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1.
Plant J ; 2024 Oct 04.
Article in English | MEDLINE | ID: mdl-39364769

ABSTRACT

Plant trichomes are an excellent model for studying cell differentiation and development, providing crucial defenses against biotic and abiotic stresses. There is a well-established inverse relationship between trichome density and aphid prevalence, indicating that higher trichome density leads to reduced aphid infestations. Here we present the cloning and characterization of a dominant quantitative trait locus, HIC (hirsute cotton), which significantly enhances cotton trichome density. This enhancement leads to markedly improved resistance against cotton aphids. The HIC encodes an HD-ZIP IV transcriptional activator, crucial for trichome initiation. Overexpression of HIC leads to a substantial increase in trichome density, while knockdown of HIC results in a marked decrease in density, confirming its role in trichome regulation. We identified a variant in the HIC promoter (-810 bp A to C) that increases transcription of HIC and trichome density in hirsute cotton compared with Gossypium hirsutum cultivars with fewer or no trichomes. Interestingly, although the -810 variant in the HIC promoter is the same in G. barbadense and hirsute cotton, the presence of a copia-like retrotransposon insertion in the coding region of HIC in G. barbadense causes premature transcription termination. Further analysis revealed that HIC positively regulates trichome density by directly targeting the EXPANSIN A2 gene, which is involved in cell wall development. Taken together, our results underscore the pivotal function of HIC as a primary regulator during the initial phases of trichome formation, and its prospective utility in enhancing aphid resistance in superior cotton cultivars via selective breeding.

2.
Cancer Lett ; 605: 217284, 2024 Oct 02.
Article in English | MEDLINE | ID: mdl-39366545

ABSTRACT

Chemoresistance remains a formidable challenge in pancreatic ductal adenocarcinoma (PDAC) treatment, necessitating a comprehensive exploration of underlying molecular mechanisms. This work aims to investigate the dynamic epigenetic landscape during the development of gemcitabine resistance in PDAC, with a specific focus on super-enhancers and their regulatory effects. We employed well-established gemcitabine-resistant (Gem-R) PDAC cell lines to perform high-throughput analyses of the epigenome, enhancer connectome, and transcriptome. Our findings revealed notable alterations in the epigenetic landscape and genome architecture during the transition from gemcitabine-sensitive to -resistant PDAC cells. Remarkably, we observed substantial plasticity in the activation status of super-enhancers, with a considerable proportion of these cis-elements becoming deactivated in chemo-resistant cells. Furthermore, we pinpointed the NDRG1 super-enhancer (NDRG1-SE) as a crucial regulator in gemcitabine resistance among the loss-of-function super-enhancers. NDRG1-SE deactivation induced activation of WNT/ß-catenin signaling, thereby conferring gemcitabine resistance. This work underscores a NDRG1 super-enhancer deactivation-driven ß-catenin pathway activation as a crucial regulator in the acquisition of gemcitabine-resistance. These findings advance our understanding of PDAC biology and provide valuable insights for the development of effective therapeutic approaches against chemoresistance in this malignant disease.

3.
Clin Genitourin Cancer ; : 102192, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39261258

ABSTRACT

OBJECTIVE: To provide a comprehensive understanding of the clinical features of patients with synchronous and metachronous upper tract urothelial carcinoma (UTUC) and bladder urothelial carcinoma (BUC) and inform surgical and postoperative adjuvant treatment planning. PATIENTS AND METHOD: A total of 292 consecutive patients with synchronous and metachronous UTUC-BUC were retrospectively enrolled and were categorized into three groups: (1) UTUC metachronous BUC (N = 185, UTUC-mBUC), (2) BUC-metachronous UTUC (N = 43, BUC-mUTUC), (3) synchronous UTUC-BUC (N = 64, sUTUC-BUC). We compared pathological characteristics and survival data among groups with Wilcoxon's rank sum tests, Pearson's chi-squared, and the Kaplan-Meier method. RESULTS: In the sUTUC-BUC group, a higher proportion of patients exhibited UTUC tumors with grade G3 (56%, P = .001) and stage T4 (6%, P < .001) than group UTUC-mBUC (G3 = 16%, T4 = 0%). The proportion of patients with variant histology subtype in group sUTUC-BUC was higher than that of metachronous UTUC-BUC, involving squamous (P = .003), adenoid (P = .012), and sarcomatoid (P < .001) differentiation. It was also observed that the maximum diameter of the UTUC tumor of group sUTUC-BUC (median = 3.5) was significantly larger than group UTUC-mBUC (median = 2.5, P = .002) and group BUC-mUTUC (median = 2.2, P < .001). Notably, sUTUC-BUC has an increased risk of cancer-specific death compared with UTUC-mBUC (P < .001) and BUC-mUTUC (P < .001). On multivariable Cox regression, synchronous UTUC-BUC was an independent predictor of both RFS (P < .001; vs. UTUC-mBUC: HR 0.555, P = .004; vs. BUC-mUTUC: HR 0.279, P < .001) and CSS (P < .001, HR 29.737). Moreover, sUTUC-BUC showed a better response to intravesical therapy and chemotherapy with higher cancer-specific survival (P < .001) and recurrence-free survival (P = .034). CONCLUSIONS: The prognosis and pathological characteristics among different metachronous and synchronous UTUC and BUC were diverse. The synchronous UTUC-BUC group showed variant histology subtype, high-grade tumors, advanced tumors, multifocal UTUC, worse cancer-specific survival, but better response to intravesical therapy and chemotherapy.

