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1.
World J Gastrointest Surg ; 16(7): 2270-2280, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39087098

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignant tumors, and early screening is crucial to improving the survival rate of patients. The combination of colonoscopy and immune fecal occult blood detection has garnered significant attention as a novel method for CRC screening. Colonoscopy and fecal occult blood tests, when combined, can improve screening accuracy and early detection rates, thereby facilitating early intervention and treatment. However, certain risks and costs accompany it, making the establishment of a risk classification model crucial for accurate classification and management of screened subjects. AIM: To evaluate the feasibility and effectiveness of colonoscopy, immune fecal occult blood test (FIT), and risk-graded screening strategies in CRC screening. METHODS: Based on the randomized controlled trial of CRC screening in the population conducted by our hospital May 2020 to May 2023, participants who met the requirements were randomly assigned to a colonoscopy group, an FIT group, or a graded screening group at a ratio of 1:2:2 (after risk assessment, the high-risk group received colonoscopy, the low-risk group received an FIT test, and the FIT-positive group received colonoscopy). The three groups received CRC screening with different protocols, among which the colonoscopy group only received baseline screening, and the FIT group and the graded screening group received annual follow-up screening based on baseline screening. The primary outcome was the detection rate of advanced tumors, including CRC and advanced adenoma. The population participation rate, advanced tumor detection rate, and colonoscopy load of the three screening programs were compared. RESULTS: A total of 19373 subjects who met the inclusion and exclusion criteria were enrolled, including 8082 males (41.7%) and 11291 females (58.3%). The mean age was 60.05 ± 6.5 years. Among them, 3883 patients were enrolled in the colonoscopy group, 7793 in the FIT group, and 7697 in the graded screening group. Two rounds of follow-up screening were completed in the FIT group and the graded screening group. The graded screening group (89.2%) and the colonoscopy group (42.3%) had the lowest overall screening participation rates, while the FIT group had the highest (99.3%). The results of the intentional analysis showed that the detection rate of advanced tumors in the colonoscopy group was greater than that of the FIT group [2.76% vs 2.17%, odds ratio (OR) = 1.30, 95% confidence interval (CI): 1.01-1.65, P = 0.037]. There was no significant difference in the detection rate of advanced tumors between the colonoscopy group and the graded screening group (2.76% vs 2.35%, OR = 1.9, 95%CI: 0.93-1.51, P = 0.156), as well as between the graded screening group and the FIT group (2.35% vs 2.17%, OR = 1.09%, 95%CI: 0.88-1.34, P = 0.440). The number of colonoscopy examinations required for each patient with advanced tumors was used as an index to evaluate the colonoscopy load during population screening. The graded screening group had the highest colonoscopy load (15.4 times), followed by the colonoscopy group (10.2 times), and the FIT group had the lowest (7.8 times). CONCLUSION: A hierarchical screening strategy based on CRC risk assessment is feasible for screening for CRC in the population. It can be used as an effective supplement to traditional colonoscopy and FIT screening programs.

2.
World J Diabetes ; 15(7): 1551-1561, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39099830

RESUMEN

BACKGROUND: The impact of type 1 diabetes (T1D) on inflammatory bowel disease (IBD) remains unclear. AIM: To analyze the causal relationship between T1D and IBD using Mendelian ran-domization (MR). METHODS: Single nucleotide polymorphisms were sourced from FinnGen for T1D, IBD, ulcerative colitis (UC) and Crohn's disease (CD). Inverse variance-weighted, MR-Egger, and weighted median tests were used to assess exposure-outcome causality. The MR-Egger intercept was used to assess horizontal pleiotropy. Co-chran's Q and leave-one-out method were used to analyze heterogeneity and sensitivity, respectively. RESULTS: Our MR analysis indicated that T1D was associated with a reduced risk of IBD [odds ratio (OR): 0.959; 95% confidence interval (CI): 0.938-0.980; P < 0.001] and UC (OR: 0.960; 95%CI: 0.929-0.992; P = 0.015), with no significant association observed in terms of CD risk (OR: 0.966; 95%CI: 0.913-1.022; P = 0.227). The MR-Egger intercept showed no horizontal pleiotropy (P > 0.05). Cochran's Q and leave-one-out sensitivity analyses showed that the results were not heterogeneous (P > 0.05) and were robust. CONCLUSION: This MR analysis suggests that T1D serves as a potential protective factor against IBD and UC but is independent of CD.

