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1.
Materials (Basel) ; 17(7)2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38612109

RESUMEN

Numerous sources have already demonstrated that varying annealing rates can result in distinct toughness and brittleness in glass. To determine the underlying mechanisms driving this phenomenon, molecular dynamic (MD) simulations were employed to investigate the microstructure of aluminosilicate glasses under different cooling rates, and then uniaxial stretching was performed on them under controlled conditions. Results indicated that compared with short-range structure, cooling rate has a greater influence on the medium-range structure in glass, and it remarkably affects the volume of voids. Both factors play a crucial role in determining the brittleness of the glass. The former adjusts network connectivity to influence force transmission by manipulating the levels of bridging oxygen (BO) and non-bridging oxygen (NBO), and the latter accomplishes the objective of influencing brittleness by modifying the environmental conditions that affect the changes in BO and NBO content. The variation in the void environment results in differences in the strategies of the changes in BO and NBO content during glass stress. These findings stem from the excellent response of BO and NBO to the characteristic points of stress-strain curves during stretching. This paper holds importance in understanding the reasons behind the effect of cooling rates on glass brittleness and in enhancing our understanding of the ductile/brittle transition (DTB) in glass.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38685575

RESUMEN

Rumen fungi play an essential role in the breakdown of dietary fibrous components, facilitating the provision of nutrients and energy to the host animals. This study investigated the fermentation characteristics and effects on rumen microbiota of yak rumen anaerobic fungus Orpinomyces sp. YF3 in goat rumen fluid, both with and without fungal flora, utilizing anaerobic fermentation bottles. Crushed and air-dried wheat straw served as the fermentation substrate, and cycloheximide was used to eradicate microorganisms from the rumen fluid of dairy goats. The experiment compromised four treatment groups (2×2 factorial design): control (C); yak fungus group (CF, Orpinomyces sp. YF3); goat fungi eliminated group (CA, antibiotic: 0.25 mg/mL cycloheximide); goat fungi eliminated+yak fungus group (CAF). Each treatment had six replicates. Fermentation characteristics and microbial composition of the fermentation media were analyzed using one-way analysis of variance and high-throughput sequencing technology. The findings revealed that in the Orpinomyces sp. YF3 addition group (CF and CAF groups), there were significant increases in ammonia nitrogen concentration by 70%, total volatile fatty acids (VFA) by 53%, as well as acetate, isobutyrate, and valerate concentrations, and the ratio of acetate to propionate (p < 0.05), while the propionate proportion declined by 13%, alongside a reduction of butyrate concentration (p < 0.05). Similarly, in the CF and CAF groups, there were a notable increase in the relative abundance of Bacteroidota, Synergistota, Desulfobacterota, Actinobacteria, and Fusobacteriota, alongside a decrease in the relative abundance of Fibrobacterota and Proteobacteria (p < 0.05). Bacteria exhibiting increased relative abundance were positively correlated with the activity of carboxymethyl cellulase and avicelase, total VFA concentration, and acetate proportion, while showing a negatively correlation with propionate proportion. In conclusion, supplementing rumen fermentation media with yak rumen anaerobic fungus Orpinomyces sp. YF3 led to an increase in bacteria associated with fibre degradation and acetic acid production, a decrease in propionate-producing bacteria, enhanced the activity of plant cell wall degrading enzymes, and promoted cellulose degradation, ultimately elevating total VAF concentration and acetate proportion. This presents a novel approach to enhance roughage utilization in ruminants.