4.
Sci Rep ; 14(1): 17828, 2024 08 01.
Article in English | MEDLINE | ID: mdl-39090210

ABSTRACT

The liver plays a vital role in lipid synthesis and metabolism in poultry. To study the functional genes more effectively, it is essential to screen of reliable reference genes in the chicken liver, including females, males, embryos, as well as the Leghorn Male Hepatoma (LMH) cell line. Traditional reference gene screening involves selecting commonly used housekeeping genes (HKGs) for RT-qPCR experiments and using different algorithms to identify the most stable ones. However, this approach is limited in selecting the best reference gene from a small pool of HKGs. High-throughput sequencing technology may offer a solution to this limitation. This study aimed to identify the most consistently expressed genes by utilizing multiple published RNA-seq data of chicken liver and LMH cells. Subsequently, the stability of the newly identified reference genes was assessed in comparison to previously validated stable poultry liver expressed reference genes and the commonly employed HKGs using RT-qPCR. The findings indicated that there is a higher degree of similarity in stable expression genes between female and male liver (such as LSM14A and CDC40). In embryonic liver, the optimal new reference genes were SUDS3, TRIM33, and ERAL1. For LMH cells, the optimal new reference genes were ALDH9A1, UGGT1, and C21H1orf174. However, it is noteworthy that most HKGs did not exhibit stable expression across multiple samples, indicating potential instability under diverse conditions. Furthermore, RT-qPCR experiments proved that the stable expression genes identified from RNA-seq data outperformed commonly used HKGs and certain validated reference genes specific to poultry liver. Over all, this study successfully identified new stable reference genes in chicken liver and LMH cells using RNA-seq data, offering researchers a wider range of reference gene options for RT-qPCR in diverse situations.


Subject(s)
Chickens , Genes, Essential , Liver , Real-Time Polymerase Chain Reaction , Reference Standards , Animals , Chickens/genetics , Liver/metabolism , Male , Female , Real-Time Polymerase Chain Reaction/standards , Real-Time Polymerase Chain Reaction/methods , Gene Expression Profiling/standards , Gene Expression Profiling/methods , Cell Line, Tumor , Chick Embryo
5.
Int J Biol Macromol ; 276(Pt 1): 134156, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39098458

ABSTRACT

Magnetic biochar (MBC) was obtained from pepper straw by impregnation-microwave pyrolysis method. The pyrolysis temperature and FeCl3 impregnation concentration were investigated on the structural properties of MBC and the adsorption of methyl orange (MO) in water. Characterization results showed that pyrolysis temperature and iron species significantly increased the specific surface area of MBC, which could reach the maximum of 2038.61 m2/g, and also provided more active adsorption sites by promoting the generation of graphitized structures and surface polar functional groups. MBC0.2-900 was selected as the adsorbent for MO with the maximum adsorption capacity reached 437.18 mg·g-1, 3.4 times higher than the virgin biochar. The adsorption process was dominated by chemisorption as well as spontaneous and exothermic. The adsorption mechanisms included pore-filling interaction, π-π EDA interaction, electrostatic interaction, hydrogen bonding, and Lewis acid-base electron interaction. In addition, MBC also exhibited excellent separability and reusability as a low-cost adsorbent. This study provided some theoretical foundation and technological support for producing high-performance biochar and developing pollutant removal technology in wastewater.