3.
Shanghai Kou Qiang Yi Xue ; 33(3): 269-272, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-39104342

RESUMEN

PURPOSE: To investigate the feasibility and effect of free latissimus dorsi myocutaneous flap in the reconstruction of giant head and neck defects. METHODS: Free latissimus dorsi myocutaneous flap on the cadaver was simulated dissected, and measured by Image-Pro Plus 6.0 to assess the feasibility of repairing giant head and neck defects. Between May 2011 and September 2022, seven patients with giant head and neck defects of different causes repaired with the latissimus dorsi myocutaneous flap were retrospectively analyzed. RESULTS: The diameter of the initiating thoracodorsal artery was (4.03±0.56) mm, and the mean lengths of the arteriolar and venous pedicles of the latissimus dorsi myocutaneous flaps obtained from human specimens were (85.5±10.5) mm and (104±4.2) mm, respectively. Among 7 patients, 5 cases had scalp defects, the remaining 2 cases had neck defects. There were no substantial postoperative problems in the donor site, and all seven latissimus dorsi myocutaneous flaps were successfully transplanted. CONCLUSIONS: For the treatment of considerable head and neck deformities, the latissimus dorsi myocutaneous flap is an optimal muscle flap due to its abundance of tissue, enough length of vascular pedicles, and sufficient venous drainage.


Asunto(s)
Colgajo Miocutáneo , Procedimientos de Cirugía Plástica , Músculos Superficiales de la Espalda , Humanos , Músculos Superficiales de la Espalda/trasplante , Colgajo Miocutáneo/trasplante , Procedimientos de Cirugía Plástica/métodos , Estudios Retrospectivos , Cuello/cirugía , Cuello/anatomía & histología , Cabeza/cirugía , Cabeza/anatomía & histología , Neoplasias de Cabeza y Cuello/cirugía , Cadáver , Cuero Cabelludo/cirugía , Masculino
4.
Int J Med Mushrooms ; 26(10): 41-54, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39171630

RESUMEN

The initiation and formation of the "pinhead" is the key node in growth process of Ophiocordyceps sinensis (Chinese Cordyceps). The research on the mechanism of changes in this growth stage is the basis for realizing the industrialization of its artificial cultivation. Clarifying the mechanisms of pinhead initiation is essential for its further application. Here, we performed a comprehensive transcriptome analysis of pinhead initiation process in O. sinensis. Comparative transcriptome analysis revealed remarkable variation in gene expression and enriched pathways at different pinhead initiation stages. Gene co-expression network analysis by WGCNA identified 4 modules highly relevant to different pinhead initiation stages, and 23 hub genes. The biological function analysis and hub gene annotation of these identified modules demonstrated that transmembrane transport and nucleotide excision repair were the topmost enriched in pre-pinhead initiation stage, carbohydrate metabolism and protein glycosylation were specially enriched in pinhead initiation stage, nucleotide binding and DNA metabolic process were over-represented after pinhead stage. These key regulators are mainly involved in carbohydrate metabolism, synthesis of proteins and nucleic acids. This work excavated the candidate pathways and hub genes related to the pinhead initiation stage, which will serve as a reference for realizing the industrialization of artificial cultivation in O. sinensis.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Redes Reguladoras de Genes , Regulación Fúngica de la Expresión Génica , Cordyceps/genética , Cordyceps/crecimiento & desarrollo , Cordyceps/metabolismo , Cuerpos Fructíferos de los Hongos/genética , Cuerpos Fructíferos de los Hongos/crecimiento & desarrollo , Cuerpos Fructíferos de los Hongos/metabolismo , Hypocreales/genética , Hypocreales/metabolismo , Hypocreales/crecimiento & desarrollo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Pueblos del Este de Asia
5.
World J Clin Cases ; 12(23): 5320-5328, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39156092