3.
Langmuir ; 40(17): 9265-9279, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38636094

RESUMEN

Heterogeneous catalytic systems with water as the solvent often have the disadvantage of cross-contamination, while concerns about the purification and workup of the aqueous phase after reactions are rare in the lab or industry. In this context, designing and developing the functional selective solid adsorbent and revealing the adsorption mechanism can provide a new strategy and guidelines for constructing supported heterogeneous catalysts to address these issues. Herein, we report the stable composite adsorbent (Fe/ATP@PPy: magnetic Fe3O4/attapulgite with the polypyrrole shell) that features an integrated multifunctional surface, which can effectively tune the selective adsorption processes for Cu2+, Co2+, and Ni2+ ions and nitrobenzene via the cooperative chemisorption/physisorption in an aqueous system. The adsorption experiments showed that Fe/ATP@PPy displayed significantly higher adsorption selectivity for Ni2+ than Cu2+ and Co2+ ions, especially which exhibited an approximate 100.00% removal for both Ni2+ ions and nitrobenzene in the mixture system with a low concentration. Furthermore, combined tracking adsorption of Ni2+ ions and X-ray photoelectron spectroscopy characterization confirmed that the effective adsorption occurs via ion transfer coordination; the pathway was further validated at the molecular level through theoretical modeling. In addition, the selective adsorption mechanism was proposed based on the adsorption experiment, characterization, and the corresponding density functional theory calculation.

4.
Metabolites ; 14(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38535310

RESUMEN

To investigate the difference between rumen-protected niacin (RPN) and rumen-protected nicotinamide (RPM) in the transcriptome of genes relating to the lipid metabolism of the liver of periparturient dairy cows, 10 healthy Chinese Holstein cows were randomly divided into two groups and fed diets supplemented with 18.4 g/d RPN or 18.7 g/d RPM, respectively. The experiment lasted from 14 days before to 21 days after parturition. Liver biopsies were taken 21 days postpartum for transcriptomic sequencing. In addition, human LO2 cells were cultured in a medium containing 1.6 mmol/L of non-esterified fatty acids and 1 mmol/L niacin (NA) or 2 mmol/L nicotinamide (NAM) to verify the expression of the 10 genes selected from the transcriptomic analysis of the liver biopsies. The expression of a total of 9837 genes was detected in the liver biopsies, among which 1210 differentially expressed genes (DEGs) were identified, with 579 upregulated and 631 downregulated genes. These DEGs were associated mainly with lipid metabolism, oxidative stress, and some inflammatory pathways. Gene ontology (GO) enrichment analysis showed that 355 DEGs were enriched in 38 GO terms. The differences in the expression of these DEGs between RPN and RPM were predominantly related to the processes of steroid catabolism, steroid hydroxylase, monooxygenase activity, oxidoreductase activity, hemoglobin binding, and ferric iron binding, which are involved mainly in lipid anabolism and redox processes. The expressions of FADS2, SLC27A6, ARHGAP24, and THRSP in LO2 cells were significantly higher (p < 0.05) while the expressions of BCO2, MARS1, GARS1, S100A12, AGMO, and OSBPL11 were significantly lower (p < 0.05) on the NA treatment compared to the NAM treatment, indicating that NA played a role in liver metabolism by directly regulating fatty acid anabolism and transport, inflammatory factor expression, and oxidative stress; and NAM functioned more as a precursor of nicotinamide adenine dinucleotide (NAD, coenzyme I) and nicotinamide adenine dinucleotide phosphate (NADP, coenzyme II) to participate indirectly in biological processes such as ether lipid metabolism, cholesterol metabolism, energy metabolism, and other processes.

5.
Chem Commun (Camb) ; 60(31): 4121-4139, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38533605

RESUMEN

The development of efficient hydrogen release and storage processes to provide environmentally friendly hydrogen solutions for mobile energy storage systems (MESS) stands as one of the most challenging tasks in addressing the energy crisis and environmental degradation. The catalytic dehydrogenative coupling of methanol and amines (DCMA) and its reverse are featured by high capacity for hydrogen release and storage, enhanced capability to purify the produced hydrogen, avoidance of carbon emissions and singular product composition, offering the environmentally and operationally benign strategy of overcoming the challenges associated with MESS. Particularly, the cycle between these two processes within the same catalytic system eliminates the need for collecting and transporting spent fuel back to a central facility, significantly facilitating easy recharging. Despite the promising attributes of the above strategy for environmentally friendly hydrogen solutions, challenges persist, primarily due to the high thermodynamic barriers encountered in methanol dehydrogenation and amide hydrogenation. By systematically summarizing various reaction mechanisms and pathways involving Ru-, Mn-, Fe-, and Mo-based catalytic systems in the development of catalytic DCMA and its reverse and the cycling between the two, this review highlights the current research landscape, identifies gaps, and suggests directions for future investigations to overcome these challenges. Additionally, the critical importance of developing efficient catalytic systems that operate under milder conditions, thereby facilitating the practical application of DCMA in MESS, is also underscored.

