysis (MHD) patients with SHPT who received total PTX in the Second Hospital of Jilin University from January 2018 to September 2021. In line with the inclusion and exclusion criteria, totally 75 patients were finally enrolled for analysis. Patients were divided into two groups for retrospective analysis according to the severity of postoperative HBS, including HBS group and non-HBS (N-HBS) group. Univariate and multivariate logistic regression analyses were conducted to determine the risk factors for postoperative HBS. Afterwards, the receiver operating characteristic (ROC) curves were plotted based on the statistical analysis results, aiming to compare the prediction effects of different predicting factors. Finally, the nomogram was established to evaluate the occurrence probability of postoperative complications predicted by the risk factors. RESULTS: Among the 75 patients, 32 had HBS (HBS group), while 43 did not have HBS (N-HBS group). Univariate analysis results indicated that, the preoperative intact parathyroid hormone (iPTH) and serum alkaline phosphatase (ALP) levels in HBS group were significantly higher than those in N-HBS group, while preoperative hemoglobin and preoperative albumin (Alb) levels were significantly lower than those in N-HBS group. As discovered by multivariate logistic regression analysis, preoperative iPTH (OR = 1.111, P = 0.029) and ALP (OR = 1.010, P < 0.001) were the independent risk factors for postoperative HBS. ROC curve analysis suggested that the area under the curve (AUC) values of these two indicators were 0.873 and 0.926, respectively (P < 0.0001). Subsequently, the nomogram model for predicting HBS was constructed. The model verification results indicated that the predicted values were basically consistent with the measured values, with the C-index of 0.943 (95% CI 0.892-0.994). Besides, the calibration curve was consistent with the ideal curve, demonstrating the favorable accuracy and discrimination of the model. CONCLUSIONS: Preoperative iPTH and preoperative ALP are the risk factors for postoperative HBS, which can be used to guide the early clinical intervention.


Asunto(s)
Enfermedades Óseas Metabólicas , Hiperparatiroidismo Secundario , Hipocalcemia , Humanos , Paratiroidectomía/efectos adversos , Paratiroidectomía/métodos , Diálisis Renal/efectos adversos , Estudios Retrospectivos , Nomogramas , Hipocalcemia/epidemiología , Hipocalcemia/etiología , Hipocalcemia/cirugía , Hiperparatiroidismo Secundario/etiología , Hiperparatiroidismo Secundario/cirugía , Hormona Paratiroidea , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía
14.
Artículo en Inglés | MEDLINE | ID: mdl-38518126

RESUMEN

Objective: This study analyzes the relationship between ADHD, family relationships, lifestyle, and food intolerance. Methods: This study consisted of 240 children who received treatment at the researchers' hospital from January 2022 to November 2022. Out of these, 120 children belonged to the ADHD group, while the remaining 120 children were part of the healthy control group. The researchers compared these two groups of children on factors such as family relationships, lifestyle, and food intolerance. Results: The general data of the two groups were not statistically significant but comparable (P > .05); family relationships, lifestyle, and food intolerance all affected children with ADHD (P < .01). Conclusion: In the investigation of children with ADHD compared to healthy children, the influence of family relationships, lifestyle, and food intolerance can all cause ADHD.