RESUMEN

BACKGROUND: Breast cancer ranks as one of the most prevalent malignant tumors among women, significantly endangering their health and lives. While radical surgery has been a pivotal method for halting disease progression, it alone is insufficient for enhancing the quality of life for patients. AIM: To investigate the correlation between ultrasound characteristic parameters of breast cancer lesions and clinical efficacy in patients undergoing neoadjuvant chemotherapy (NAC). METHODS: Employing a case-control study design, this research involved 178 breast cancer patients treated with NAC at our hospital from July 2019 to June 2022. According to the Miller-Payne grading system, the pathological response, i.e. efficacy, of the NAC in the initial breast lesion after NAC was evaluated. Of these, 59 patients achieved a pathological complete response (PCR), while 119 did not (non-PCR group). Ultrasound characteristics prior to NAC were compared between these groups, and the association of various factors with NAC efficacy was analyzed using univariate and multivariate approaches. RESULTS: In the PCR group, the incidence of posterior echo attenuation, lesion diameter ≥ 2.0 cm, and Alder blood flow grade ≥ II were significantly lower compared to the non-PCR group (P < 0.05). The area under the curve values for predicting NAC efficacy using posterior echo attenuation, lesion diameter, and Alder grade were 0.604, 0.603, and 0.583, respectively. Also, rates of pathological stage II, lymph node metastasis, vascular invasion, and positive Ki-67 expression were significantly lower in the PCR group (P < 0.05). Logistic regression analysis identified posterior echo attenuation, lesion diameter ≥ 2.0 cm, Alder blood flow grade ≥ II, pathological stage III, vascular invasion, and positive Ki-67 expression as independent predictors of poor response to NAC in breast cancer patients (P < 0.05). CONCLUSION: While ultrasound characteristics such as posterior echo attenuation, lesion diameter ≥ 2.0 cm, and Alder blood flow grade ≥ II exhibit limited predictive value for NAC efficacy, they are significantly associated with poor response to NAC in breast cancer patients.

6.
Front Mol Neurosci ; 17: 1423132, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39156127

RESUMEN

Intracerebral hemorrhage (ICH) is the second most common subtype of stroke, characterized by high mortality and a poor prognosis. Despite various treatment methods, there has been limited improvement in the prognosis of ICH over the past decades. Therefore, it is imperative to identify a feasible treatment strategy for ICH. Mitochondria are organelles present in most eukaryotic cells and serve as the primary sites for aerobic respiration and energy production. Under unfavorable cellular conditions, mitochondria can induce changes in permeability through the opening of the mitochondrial permeability transition pore (mPTP), ultimately leading to mitochondrial dysfunction and contributing to various diseases. Recent studies have demonstrated that mPTP plays a role in the pathological processes associated with several neurodegenerative diseases including Parkinson's disease, Alzheimer's disease, Huntington's disease, ischemic stroke and ischemia-reperfusion injury, among others. However, there is limited research on mPTP involvement specifically in ICH. Therefore, this study comprehensively examines the pathological processes associated with mPTP in terms of oxidative stress, apoptosis, necrosis, autophagy, ferroptosis, and other related mechanisms to elucidate the potential mechanism underlying mPTP involvement in ICH. This research aims to provide novel insights for the treatment of secondary injury after ICH.