6.
Sci Rep ; 14(1): 3723, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355890

RESUMEN

Trichostrongylus colubriformis is a parasitic helminth that primarily infects small ruminants, causing substantial economic losses in the livestock industry. Exploring the microbiome of this helminth might provide insights into the potential influence of its microbial community on the parasite's survival. We characterised the intestinal microbiome of T. colubriformis that had been collected from the duodenum of sheep, and compared the helminth microbiome with the duodenal microbiome of its host, aiming to identify contributions from the helminth's environment. At the same time, we explored the isolation of fastidious organisms from the harvested helminth. Primary alpha and beta diversity analyses of bacterial species revealed statistically significant differences between the parasite and the host, in terms of species richness and ecological composition. 16S rRNA differential abundance analysis showed that Mycoplasmoides and Stenotrophomonas were significantly present in T. colubriformis but not in the duodenal microbiome of the sheep. Furthermore, two bacteria, Aeromonas caviae and Aeromonas hydrophila, were isolated from T. colubriformis. Examinations of the genome highlight differences in genome size and profiles of antimicrobial resistance genes. Our results suggest that T. colubriformis carries a specific bacterial community that could be supporting the helminth's long-term survival in the host's digestive system.


Asunto(s)
Parásitos , Enfermedades de las Ovejas , Tricostrongiliasis , Ovinos/genética , Animales , Trichostrongylus , Tricostrongiliasis/veterinaria , Tricostrongiliasis/genética , Tricostrongiliasis/parasitología , Parásitos/genética , ARN Ribosómico 16S/genética , Enfermedades de las Ovejas/genética , Recuento de Huevos de Parásitos/veterinaria
7.
Sci Total Environ ; 913: 169750, 2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38163596

RESUMEN

Shale gas, with its abundance and lower carbon footprint compared to other fossil fuels, is an important bridge fuel in the ongoing energy transition. However, a notable concern in shale gas exploration is fugitive methane emissions during the extraction, development, and transport of natural gas. While most existing works evaluate methane emissions released by well fracking, completion and operation, the greenhouse footprint of unproductive shale gas wells (often abandoned or orphaned) has received little scrutiny. A large fraction of these emissions from abandoned shale gas wells are due to the diffusive transport of methane trapped in nanoporous shale matrix, which is poorly understood. Here, we develop a theoretical kinetic approach to predict methane diffusive flux from heterogeneous shale matrix. Our theoretical model is based on a layer sequence formulation and accurately considers multiple flow mechanisms, including viscous flow, gas slippage, and Knudsen diffusion and their mutual interactions. The model is validated against the observed methane diffusion data obtained from high-pressure and high-temperature experimental measurements on Marcellus shale. We find that methane diffusive flux increases as reservoir pressure decreases. We estimate methane emission due to diffusive transport up to 20 × 103 m3 per well per day, which is comparable to emissions from flowback fluid. For the first time, unrecovered natural gas in the shale matrix is demonstrated to be the main source of methane emissions from abandoned shale gas wells. Given the long-lasting nature of diffusive transport to shale gas seepage, it is suggested that regulatory requirements should be implemented to provide long-term monitoring of methane emissions from abandoned shale gas wells.

8.
ACS Omega ; 9(3): 3885-3893, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38284039

RESUMEN

N2-hydraulic compound fracturing (NHCF) is an innovative technology aimed at addressing coalbed methane development challenges in low-permeability, low-pressure coal reservoirs in China. However, limited research has been focused on the evolution of damage zones, pore pressure fields, and fluid pressure characteristics in this context. In this paper, we establish a finite element seepage equation based on the volumetric opening model and construct a finite element model for horizontal well stage fracturing. We used the physical and mechanical parameters specific to coal reservoirs in the Xinjing coal mine. Subsequently, we conducted numerical simulations of N2 fracturing (NF), hydraulic fracturing (HF), and NHCF using ANSYS. The results indicate that the initiation-fracturing pressure of NHCF is lower than that of HF but higher than NF, but the steady-fracturing pressure is higher than HF and NF. Moreover, numerical simulation shows that under the same water injection volume, the total volumetric opening formed by NHCF is about 2 times that of HF, NF is the smallest, and the damage zone and pore pressure field caused by NHCF are the largest. Finally, when comparing the casing pressure curve of NHCF by field test with the fluid pressure curve of wellbore obtained from numerical simulation, we observe a strong correlation; the steady fracturing pressure of NF is about 13 MPa, which is basically consistent with the numerical simulation, and the steady- fracturing pressure of HF after NF is about 27 MPa, which is slightly lower than the 30 MPa in numerical simulation. This is because in the numerical simulation, the reservoir parameters after NF can be inherited to the subsequent HF, which cannot be done in the field test. This study presents a novel method for numerical fluid fracturing simulation, offering a fresh perspective on the subject.