15.
FEBS J ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38525648

RESUMEN

In recent years, a few asparaginyl endopeptidases (AEPs) from certain higher plants have been identified as efficient peptide ligases with wide applications in protein labeling and cyclic peptide synthesis. Recently, we developed a NanoLuc Binary Technology (NanoBiT)-based peptide ligase activity assay to identify more AEP-type peptide ligases. Herein, we screened 61 bamboo species from 16 genera using this assay and detected AEP-type peptide ligase activity in the crude extract of all tested bamboo leaves. From a popular bamboo species, Bambusa multiplex, we identified a full-length AEP-type peptide ligase candidate (BmAEP1) via transcriptomic sequencing. After its zymogen was overexpressed in Escherichia coli and self-activated in vitro, BmAEP1 displayed high peptide ligase activity, but with considerable hydrolytic activity. After site-directed mutagenesis of its ligase activity determinants, the mutant zymogen of [G238V]BmAEP1 was normally overexpressed in E. coli, but failed to activate itself. To resolve this problem, we developed a novel protease-assisted activation approach in which trypsin was used to cleave the mutant zymogen and was then conveniently removed via ion-exchange chromatography. After the noncovalently bound cap domain was dissociated from the catalytic core domain under acidic conditions, the recombinant [G238V]BmAEP1 displayed high peptide ligase activity with much lower hydrolytic activity and could efficiently catalyze inter-molecular protein ligation and intramolecular peptide cyclization. Thus, the engineered bamboo-derived peptide ligase represents a novel tool for protein labeling and cyclic peptide synthesis.

16.
Biochem Biophys Res Commun ; 706: 149766, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38484568

RESUMEN

Secretory myeloid-derived growth factor (MYDGF) exerts beneficial effects on organ repair, probably via a plasma membrane receptor; however, the identity of the expected receptor has remained elusive. In a recent study, MYDGF was reported as an agonist of the sphingosine-1-phosphate receptor 2 (S1PR2), an A-class G protein-coupled receptor that mediates the functions of the signaling lipid, sphingosine-1-phosphate (S1P). In the present study, we conducted living cell-based functional assays to test whether S1PR2 is a receptor for MYDGF. In the NanoLuc Binary Technology (NanoBiT)-based ß-arrestin recruitment assay and the cAMP-response element (CRE)-controlled NanoLuc reporter assay, S1P could efficiently activate human S1PR2 overexpressed in human embryonic kidney (HEK) 293T cells; however, recombinant human MYDGF, overexpressed either from Escherichia coli or HEK293 cells, had no detectable effect. Thus, the results demonstrated that human MYDGF is not a ligand of human S1PR2. Considering the high conservation of MYDGF and S1PR2 in evolution, MYDGF is also probably not a ligand of S1PR2 in other vertebrates.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos , Receptores de Lisoesfingolípidos , Esfingosina/análogos & derivados , Animales , Humanos , Receptores de Esfingosina-1-Fosfato , Receptores de Lisoesfingolípidos/genética , Receptores de Lisoesfingolípidos/metabolismo , Ligandos , Células HEK293 , Lisofosfolípidos/farmacología
17.
Sci Total Environ ; 925: 171775, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38499095

RESUMEN

Aerosol and cloud acidity are essential to human health, ecosystem health and productivity, as well as climate effects. The main chemical composition of cloud water greatly varies in different regions, resulting in substantial differences in the pH of cloud water. However, the influences of the anthropogenic emissions of acidic gases and substances, alkaline dust components, and dicarboxylic acids (diacids) on the ground concerning the acidity of cloud water in the free troposphere of the Guanzhong Plain, China, remain clear. In this study, cloud water and PM2.5 samples were simultaneously collected in the troposphere (Mt. Hua, 2060 m a.s.l). The results indicated that the cloud water was alkaline (pH = 7.6) and PM2.5 was acidic (pH = 3.2). These results showed the neutral property of clouds collected in the heavily polluted Guanzhong Plain, although most previous studies always considered acidity as a marker of pollution. The sulfate (SO42-), nitrate (NO3-), and ammonium (NH4+) (SNA) of particulate matter and cloud water in the same period were compared. SO42- was dominant in particulate matters (accounting for 63.4 % of the total SNA) but substantially decreased in cloud water (only 30.1 % of the total SNA), whereas NO3- and NH4+ increased from 28.5 % and 8.2 % to 39.8 % and 30.2 %, respectively. This could be attributed to the complex formation mechanism and sources of SO42- and NO3- in the cloud. The results of ion balance indicated that a significant deficit of inorganic anion equivalents was observed in the cloud water samples. The high concentration of diacids in the cloud phase (1237.4 µg L-1) may facilitate the formation of salt complexes with NH4+, thus influencing the acidity of the cloud water. The pH of cloud water has increased in recent decades due to the sustained reduction of sulfur dioxide, which may also affect the acidity of future precipitation.