7.
PLoS Negl Trop Dis ; 18(8): e0012428, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39159234

RESUMEN

BACKGROUND: Schistosomiasis is a relatively neglected parasitic disease that afflicts more than 250 million people worldwide, for which the control strategy relies mainly on mass treatment with the only available drug, praziquantel (PZQ). This approach is not sustainable and is a priority for developing novel drug candidates for the treatment and control of schistosomiasis. METHODOLOGYS/PRINCIPAL FINDINGS: In our previous study, we found that DW-3-15, a kind of PZQ derivative, could significantly downregulate the expression of the histone acetyltransferase of Schistosoma japonicum (SjHAT). In this study, several commercially available HAT inhibitors, A485, C646 and curcumin were screened in vitro to verify their antischistosomal activities against S. japonicum juveniles and adults. Parasitological studies and scanning electron microscopy were used to study the primary action characteristics of HAT inhibitors in vitro. Quantitative real-time PCR was employed to detect the mRNA level of SjHAT after treatment with different HAT inhibitors. Our results demonstrated that curcumin was the most effective inhibitor against both juveniles and adults of S. japonicum, and its schistosomicidal effects were time- and dose dependent. However, A485 and C646 had limited antischistosomal activity. Scanning electron microscopy demonstrated that in comparison with DW-3-15, curcumin caused similar tegumental changes in male adult worms. Furthermore, both curcumin and DW-3-15 significantly decreased the SjHAT mRNA level, and curcumin dose-dependently reduced the SjHAT expression level in female, male and juvenile worms. CONCLUSIONS: Among the three commercially available HATs, curcumin was the most potent against schistosomes. Both curcumin and our patent compound DW-3-15 markedly downregulated the expression of SjHAT, indicating that SjHAT may be a potential therapeutic target for developing novel antischistosomal drug candidates.

8.
Drug Metab Dispos ; 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39187385

RESUMEN

Organic anion transporting polypeptide (OATP) 1B1 and OATP1B3 are important hepatic transporters. We previously identified OATP1B3 being critically implicated in the disposition of abiraterone. We aimed to further investigate the effects of abiraterone on the activities of OATP1B1 and OATP1B3 utilizing a validated endogenous biomarker coproporphyrin I (CP-I). We utilized OATP1B-transfected cells to characterize the inhibitory potential of abiraterone against OATP1B-mediated uptake of CP-I. Inhibition constant (Ki) was incorporated into our physiologically based pharmacokinetic (PBPK) modeling to simulate the systemic exposures of CP-I among cancer populations receiving either our model-informed 500 mg or clinically approved 1000 mg abiraterone acetate (AA) dosage. Simulated data were compared with clinical CP-I concentrations determined among our 9 metastatic prostate cancer patients receiving 500 mg AA treatment. Abiraterone inhibited OATP1B3- but not OATP1B1-mediated uptake of CP-I in vitro, with an estimated Ki of 3.93 µM. Baseline CP-I concentrations were simulated to be 0.81 {plus minus} 0.26 ng/mL, and determined to be 0.72 {plus minus} 0.16 ng/mL among metastatic prostate cancer patients, both of which were higher than those observed for healthy subjects. PBPK simulations revealed an absence of OATP1B3-mediated interaction between abiraterone and CP-I. Our clinical observations confirmed that CP-I concentrations remained comparable to baseline levels up to 12 weeks post 500 mg AA treatment. Using CP-I as an endogenous biomarker, we identified the inhibition of abiraterone on OATP1B3 but not OATP1B1 in vitro, which was predicted and observed to be clinically insignificant. We concluded that the interaction risk between AA and substrates of OATP1Bs is low. Significance Statement We utilized the endogenous biomarker coproporphyrin I (CP-I) and identified abiraterone as a moderate inhibitor of organic anion transporting polypeptide (OATP) 1B3 in vitro. Subsequent physiologically based pharmacokinetic (PBPK) simulations and clinical observations suggested an absence of OATP1B-mediated interaction between abiraterone and CP-I among prostate cancer patients. This multi-pronged study concluded that the interaction risk between abiraterone acetate and substrates of OATP1Bs is low, demonstrating the application of PBPK-CP-I modelling in predicting OATP1B-mediated interaction implicating abiraterone.