9.
Appl Environ Microbiol ; 90(1): e0154823, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38112425

RESUMEN

In bacteria, the second messenger cyclic di-GMP (c-di-GMP) is synthesized and degraded by multiple diguanylate cyclases (DGCs) and phosphodiesterases. A high level of c-di-GMP induces biofilm formation and represses motility. WspR, a hybrid response regulator DGC, produces c-di-GMP when it is phosphorylated. FlhF, a signal recognition particle-type GTPase, is initially localized to the cell poles and is indispensable for polar flagellar localization in Pseudomonas aeruginosa. In this study, we report that deletion of flhF affected biofilm formation and the c-di-GMP level in P. aeruginosa. Phenotypic analysis of a flhF knockout mutant revealed increased biofilm formation, wrinkled colonies on Congo red agar, and an elevated c-di-GMP level compared to the wild-type strain, PAO1. Yeast and bacterial two-hybrid systems showed that FlhF binds to the response regulator HsbR, and HsbR binds to WspR. Deletion of hsbR or wspR in the ΔflhF background abolished the phenotype of ΔflhF. In addition, confocal microscopy demonstrated that WspR-GFP was distributed throughout the cytoplasm and formed a visible cluster at one cell pole in PAO1 and ΔhsbR, but it was mainly distributed as visible clusters at the lateral side of the periplasm and with visible clusters at both cell poles in ΔflhF. These findings suggest that FlhF influences the subcellular cluster and localization of WspR and negatively modulates WspR DGC activity in a manner dependent on HsbR. Together, our findings demonstrate a novel mechanism for FlhF modulating the lifestyle transition between motility and biofilm via HsbR to regulate the DGC activity of WspR.IMPORTANCECyclic di-GMP (c-di-GMP) is a second messenger that controls flagellum biosynthesis, adhesion, virulence, motility, exopolysaccharide production, and biofilm formation in bacteria. Recent research has shown that distinct diguanylate cyclases (DGCs) or phosphodiesterases (PDEs) produce highly specific outputs. Some DGCs and PDEs contribute to the total global c-di-GMP concentration, but others only affect local c-di-GMP in a microenvironment. However, the underlying mechanisms are unclear. Here, we report that FlhF affects the localization and DGC activity of WspR via HsbR and is implicated in local c-di-GMP signaling in Pseudomonas aeruginosa. This study establishes the link between the c-di-GMP signaling system and the flagellar localization and provides insight for understanding the complex regulatory network of c-di-GMP signaling.


Asunto(s)
Dietilestilbestrol/análogos & derivados , Proteínas de Escherichia coli , Pseudomonas aeruginosa , Pseudomonas aeruginosa/genética , Proteínas de Escherichia coli/genética , GMP Cíclico/metabolismo , Biopelículas , Liasas de Fósforo-Oxígeno/genética , Hidrolasas Diéster Fosfóricas/metabolismo , Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica
10.
Small ; : e2308002, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38084459

RESUMEN

In order to reveal the dynamic response characteristic of thin film thermocouples (TFTCs), the nichrome/nisil (NiCr/NiSi) TFTCs are prepared onto the glass substrate. With short pulse infrared laser system, NiCr/NiSi TFTCs are dynamically calibrated. The thermoelectric electromotive force (TEF) curves of NiCr/NiSi TFTCs are recorded by the memory hicorder system, which could reflect TEF signals with resolution ratio in nanosecond and microvolt, simultaneously. With increasing laser energy from 15.49 to 29.59 mJ, TEF curves display more and more violent oscillation, even negative value. The results show that the bounce of thermal energy happens between two interfaces of TFTCs because the thermal conductivity of glass and air is significantly lower than that of NiSi/NiCr TFTCs. The bounce of thermal energy results in the obvious decrease of nNiCr and nNiSi , as well as oscillation of TEF. For laser energy in 29.59 mJ, the bounce of thermal energy in NiCr film could result in nNiCr < nNiSi . Then, TEF value appears abnormal negative value. Based on the results, the complex thermal energy transport process in TFTCs dynamic calibration is revealed, which results in the oscillation of thermal energy and TEF signal.