Subject(s)
Azo Compounds , Charcoal , Water Pollutants, Chemical , Water Purification , Charcoal/chemistry , Adsorption , Azo Compounds/chemistry , Azo Compounds/isolation & purification , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Kinetics
6.
Animals (Basel) ; 14(15)2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39123699

ABSTRACT

Research on hepatic steatosis in animal husbandry has been a prominent area of study. Developing an appropriate in vitro cellular steatosis model is crucial for comprehensively investigating the mechanisms involved in liver lipid deposition in poultry and for identifying potential interventions to address abnormalities in lipid metabolism. The research on the methods of in vitro liver steatosis in chickens, particularly the effects of different fat mixtures, is still lacking. In this study, LMH cells were utilized to investigate the effects of OA, SO, PA, SP, and their pairwise combinations on steatosis development, with the aim of identifying the optimal conditions for inducing steatosis. Analysis of triglyceride (TG) content in LMH cells revealed that OA and SP had limited efficacy in increasing TG content, while a combination of SO and PA in a 1:2 ratio exhibited the highest TG content. Moreover, Oil Red O staining results in LMH cells demonstrated that the combination treatment had a more pronounced induction effect compared to 0.375 mM SO. Additionally, RNA-seq analysis showed that 0.375 mM SO significantly influenced the expression of genes associated with fatty acid metabolism compared to the control group, whereas the combination of SO and PA led to an enrichment of key GO terms associated with programmed cell death. These findings suggest that varying conditions of cellular steatosis could lead to distinct disruptions in gene expression. The optimal conditions for inducing steatosis in LMH cells were also tested on chicken embryonic liver cells and embryos. TG detection and Oil Red O staining assays showed that the combination of SO and PA successfully induced steatosis. However, the gene expression pattern differed from that of LMH cells. This study lays the foundations for further investigations into avian hepatic steatosis.

7.
Poult Sci ; 103(9): 103980, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38959666

ABSTRACT

Utilizing publicly available RNA-seq data to screen for ideal reference genes is more efficient and accurate than traditional methods. Previous studies have identified optimal reference genes in various chicken tissues, but none have specifically focused on the oviduct (including the infundibulum, magnum, isthmus, uterus, and vagina), which is crucial for egg production. Identifying stable reference genes in the oviduct is essential for improving research on gene expression levels. This study investigated genes with consistent expression patterns in the chicken oviduct, encompassing both individual oviduct tract tissues and the entire oviduct, by utilizing multiple RNA-seq datasets. The screening results revealed the discovery of 100 novel reference genes in each segment of oviduct tissues, primarily associated with cell cycle regulation and RNA binding. Moreover, the majority of housekeeping genes (HKGs) showed inconsistent expression levels across distinct samples, suggesting their lack of stability under varying conditions. The stability of the newly identified reference genes was assessed in comparison to previously validated stable reference genes in chicken oviduct and commonly utilized HKGs, employing traditional reference gene screening methods. HERPUD2, CSDE1, VPS35, PBRM1, LSM14A, and YWHAB were identified to be suitable novel reference gene for different parts of the oviduct. HERPUD2 and YWHAB were reliable for gene expression normalization throughout the oviduct tract. Furthermore, overexpression and interference assays in DF1 cells showed LSM14A and YWHAB play a crucial role in cell proliferation, highlighting the importance of these newly reference genes for further research. Overall, this study has expanded the options for reference genes in RT-qPCR experiments in different segments of the chicken oviduct and the entire oviduct.


Subject(s)
Chickens , Oviducts , Real-Time Polymerase Chain Reaction , Animals , Chickens/genetics , Female , Oviducts/metabolism , Real-Time Polymerase Chain Reaction/veterinary , Real-Time Polymerase Chain Reaction/methods , Real-Time Polymerase Chain Reaction/standards , Genes, Essential , Avian Proteins/genetics , Avian Proteins/metabolism , Reference Standards , Gene Expression Profiling/veterinary , Gene Expression Profiling/standards
8.
Front Plant Sci ; 15: 1381071, 2024.
Article in English | MEDLINE | ID: mdl-38699538