9.
RSC Med Chem ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39185452

RESUMEN

Quorum sensing (QS) inhibition stands out as an innovative therapeutic strategy for combating infections caused by drug-resistant pathogens. In this study, we assessed the potential of 3-(2-isocyanobenzyl)-1H-indole derivatives as novel quorum sensing inhibitors (QSIs). Initial screenings of their QS inhibitory activities were conducted against Pseudomonas aeruginosa PAO1 and Chromobacterium violaceum CV026. Notably, six 3-(2-isocyanobenzyl)-1H-indole derivatives (4, 12, 25, 28, 32, and 33) exhibited promising QS, biofilms, and pyocyanin inhibitory activities under minimum inhibitory concentrations (MICs) against P. aeruginosa PAO1. Among them, 3-(2-isocyano-6-methylbenzyl)-1H-indole (IMBI, 32) emerged as the most promising candidate, demonstrating superior biofilm and pyocyanin inhibition. Further comprehensive studies revealed that derivative 32 at 25 µg mL-1 inhibited biofilm formation by 70% against P. aeruginosa PAO1, as confirmed by scanning electron microscopy (SEM). Additionally, derivative 32 substantially increased the susceptibility of mature biofilms, leading to a 57% destruction of biofilm architecture. In terms of interfering with virulence factors in P. aeruginosa PAO1, derivative 32 (25 µg mL-1) displayed remarkable inhibitory effects on pyocyanin, protease, and extracellular polysaccharides (EPS) by 73%, 51%, and 37%, respectively, exceeding the positive control resveratrol (RSV). Derivative 32 at 25 µg mL-1 also exhibited effective inhibition of swimming and swarming motilities. Moreover, it downregulated the expressions of QS-related genes, including lasI, lasR, rhlI, rhlR, pqsR, sdhB, sucD, sodB, and PA5439, by 1.82- to 10.87-fold. Molecular docking, molecular dynamics simulations (MD), and energy calculations further supported the stable binding of 32 to LasR, RhlI, RhlR, EsaL, and PqsR antagonizing the expression of QS-linked traits. Evaluation of the toxicity of derivative 32 on HEK293T cells via CCK-8 assay demonstrated low cytotoxicity. Overall, this study underscores the efficacy of derivative 32 in inhibiting virulence factors in P. aeruginosa. Derivative 32 emerges as a potential QSI for controlling P. aeruginosa PAO1 infections in vitro and an anti-biofilm agent for restoring or enhancing drug sensitivity in drug-resistant pathogens.

10.
EMBO Mol Med ; 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39122888

RESUMEN

Collecting duct carcinoma (CDC) is an aggressive rare subtype of kidney cancer with unmet clinical needs. Little is known about its underlying molecular alterations and etiology, primarily due to its rarity, and lack of preclinical models. This study aims to comprehensively characterize molecular alterations in CDC and identify its therapeutic vulnerabilities. Through whole-exome and transcriptome sequencing, we identified KRAS hotspot mutations (G12A/D/V) in 3/13 (23%) of the patients, in addition to known TP53, NF2 mutations. 3/13 (23%) patients carried a mutational signature (SBS22) caused by aristolochic acid (AA) exposures, known to be more prevalent in Asia, highlighting a geologically specific disease etiology. We further discovered that cell cycle-related pathways were the most predominantly dysregulated pathways. Our drug screening with our newly established CDC preclinical models identified a CDK9 inhibitor LDC000067 that specifically inhibited CDC tumor growth and prolonged survival. Our study not only improved our understanding of oncogenic molecular alterations of Asian CDC, but also identified cell-cycle machinery as a therapeutic vulnerability, laying the foundation for clinical trials to treat patients with such aggressive cancer.