11.
Sci Prog ; 106(4): 368504231216832, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38105488

RESUMEN

Adverse pressure gradients can cause severe flow separation within typical S-shaped inlets. This results in a total pressure distortion at the aerodynamic interface plane (AIP). The expansive bending pipe, where flow separation also occurs due to the adverse pressure gradient, is the basis for investigations into S-shaped inlets. In this study, surface dielectric barrier discharge (SDBD) plasma actuators are used to moderate the total pressure distortion in the AIP of an expansive bending pipe under a 10 m/s incoming flow. Also, the influences of actuation voltage amplitude and pulsed frequency on the total pressure distortion of the AIP are investigated under two plasma actuation modes, nanosecond pulsed SDBD and alternating current (AC) SDBD. Under optimal actuation parameters, the nanosecond pulsed SDBD and the AC-SDBD can reduce the distortion index by 14.93% and 32.22%, respectively. The results demonstrate the effectiveness of SDBD plasma actuators in suppressing flow separation within expansive bending pipes.

12.
Front Neurol ; 14: 1237661, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38125833

RESUMEN

Background: To assess the clinical and safety outcomes of endovascular treatment (EVT) administered more than 24 h after the onset of symptoms in patients with acute ischemic stroke resulting from anterior circulation large-vessel occlusion or stenosis (AIS-ACLVO/S). Methods: We enrolled consecutive AIS-ACLVO/S patients who received EVT in our hospital between January 2019 and February 2022 and divided them into two groups based on the time from AIS onset to EVT: EVT < 24 h group and EVT >24 h group. The successful reperfusion (modified thrombolysis in cerebral infarction, [mTICI] ≥2b), 90-day modified Rankin Scale score (mRS), intracranial hemorrhage (ICH), and symptomatic ICH (sICH), as well as mortality, were analyzed in the two groups of patients. Results: A total of 239 patients were included in the study, with 214 patients in the EVT < 24 h group (67.8 ± 0.8 years, 126 males) and 25 patients in the EVT > 24 h group (62.80 ± 2.0 years, 22 males). Both groups were similar in terms of hypertension, diabetes history, responsible vessels, and Alberta stroke program early computed tomography scores (p > 0.05). However, the EVT < 24 h group had significantly higher age, history of atrial fibrillation, proportion of patients receiving intravenous thrombolysis, and NIHSS scores before EVT than the EVT > 24 h group. AIS etiology differed between the groups, with more cases of large artery atherosclerosis in the EVT > 24-h group and more cases of cardioembolism in the EVT < 24-h group. Successful reperfusion (mTICI ≥2b), ICH, and sICH were similar between the groups. The 90-day functional independence rate (mRS ≤ 2) was significantly higher in the EVT > 24-h than in the EVT < 24-h group (80% vs. 39.7%, p < 0.001), while the 90-day mortality rate was lower in the EVT > 24-h group (0% vs. 24.8%, p < 0.001). Conclusion: In our study, we found that EVT beyond 24 h of symptom onset in patients selected with multimodal MR screening, was associated with high functional independence rates and low mortality. Larger or randomized studies are needed to confirm these findings.