ABSTRACT

Introduction: The biosynthesis of secondary metabolites like anthocyanins is often governed by metabolic gene clusters (MGCs) in the plant ancestral genome. However, the existence of gene clusters specifically regulating anthocyanin accumulation in certain organs is not well understood. Methods and results: In this study, we identify MGCs linked to the coloration of cotton reproductive organs, such as petals, spots, and fibers. Through genetic analysis and map-based cloning, we pinpointed key genes on chromosome A07, such as PCC/GhTT19, which is involved in anthocyanin transport, and GbBM and GhTT2-3A, which are associated with the regulation of anthocyanin and proanthocyanidin biosynthesis. Our results demonstrate the coordinated control of anthocyanin and proanthocyanidin pathways, highlighting the evolutionary significance of MGCs in plant adaptation. The conservation of these clusters in cotton chromosome A07 across species underscores their importance in reproductive development and color variation. Our study sheds light on the complex biosynthesis and transport mechanisms for plant pigments, emphasizing the role of transcription factors and transport proteins in pigment accumulation. Discussion: This research offers insights into the genetic basis of color variation in cotton reproductive organs and the potential of MGCs to enhance our comprehension of plant secondary metabolism.

9.
Gene ; 918: 148479, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-38636815

ABSTRACT

The GHRL, LEAP2, and GHSR system have recently been identified as important regulators of feed intake in mammals and chickens. However, the complete cloning of the quail GHRL (qGHRL) and quail LEAP2 (qLEAP2) genes, as well as their association with feed intake, remains unclear. This study cloned the entire qGHRL and qLEAP2 cDNA sequence in Chinese yellow quail (Coturnix japonica), including the 5' and 3' untranslated regions. Sanger sequencing analysis revealed no missense mutations in the coding region of qGHRL and qLEAP2. Subsequently, phylogenetic analysis and protein homology alignment were conducted on the qGHRL and qLEAP2 in major poultry species. The findings of this research indicated that the qGHRL and qLEAP2 sequences exhibit a high degree of similarity with those of chicken and turkey. Specifically, the N-terminal 6 amino acids of GHRL mature peptides and all the mature peptide sequence of LEAP2 exhibited consistent patterns across all species examined. The analysis of tissue gene expression profiles indicated that qGHRL was primarily expressed in the proventriculus and brain tissue, whereas qLEAP2 exhibited higher expression levels in the intestinal tissue, kidney, and liver tissue, differing slightly from previous studies conducted on chicken. It is necessary to investigate the significance of elevated expression of qGHRL in brain and qLEAP2 in kidney in the future. Further research has shown that the expression of qLEAP2 can quickly respond to changes in different energy states, whereas qGHRL does not exhibit the same capability. Overall, this study successfully cloned the complete cDNA sequences of qGHRL and qLEAP2, and conducted a comprehensive examination of their tissue expression profiles and gene expression levels in the main expressing organs across different energy states. Our current findings suggested that qLEAP2 is highly expressed in the liver, intestine, and kidney, and its expression level is regulated by feed intake.


Subject(s)
Cloning, Molecular , Phylogeny , Animals , Ghrelin/genetics , Ghrelin/metabolism , Avian Proteins/genetics , Avian Proteins/metabolism , Eating/genetics , Amino Acid Sequence , Gene Expression Profiling/methods , Coturnix/genetics , Coturnix/metabolism , Chickens/genetics , Chickens/metabolism , Quail/genetics , Polymorphism, Genetic
10.
J Mol Graph Model ; 130: 108778, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38652998

ABSTRACT

SIRT6 is of interest for its promising effect in the treatment of aging-related diseases. Studies have shown quercetin (QUE) and its derivatives have varying degrees of effect on the catalytic effect of SIRT6. In the research, the effect of QUE on the protein-substrate interaction in the SIRT6-mediated mono-ADP ribosylation system was investigated by conventional molecular dynamics (MD) simulations combined with MM/PBSA binding free energy calculations. The results show that QUE can bind stably to SIRT6 with the binding energy of -22.8 kcal/mol and further affect the atomic interaction between SIRT6 and NAD+ (or H3K9), resulting in an increased affinity between SIRT6-NAD+ and decreased SIRT6-H3K9 binding capacity. At the same time, the binding of QUE can also alter some structural characteristics of the protein, with large shifts occurring in the residue regions involving the N-terminal (residues 1-27), Rossmann fold regions (residues 55-92), and ZBD (residues 164-179). Thus, QUE shows great potential as a scaffold for the design of novel potent SIRT6 modulators.