11.
Am J Cancer Res ; 14(7): 3241-3258, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39113872

RESUMEN

Cancer is the disease that poses the greatest threat to human health today. Among them, hepatocellular carcinoma (HCC) is particularly prominent due to its high recurrence rate and extremely low five-year postoperative survival rate. In addition to surgical treatment, radiotherapy, chemotherapy, and immunotherapy are the main methods for treating HCC. Due to the natural drug resistance of chemoradiotherapy and targeted drugs, satisfactory results have not been achieved in terms of therapeutic efficacy and cost. AMP-Activated Protein Kinase (AMPK) is a serine/threonine protein kinase. It mainly coordinates the metabolism and transformation of energy between cells, which maintaining a balance between energy supply and demand. The processes of cell growth, proliferation, autophagy, and survival all involve various reaction of cells to energy changes. The regulatory role of AMPK in cellular energy metabolism plays an important role in the occurrence, development, treatment, and prognosis of HCC. Here, we reviewed the latest progress on the regulatory role of AMPK in the occurrence and development of HCC. Firstly, the molecular structure and activation mechanism of AMPK were introduced. Secondly, the emerging regulator related to AMPK and tumors were elaborated. Next, the multitasking roles of AMPK in the occurrence and development mechanism of HCC were discussed separately. Finally, the translational implications and the challenges of AMPK-targeted therapies for HCC treatment were elaborated. In summary, these pieces of information suggest that AMPK can serve as a promising specific therapeutic target for the treatment of HCC.

12.
Phytochemistry ; : 114246, 2024 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-39163914

RESUMEN

Centella asiatica (L.) Urban is a medical plant rich in triterpenoids, frequently used in Asia to treat skin conditions such as acne. To search for anti-photoaging agents, 16 known triterpenoids and five undescribed triterpenoids, including three ursane, one oleanane and one nor-ursane were isolated from the whole herb of C. asiatica. The structures and relative stereochemistry of these compounds were elucidated by detailed NMR spectra and HRESIMS. Compounds 1 and 2 were isomers of ursane-type and oleane-type triterpenes with rare aldehyde groups on C-23. Compound 4 was a unique example of a nor-ursane type triterpenoid. The Ultraviolet B (UVB) induced HaCaT cell damage model was used to measure the in vitro anti-photoaging activity of all 21 compounds. Twenty compounds significantly increased HaCaT viability and inhibited lactate dehydrogenase (LDH) release after UVB exposure. These findings highlight the protective effects of C. asiatica-derived triterpenoids against UVB damage and indicate their potential as natural agents that can protect the skin against photoaging.

13.
J Therm Biol ; 124: 103927, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39153259

RESUMEN

The sum of nonspecific physiological responses exhibited by mammals in response to the disruption of thermal balance caused by high-temperature environments is referred to as heat stress (HS). HS affects the normal development of mammalian oocyte and embryos and leads to significant economic losses. Therefore, it is of great importance to gain a deep understanding of the mechanisms underlying the effects of HS on oocyte and embryonic development and to explore strategies for mitigating or preventing its detrimental impacts in the livestock industry. This article provides an overview of the negative effects of HS on mammalian oocyte growth, granulosa cell maturation and function, and embryonic development. It summarizes the mechanisms by which HS affects embryonic development, including generation of reactive oxygen species (ROS), endocrine disruption, the heat shock system, mitochondrial autophagy, and molecular-level alterations. Furthermore, it discusses various measures to ameliorate the effects of HS, such as antioxidant use, enhancement of mitochondrial function, gene editing, cultivating varieties possessing heat-resistant genes, and optimizing the animals'rearing environment. This article serves as a valuable reference for better understanding the relationship between HS and mammalian embryonic development as well as for improving the development of mammalian embryos and economic benefits under HS conditions in livestock production.