13.
Front Immunol ; 14: 1223675, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37822937

RESUMEN

Objective: The utility of metagenomic next-generation sequencing (mNGS) in the diagnosis of tuberculous meningitis (TBM) remains uncertain. We performed a meta-analysis to comprehensively evaluate its diagnostic accuracy for the early diagnosis of TBM. Methods: English (PubMed, Medline, Web of Science, Cochrane Library, and Embase) and Chinese (CNKI, Wanfang, and CBM) databases were searched for relevant studies assessing the diagnostic accuracy of mNGS for TBM. Review Manager was used to evaluate the quality of the included studies, and Stata was used to perform the statistical analysis. Results: Of 495 relevant articles retrieved, eight studies involving 693 participants (348 with and 345 without TBM) met the inclusion criteria and were included in the meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the summary receiver-operating characteristic curve of mNGS for diagnosing TBM were 62% (95% confidence interval [CI]: 0.46-0.76), 99% (95% CI: 0.94-1.00), 139.08 (95% CI: 8.54-2266), 0.38 (95% CI: 0.25-0.58), 364.89 (95% CI: 18.39-7239), and 0.97 (95% CI: 0.95-0.98), respectively. Conclusions: mNGS showed good specificity but moderate sensitivity; therefore, a more sensitive test should be developed to assist in the diagnosis of TBM.


Asunto(s)
Tuberculosis Meníngea , Humanos , Tuberculosis Meníngea/diagnóstico , Sensibilidad y Especificidad , Curva ROC , Secuenciación de Nucleótidos de Alto Rendimiento , Bases de Datos Factuales
14.
Medicine (Baltimore) ; 102(36): e34922, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37682135

RESUMEN

OBJECTIVE: To compare the effect of laparoscopic surgery and open surgery on the quality of life of patients with colorectal cancer (CRC) in the growth period after the operation, and to provide a reference for surgical treatment decisions of patients with CRC. METHODS: PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane databases were searched through May 7, 2022 for clinical studies comparing the postoperative quality of life in CRC patients who underwent laparoscopic surgery with those who underwent open surgery. Data were extracted from eligible studies following rigorous quality review. All studies included patient numbers, surgery type, follow-up length, and quality of life scores. RESULTS: A total of 6 studies were included, resulting in significantly better physical functioning scores with laparoscopic versus open surgery. (Standardized mean difference = 0.45; 95% CI (0.15, 0.75), P = .003). However, in general health, social functioning, bodily pain, vitality, quality of life index, Global Quality Scale, physical component summary and mental component summary, there was no telling difference between the 2 surgical therapies. CONCLUSION: Compared with open surgery, laparoscopic surgery has weak advantages. There was no noteworthy difference in the long-term quality of life between the 2 surgical treatments for CRC patients. Whether laparoscopic surgery can bring more improvement to the quality of life of patients with CRC needs more high-quality clinical randomized studies to verify.


Asunto(s)
Neoplasias Colorrectales , Laparoscopía , Humanos , Calidad de Vida , Bases de Datos Factuales , MEDLINE , Neoplasias Colorrectales/cirugía
15.
Front Microbiol ; 14: 1202752, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37700862

RESUMEN

Tuberculous meningitis (TBM) is the most common type of central nervous system tuberculosis (TB) and has the highest mortality and disability rate. Early diagnosis is key to improving the prognosis and survival rate of patients. However, laboratory diagnosis of TBM is often difficult due to its paucibacillary nature and sub optimal sensitivity of conventional microbiology and molecular tools which often fails to detect the pathogen. The gold standard for TBM diagnosis is the presence of MTB in the CSF. The recognised methods for the identification of MTB are acid-fast bacilli (AFB) detected under CSF smear microscopy, MTB cultured in CSF, and MTB detected by polymerase chain reaction (PCR). Currently, many studies consider that all diagnostic techniques for TBM are not perfect, and no single technique is considered simple, fast, cheap, and efficient. A definite diagnosis of TBM is still difficult in current clinical practice. In this review, we summarise the current state of microbiological and molecular biological diagnostics for TBM, the latest advances in research, and discuss the advantages of these techniques, as well as the issues and challenges faced in terms of diagnostic effectiveness, laboratory infrastructure, testing costs, and clinical expertise, for clinicians to select appropriate testing methods.