Subject(s)
Molecular Dynamics Simulation , Protein Binding , Quercetin , Sirtuins , Quercetin/chemistry , Quercetin/pharmacology , Sirtuins/chemistry , Sirtuins/metabolism , Humans , Binding Sites , NAD/chemistry , NAD/metabolism , Thermodynamics , Molecular Docking Simulation , Substrate Specificity , Hydrogen Bonding , Protein Conformation
11.
J Biomol Struct Dyn ; : 1-10, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38533567

ABSTRACT

The unmarked potential drug molecule azamulin has been found to be a specific inhibitor of CYP3A4 and CYP3A5 in recent years, but this molecule also shows different binding ability and affinity to the two CYP3A isoforms. In order to explore the microscopic mechanism, conventional molecular dynamics (MD) simulation methods were performed to study the dynamic interactions between two isoforms and azamulin. The simulation results show that the binding of the ligand leads to different structural properties of two CYP3A proteins. First of all, compared with apo-CYP3A4, the binding of the ligand azamulin can lead to changes in the structural flexibility of CYP3A4, i.e., holo-CYP3A4 is more flexible than apo-CYP3A4. The structural changes of CYP3A5 are just the opposite. The ligand binding increases the rigidity of CYP3A5. Furthermore, the representative structures of the production phase in the MD simulation were in details analyzed to obtain the microscopic interactions between the ligand azamulin and two CYP3A isoforms at the atomic level. It is speculated that the difference of composition and interaction of the active sites is the fundamental cause of the change of structural properties of the two proteins.Communicated by Ramaswamy H. Sarma.

12.
Aging (Albany NY) ; 16(5): 4503-4517, 2024 02 26.
Article in English | MEDLINE | ID: mdl-38412322

ABSTRACT

BACKGROUND: Clinical studies have confirmed that Qingfei Dayuan (QFDY) granules are effective in the treatment of influenza and upper respiratory tract infections (URTIs) caused by pulmonary heat-toxin syndrome (PHTS). Granules of Chinese medicine formulations have become a widely used dosage form in clinical practice. With the continuous optimization of extraction technology, the advantages of Chinese medicine granules have been gradually demonstrated, but the price of Chinese medicine granules is generally higher than that of traditional dosage forms of Chinese medicine, and we support the rational use of the appropriate dosage of QFDY for patients with these conditions. Therefore, we set up half of the conventional dose as the low dose group, and designed the three-arm study to rigorously compare the efficacy difference of low-dose QFDY, QFDY and the placebo group, with the expectation of providing scientific support for the rational selection of the dose and the safe and effective use of the medicine in clinical practice. METHODS: We recruited 108 patients with clinical diagnoses of influenza and URTIs caused by PHTS to receive treatment at six hospitals in Hubei, China. Using a centralized randomization system, patients were randomly assigned at a 1:1:1 ratio to the QFDY, low-dose QFDY, or placebo control groups to receive the corresponding drug, and the study physicians, subjects, outcome assessors, and statisticians were unaware of group assignments. The primary outcome was the time to complete fever relief. Secondary outcomes included the efficacy of Chinese medicine in alleviating signs and symptoms and the disappearance rate of individual symptoms. Adverse events were monitored throughout the trial. RESULTS: A total of 108 patients were recruited. A total of 106 patients were included in the full analysis set (FAS). In the FAS analysis, there was no statistically significant difference in baseline of the three groups before treatment (P > 0.05). 1. Regarding the median time to complete fever relief, the QFDY, low-dose QFDY and placebo groups had median times of 26 h, 40 h and 48 h, respectively. The QFDY group had a shorter time to complete fever relief than the placebo group, and the difference was statistically significant (P < 0.05), while the low-dose QFDY group had a shorter time than the placebo group, but the difference was not statistically significant (P > 0.05). 2. In terms of the total efficacy of Chinese medicine in alleviating symptoms at the end of three full days of treatment, as well as the cure rate of red and sore throat, stuffy and runny nose, and sneezing, QFDY and low-dose QFDY were superior to the placebo, and the differences were statistically significant (P < 0.01). There was no statistical significance in the comparison between the QFDY group and the low-dose QFDY group (P > 0.05). 3. In terms of the headache cure rate after three full days of treatment, QFDY was superior to the placebo, with a statistically significant difference (P < 0.05), and there was no significant efficacy of low-dose QFDY. 4. Safety comparisons showed no serious adverse events and 30 minor adverse events, which were not clinically considered to be related to the drug and were not statistically significant. CONCLUSIONS: In the treatment of patients with influenza and URTIs caused by PHTS, which are mainly characterized by clinical symptoms such as red and sore throat, stuffy and runny nose, and sneezing, when fever is not obvious or low-grade fever is present, the use of low-dose QFDY to simply alleviate the clinical symptoms is recommended and preferred. Moreover, with its good safety profile, QFDY can be used in the treatment of patients with influenza and URTIs caused by PHTS, which can effectively shorten the duration of fever, significantly increase the total efficacy of Chinese medicine in alleviating symptoms after 3 days of treatment, and accelerate the recovery of symptoms such as red and sore throat, stuffy and runny nose, sneezing, and headache, etc. Clinical Trial Registration: http://www.chictr.org.cn. TRIAL NUMBER: ChiCTR2100043449. Registered on 18 February 2021.