18.
Chem Biol Interact ; 394: 110969, 2024 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-38522565

RESUMEN

It is well-established that the reduced Memory B cells (MBCs) play an important role in the pathogenesis of ulcerative colitis (UC), rendering them a potential therapeutic target for UC intervention. Astragalus polysaccharide (APS), a primary active constituent derived from the classic traditional Chinese medicine Astragalus membranaceus (AM), has been used for centuries in the treatment of UC in both human and animal subjects due to its renowned immunomodulatory properties. However, it is unknown whether APS can regulate MBCs to alleviate experimental colitis. In the present investigation, the murine colitis was successfully induced using dextran sulphate sodium (DSS) and subsequently treated with APS for a duration of 7 days. APS exhibited significant efficacy in reducing the disease activity index (DAI), colonic weight index, the index of colonic weight/colonic length. Furthermore, APS mitigated colonic pathological injuries, restored the colonic length, elevated the immunoglobulin A (IgA), transforming growth factor-ß1 (TGF-ß1) and interleukin (IL)-10 levels, while concurrently suppressing IgG, IgM, IL-6, tumor necrosis factor alpha (TNF-α) levels. Crucially, the quantities of MBCs, IgA+MBCs and forkhead box P3 (Foxp3+) MBCs were notably increased along with a concurrent decrease in IgG1+MBCs, IG2a+MBCs, IgG2b+MBCs after APS administration in colitis mice. Additionally, the Mitotracker red expressions of MBCs and their subgroups demonstrated a significantly up-regulation. Meanwhile, the transcriptomics analysis identified mitochondrial metabolism as the predominant and pivotal mechanism underlying APS-mediated mitigation of DSS-induced colitis. Key differentially expressed genes, including B-cell linker (BLNK), aldehyde dehydrogenase 1A1 (ALDH1A1), B-cell lymphoma 6 (BCL-6), B-lymphocyte-induced maturation protein 1 (Blimp-1), paired box gene 5 (PAX5), purinergic 2 × 7 receptor (P2X7R), B Cell activation factor (BAFF), B Cell activation factor receptor (BAFFR), CD40, nuclear factor kappa-B (NF-κB), IL-6 and so on were implicated in this process. These mRNA expressions were validated through quantitative polymerase chain reaction (qPCR) and immunohistochemistry. These findings revealed that APS effectively restored MBCs and their balance to ameliorate DSS-induced colitis, which was potentially realized via promoting mitochondrial metabolism to maintain MBCs activation.

20.
Adv Mater ; : e2312237, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38363019

RESUMEN

Inverted inorganic perovskite solar cells (PSCs) is potential as the top cells in tandem configurations, owing to the ideal bandgap, good thermal and light stability of inorganic perovskites. However, challenges such as mismatch of energy levels between charge transport layer and perovskite, significant non-radiative recombination caused by surface defects, and poor water stability have led to the urgent need for further improvement in the performance of inverted inorganic PSCs. Herein, the fabrication of efficient and stable CsPbI3-x Brx PSCs through surface treatment of (3-mercaptopropyl) trimethoxysilane (MPTS), is reported. The silane groups in MPTS can in situ crosslink in the presence of moisture to build a 3-dimensional (3D) network by Si-O-Si bonds, which forms a hydrophobic layer on perovskite surface to inhibit water invasion. Additionally, -SH can strongly interact with the undercoordinated Pb2+ at the perovskite surface, effectively minimizing interfacial charge recombination. Consequently, the efficiency of the inverted inorganic PSCs improves dramatically from 19.0% to 21.0% under 100 mW cm-2 illumination with MPTS treatment. Remarkably, perovskite films with crosslinked MPTS exhibit superior stability when soaking in water. The optimized PSC maintains 91% of its initial efficiency after aging 1000 h in ambient atmosphere, and 86% in 800 h of operational stability testing.

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