16.
Biochem Biophys Res Commun ; 676: 149-157, 2023 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-37517217

RESUMEN

Glioblastoma (GBM) has a high degree of invasiveness, which is largely attributed to the invalidation of current therapy and the unclear tumor growth mechanism. Ras related GTP binding B (RRAGB) is a family member of the Ras-homologous GTPases. The effect of RRAGB on tumor growth has been recognized, but its influences on GBM progression are ill-defined. Here, in our research, a significantly decreased expression of RRAGB in GBM tissues by using TCGA databases and glioma samples is observed. According to Kaplan-Meier (KM) analysis, RRAGB low expression leads to a significant decrease of overall survival rate of patients, and is associated with the classification of WHO grade, histological type and age increase. Functional enrichment analysis reveals that the pathway of enrichment includes cell cycle arrest, extracellular matrix (ECM) processes and PI3K/AKT signal. Thereafter, our cell experiments confirm an obvious decrease of RRAGB in several GBM cell lines. It should be noted that RRAGB promotion strongly reduces the proliferation, migration and invasion of GBM cells and induces cell cycle arrest in G0/G1 phase. RRAGB up-regulation significantly decreases the expression of PI3K, phosphorylated AKT, mTOR and S6K in GBM cell lines. Surprisingly, we further find that RRAGB-restrained proliferative, migratory and invasive properties of GBM cells are markedly offset after promoting AKT activation, accompanied with restored phosphorylation of mTOR and S6K, elucidating that AKT signaling blockage is partially indispensable for RRAGB to play its anti-cancer role in GBM. Animal studies confirmed that RRAGB over-expression obviously inhibits the tumor growth both in the xenograft and orthotopic mouse glioma models, along with improved overall survival rates. In short, we provide evidence that RRAGB is a potential therapeutic target and prognostic marker for GBM treatment.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glioma , Proteínas de Unión al GTP Monoméricas , Ratones , Animales , Humanos , Glioblastoma/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias Encefálicas/patología , Proliferación Celular , Línea Celular Tumoral , Apoptosis , Serina-Treonina Quinasas TOR/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas de Unión al GTP Monoméricas/metabolismo
17.
Genomics ; 115(5): 110667, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37315873

RESUMEN

Scavenger receptor class A, member 5 (SCARA5) has been identified a novel tumor suppressor in several cancers. However, the functional and underlying mechanism of SCARA5 in bladder cancer (BC) need investigation. Here, we found SCARA5 expression was downregulated in both BC tissues and cell lines. Low SCARA5 in BC tissues was associated with a shorter overall survival. Moreover, SCARA5 overexpression reduced BC cell viability, colony formation, invasion, and migration. Further investigation demonstrated that the expression of SCARA5 was negatively regulated by miR-141. Furthermore, the long non-coding RNA prostate cancer associated transcript 29 (PCAT29) inhibited the proliferation, invasion, and migration of BC cells by sponging miR-141. Luciferase activity assays revealed that PCAT29 targeted miR-141 and miR-141 targeted SCARA5. In conclusion, SCARA5, as a downstream factor of the PCAT29/miR-141 axis, inhibited the proliferation, migration, and invasion of BC cells. These findings provide novel insights into the detailed molecular mechanisms of BC development.


Asunto(s)
MicroARNs , ARN Largo no Codificante , Neoplasias de la Vejiga Urinaria , Masculino , Humanos , Línea Celular Tumoral , Proliferación Celular/genética , Genes Supresores de Tumor , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología , MicroARNs/genética , Movimiento Celular/genética , ARN Largo no Codificante/genética , Regulación Neoplásica de la Expresión Génica , Receptores Depuradores de Clase A/genética , Receptores Depuradores de Clase A/metabolismo
18.
Metabolites ; 13(5)2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37233635