Subject(s)
Drugs, Chinese Herbal , Influenza, Human , Pharyngitis , Respiratory Tract Infections , Humans , Influenza, Human/drug therapy , Sneezing , Fever/drug therapy , Headache , Rhinorrhea , Treatment Outcome
13.
Talanta ; 272: 125802, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38368834

ABSTRACT

A growing evidence showed that the terrestrial ecosystem was a greater sink for microplastics (MPs) compared with ocean. Owing to the limitation of pretreatment methods, there are few reports on the identification of small-sized MPs(<60 µm) in soil currently, which may led to an underestimation of the environmental risk of MPs in soil system. In this study, we established an efficient pretreatment method for MPs in soils by developing a novel device, Plastic Flotation and Separator system (PFSS). The device integrated the suspension, digestion and filtration procedures into one system, reducing the losses of pretreatment process. It was shown that the recovery of MPs with size of 45 µm was 90%, significantly surpassing that of the traditional pretreatment methods in this particle size range. Combined with the SEM-Raman technique, MPs with small size were accurately determined. This work provides an effective method for the extraction and determination of MPs in soils and is of significance for the risk assessment of MPs in soil system.

14.
Opt Express ; 32(3): 2959-2971, 2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38297531

ABSTRACT

The diffuse attenuation coefficient (Kd) is known to be closely related to the light transmittance of sea ice, which plays a critical role in the energy balance and biological processes of the upper ocean. However, the commercial instruments cannot easily measure Kd in sea ice because sea ice is a solid. The authors of this study are developing an instrument with a high spectral solution to measure the irradiance profile of sea ice and the irradiance in the atmosphere. Three Kd experiments were carried out, including two in-situ experiments in the Liaodong Bay and one in the laboratory. The results showed that the Kd of the sea ice varied with depth, and the values in adjacent sea ice layers differed by up to 2 times. In addition, due to changes in the climate environment, the Kd of sea ice showed temporal variations. For example, there was a 1.38-fold difference in the Kd values of the surface layer of sea ice at different times in 2022. The values in different sea ice layers also showed different trends over time, and the coefficient of determination (R2) of Kd between adjacent layers over time was as low as 0.008. To explain the driving mechanism of spatio-temporal variability of Kd, an additional experiment focusing on the physical microstructure of sea ice was conducted in Liaodong Bay in 2022. The result shows that the change in air bubbles in the sea ice may be the main the reason for the change in Kd. For example, when the sea ice was exchanging brine and bubbles with the atmosphere above and the seawater below, the highly absorbent particles in it tend to remain in their original position. Considering that the total absorption coefficient changed slightly, the bubbles with the characteristic of intense scattering were found to be the main factor influencing the Kd changes. This conclusion is supported by the fact that the value of R2 between the bubbles and Kd was 0.52. If climatic changes have led to an increase in the volume of bubbles, the more bubbles will increase the scattering properties of sea ice and lead to an increase in Kd. Conversely, the reduced bubble volume would reduce the scattering properties of sea ice, which in turn would reduce Kd.