RESUMEN

To investigate the effects of rumen-protected choline (RPC) and rumen-protected nicotinamide (RPM) on liver metabolic function based on transcriptome in periparturient dairy cows, 10 healthy Holstein dairy cows with similar parity were allocated to RPC and RPM groups (n = 5). The cows were fed experimental diets between 14 days before and 21 days after parturition. The RPC diet contained 60 g RPC per day, and the RPM diet contained 18.7 g RPM per day. Liver biopsies were taken 21 days after calving for the transcriptome analysis. A model of fat deposition hepatocytes was constructed using the LO2 cell line with the addition of NEFA (1.6 mmol/L), and the expression level of genes closely related to liver metabolism was validated and divided into a CHO group (75 µmol/L) and a NAM group (2 mmol/L). The results showed that the expression of a total of 11,023 genes was detected and clustered obviously between the RPC and RPM groups. These genes were assigned to 852 Gene Ontology terms, the majority of which were associated with biological process and molecular function. A total of 1123 differentially expressed genes (DEGs), 640 up-regulated and 483 down-regulated, were identified between the RPC and RPM groups. These DEGs were mainly correlated with fat metabolism, oxidative stress and some inflammatory pathways. In addition, compared with the NAM group, the gene expression level of FGF21, CYP26A1, SLC13A5, SLCO1B3, FBP2, MARS1 and CDH11 in the CHO group increased significantly (p < 0.05). We proposed that that RPC could play a prominent role in the liver metabolism of periparturient dairy cows by regulating metabolic processes such as fatty acid synthesis and metabolism and glucose metabolism; yet, RPM was more involved in biological processes such as the TCA cycle, ATP generation and inflammatory signaling.

19.
Sci Total Environ ; 889: 164095, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37207766

RESUMEN

One major cyclical environmental parameter within the underground mine space is the fluctuation of relative humidity, which varies daily and seasonally. Therefore, moisture and dust particle interactions are inevitable and indirectly control dust transport and fate. After being released into the environment, the coal dust particles stay there for a long period depending upon several parameters such as particle size, specific gravity, ventilation etc. Due to their smaller size, nano-sized coal dust particles could remain in the mine environment indefinitely while interacting with it. Correspondingly the primary characteristic of nano-sized coal dust particles could get modified. The nano-sized coal dust samples were prepared in the lab and characterized using different techniques. The prepared samples were allowed to interact with moisture using the dynamic vapor sorption technique. It was found that the lignite coal dust particles could adsorb up to 10 times more water vapor than the bituminous coal dusts. Oxygen content is one of the primary factors in deciding the total effective moisture adsorption in the nano-sized coal dust, with moisture adsorption proportional to the oxygen content of the coal. This means that lignite coal dust is more hygroscopic when compared to bituminous coal dust. GAB and Freundlich's models perform well for water uptake modeling. Because of interaction with atmospheric moisture, particularly swelling, adsorption, moisture retention, and particle size changes, such interactions will significantly change the physical characteristics of nano-sized coal dust. This will affect the transport and deposition behavior of coal dust in the mine atmosphere.


Asunto(s)
Minas de Carbón , Vapor , Carbón Mineral , Polvo/análisis , Minerales , Oxígeno
20.
Sci Total Environ ; 878: 163163, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37003338

RESUMEN

Coal dust is the major hazardous pollutant in the coal mining environment. Recently environmentally persistent free radicals (EPFRs) were identified as one of the key characteristics which could impart toxicity to the particulates released into the environment. The present study used Electron Paramagnetic Resonance (EPR) spectroscopy to analyze the characteristics of EPFRs present in different types of nano-size coal dust. Further, it analyzed the stability of the free radicals in the respirable nano-size coal dust and compared their characteristics in terms of EPR parameters (spin counts and g-values). It was found that free radicals in coal are remarkably stable (can remain intact for several months). Also, Most of the EPFRs in the coal dust particles are either oxygenated carbon centered or a mixture of carbon and oxygen-centered free radicals. EPFRs concentration in the coal dust was found to be proportional to the carbon content of coal. The characteristic g-values were found to be inversely related to the carbon content of coal dust. The spin concentrations in the lignite coal dust were between 3.819 and 7.089 µmol/g, whereas the g-values ranged from 2.00352 to 2.00363. The spin concentrations in the bituminous coal dust were between 11.614 and 25.562 µmol/g, whereas the g-values ranged from 2.00295 to 2.00319. The characteristics of EPFRs present in coal dust identified by this study are similar to the EPFRs, which were found in other environmental pollutants such as combustion-generated particulates, PM2.5, indoor dust, wildfires, biochar, haze etc., in some of the previous studies. Considering the toxicity analysis of environmental particulates containing EPFRs similar to those identified in the present study, it can be confidently hypothesized that the EPFRs in the coal dust might play a major role in modulating the coal dust toxicity. Hence, it is recommended that future studies should analyze the role of EPFR-loaded coal dust in mediating the inhalation toxicity of coal dust.

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