15.
J Chem Phys ; 160(6)2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38341789

ABSTRACT

The microscopic mechanism of the energy transfer in cyclotrimethylene trinitramine (RDX) is of particular importance for the study of the energy release process in high-energy materials. In this work, an effective vibrational Hamiltonian based on normal modes (NMs) has been introduced to study the energy transfer process of RDX. The results suggest that the energy redistribution in RDX can be characterized as an ultrafast process with a time scale of 25 fs, during which the energy can be rapidly localized to the -NNO2 twisting mode (vNNO2), the N-N stretching mode (vN-N), and the C-H stretching mode (vC-H). Here, the vNNO2 and vN-N modes are directly related to the cleavage and dissociation of the N-N bond in RDX and, therefore, can be referred to as "active modes." More importantly, we found that the energy can be rapidly transferred from the vC-H mode to the vNNO2 mode due to their strong coupling. From this perspective, the vC-H mode can be regarded as an "energy collector" that plays a pivotal role in supplying energy to the "active modes." In addition, the bond order analysis shows that the dissociation of the N-N bonds of RDX follows a combined twisting and stretching path along the N-N bond. This could be an illustration of the further exothermic decomposition triggered by the accumulation of vibrational energy. The present study reveals the microscopic mechanism for the vibrational energy redistribution process of RDX, which is important for further investigation of the energy transfer process in high-energy materials.

16.
Int Urol Nephrol ; 56(6): 1919-1926, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38200364

ABSTRACT

PURPOSE: To present our initial experience in the management of multiple ureteral polyps with robotic or laparoscopic ileal ureter replacement (IUR). METHODS: Eight consecutive patients diagnosed with multiple ureteral polyps underwent robotic or laparoscopic IUR between July 2019 and November 2022. Unilateral IUR was performed in 5 patients with polyps in the left (n = 3) or right (n = 2) side, and 3 patients with bilateral multiple polyps underwent bilateral IUR. Demographic characteristics, perioperative data and follow-up outcomes were prospectively collected. RESULTS: A cohort of 5 male and 3 female patients (11 ureters) with a mean age of 32.8 ± 11.3 years were included. Among these patients, 5 presented with recurrent flank pain, 1 had hematuria, and 2 were asymptomatic. Four patients experienced prior failed surgical interventions. The mean length of diseased ureter was 11.9 ± 4.7 cm, with more than 10 cm in eight sides. All procedures were performed successfully. The mean operation time was 319 ± 87.6 min with 3 patients who simultaneously underwent intraoperative ureteroscopy. The mean length of ileal graft was 23.8 ± 5.8 cm. During the mean follow-up of 20.4 ± 12.8 months, one major complication, specifically incision infection, and four minor complications, including urinary infection (n = 3) and metabolic acidosis (n = 1), were observed. All patients presented symptom-free, with improved/stabilized hydronephrosis and no signs of restenosis. CONCLUSION: Robotic or laparoscopic IUR is a feasible, safe, and effective surgical option for patients with long ureteral defects caused by multiple polyps.


Subject(s)
Ileum , Laparoscopy , Polyps , Ureter , Ureteral Diseases , Humans , Male , Female , Adult , Ileum/surgery , Ureter/surgery , Polyps/surgery , Ureteral Diseases/surgery , Laparoscopy/methods , Robotic Surgical Procedures , Young Adult , Middle Aged , Minimally Invasive Surgical Procedures/methods , Urologic Surgical Procedures/methods
17.
PLoS One ; 19(1): e0293731, 2024.
Article in English | MEDLINE | ID: mdl-38241420

ABSTRACT

Prevention of Clostridium difficile infection is challenging worldwide owing to its high morbidity and mortality rates. C. difficile is currently being classified as an urgent threat by the CDC. Devising a new therapeutic strategy become indispensable against C. difficile infection due to its high rates of reinfection and increasing antimicrobial resistance. The current study is based on core proteome data of C. difficile to identify promising vaccine and drug candidates. Immunoinformatics and vaccinomics approaches were employed to construct multi-epitope-based chimeric vaccine constructs from top-ranked T- and B-cell epitopes. The efficacy of the designed vaccine was assessed by immunological analysis, immune receptor binding potential and immune simulation analyses. Additionally, subtractive proteomics and druggability analyses prioritized several promising and alternative drug targets against C. difficile. These include FMN-dependent nitroreductase which was prioritized for pharmacophore-based virtual screening of druggable molecule databases to predict potent inhibitors. A MolPort-001-785-965 druggable molecule was found to exhibit significant binding affinity with the conserved residues of FMN-dependent nitroreductase. The experimental validation of the therapeutic targets prioritized in the current study may worthy to identify new strategies to combat the drug-resistant C. difficile infection.


Subject(s)
Clostridioides difficile , Clostridioides difficile/metabolism , Molecular Docking Simulation , Epitopes, B-Lymphocyte , Bacterial Vaccines , Nitroreductases/metabolism , Epitopes, T-Lymphocyte , Computational Biology , Vaccines, Subunit
18.
Poult Sci ; 102(12): 103169, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37918133

ABSTRACT

The application of reverse transcription quantitative real-time PCR technology for the production of gene tissue expression profiles is a widely employed approach in molecular biology research. It is imperative to ascertain internal reference genes that exhibit stable expression across diverse tissues to ensure the precision of tissue gene expression profiles. While there have been studies documenting the most suitable reference genes for various tissues in chickens, there is a dearth of research on the identification of reference genes in the gastrointestinal (GI) tract of chickens. This study utilized 4 different algorithms (Delta CT, BestKeeper, NormFinder, and Genorm) to assess the stability of 19 internal reference genes in various GI tract tissues, including individual GI tract tissues, the anterior and posterior GI tract, and the entire GI tissue. The RefFinder software was employed to comprehensively rank these genes. The research findings successfully identified the most appropriate internal reference genes for each type of GI tissue. Furthermore, TBP, DNAJC24, Polr2b, RPL13, andAp2m exhibited stable expression in the entire and posterior GI tract, whereas HMBS, TBP, Ap2m, GUSB, DNAJC24, and RPL13 demonstrated stable expression in the anterior GI tract. However, the internal reference genes commonly utilized, namely ß-Actin, 18s RNA, and ALB, exhibit poor stability and are not advised for future investigations concerning gene expression in the GI region. Consequently, MUC2 and CDX1, 2 genes that specifically express in the gut, were chosen for examination to ascertain the stability of the aforementioned internal reference genes in this particular study. In summary, this study presents a relatively stable set of internal reference genes that can be employed to enhance the precision of quantifying mRNA expression levels in functional genes within the chicken GI tract.


Subject(s)
Chickens , Gene Expression Profiling , Animals , Chickens/genetics , Gene Expression Profiling/veterinary , Transcriptome , Real-Time Polymerase Chain Reaction/veterinary , Gastrointestinal Tract
19.
Chem Sci ; 14(37): 10096-10102, 2023 Sep 27.
Article in English | MEDLINE | ID: mdl-37772120

ABSTRACT

Quantum mechanics/molecular mechanics (QM/MM) and molecular dynamics (MD) methods were applied to systematically investigate the temperature-dependent phosphorescence emission of dibenzo[b,d]thiophen-2-yl(4-chlorophenyl)methanone (ClBDBT) and its derivatives. The calculated temperature-dependent spectra on the lowest triplet state (T1) are in good agreement with the experimental observations, which means that the two-component white light emission should stem from the T1 state. The further MD simulations demonstrate the existence of two mesomerism structures at room temperature which can emit two lights simultaneously. The multi-component light emissions induced by mesomerism structures have advantages in balancing the distribution of excitons which could be beneficial to obtain pure white light along with stable Commission Internationale de l'Éclairage (CIE) coordinates. We hope this mesomerism concept can be further used to design new white light emitters based on room-temperature phosphorescence.

20.
Molecules ; 28(18)2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37764388

ABSTRACT

The concerted elimination reaction class of peroxyl-hydroperoxyl alkyl radicals (•OOQOOH) plays a crucial role in the low-temperature combustion of normal-alkyl cyclohexanes. The generation of the relatively unreactive HO2 radicals in this reaction is one of the factors leading to the negative temperature coefficient (NTC) behavior, which hinders the low-temperature oxidation of normal-alkyl cyclohexanes. In this study, 44 reactions are selected and divided into 4 different subclasses according to the nature of the carbon atom where the H atom is eliminated and the reaction center position. Utilizing the CBS-QB3 method, we compute the energy barriers for the concerted elimination reactions of peroxyl-hydroperoxyl alkyl radicals. Following this, we assess both the high-pressure limit and pressure-dependent rate constants for all reactions by applying TST and RRKM/ME theory. These calculations allow for the development of rate rules, which come to fruition through an averaging process involving the rate constants of representative reactions within each subclass. Our work provides accurate rate constants and rate rules for this reaction class, which can aid in constructing more accurate combustion mechanisms for normal-alkyl cyclohexanes.

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