14.
Langmuir ; 40(33): 17796-17806, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39121350

RESUMEN

Calcination of MgCO3 is an important industrial reaction, but it causes significant and unfavorable CO2 production. Calcination in a reducing green hydrogen atmosphere can substantially reduce CO2 release and produce high value-added products such as CO or hydrocarbons, but the mechanism is still unclear. Here, the in situ transformation process of MgCO3 interacting with hydrogen and the specific formation mechanism of the high value-added products are thoroughly investigated based on reaction thermodynamic, ab initio molecular dynamics (AIMD) simulations, and density functional theory (DFT) calculations. The reaction thermodynamic parameters of MgCO3 coupled with hydrogen to produce CO or methane are calculated, revealing that increasing and decreasing the thermal reductive decomposition temperature favors the production of CO and methane, respectively. Kinetically, the energy barriers of each possible production pathway for the dominant products CO and methane are further calculated in conjunction with the AIMD simulation results of the transformation process. The results suggest that CO is produced via the MgO catalytic-carboxyl pathway (CO2*→ COOH*trans→ COOH*cis→ CO*→ CO), which is autocatalyzed by MgO derived from the thermal reductive decomposition of MgCO3. For the mechanism of methane formation, it prefers to be produced by the stepwise interaction of carbonates in the MgCO3 laminates with hydrogen adsorbed on their surfaces (direct conversion pathway: sur-O-CO → sur-O-HCO → sur-O-HCOH → sur-O-HC → sur-O-CH2 → sur-O-CH3 → sur-O + CH4*).

15.
Huan Jing Ke Xue ; 45(8): 4932-4945, 2024 Aug 08.
Artículo en Chino | MEDLINE | ID: mdl-39168709

RESUMEN

Methane (CH4) and nitrous oxide (N2O) are concerning greenhouse gases. Urban rivers have been important emission sources of CH4 and N2O in recent years. It is meaningful for city greenhouse gas reduction to provide a systematic analysis of spatiotemporal characteristics, mechanisms, and influencing factors of the production and emission of CH4 and N2O from urban rivers. This study combed measured data of urban river CH4 and N2O dissolution concentrations and emission fluxes from related literature published in the past 20 years and also concluded the spatiotemporal characteristics of urban river CH4 and N2O emissions. This study estimated that CH4 and N2O emissions (expressed by CO2-eq) from urban rivers in Beijing were 234.63 and 59.53 Gg CO2-eq in 2018, whereas CH4 and N2O emissions (expressed by CO2-eq) from urban rivers in Shanghai were 159.86 and 260.24 Gg CO2-eq in 2018, respectively. These results demonstrated that urban rivers have become important CH4 and N2O emission sources. This study summarized the production/consumption processes and import/export pathways of CH4 and N2O in urban rivers. What is more, this study discussed the main influencing factors of urban river CH4 and N2O production and emissions from the perspectives of river environmental conditions and urbanization effects. At last, the present work prospected the future research trends of urban river CH4 and N2O emissions and provides urban rivers with scientific support for greenhouse gas reduction.

16.
Quant Imaging Med Surg ; 14(8): 5774-5788, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39144033

RESUMEN

Background: Amyotrophic lateral sclerosis (ALS)-related white-matter microstructural abnormalities have received considerable attention; however, gray-matter structural abnormalities have not been fully elucidated. This study aimed to evaluate cortical microstructural abnormalities in ALS and determine their association with disease severity. Methods: This study included 34 patients with ALS and 30 healthy controls. Diffusion-weighted data were used to estimate neurite orientation dispersion and density imaging (NODDI) parameters, including neurite density index (NDI) and orientation dispersion index (ODI). We performed gray matter-based spatial statistics (GBSS) in a voxel-wise manner to determine the cortical microstructure difference. We used the revised ALS Functional Rating Scale (ALSFRS-R) to assess disease severity and conducted a correlation analysis between NODDI parameters and ALSFRS-R. Results: In patients with ALS, the NDI reduction involved several cortical regions [primarily the precentral gyrus, postcentral gyrus, temporal cortex, prefrontal cortex, occipital cortex, and posterior parietal cortex; family-wise error (FWE)-corrected P<0.05]. ODI decreased in relatively few cortical regions (including the precentral gyrus, postcentral gyrus, prefrontal cortex, and inferior parietal lobule; FWE-corrected P<0.05). The NDI value in the left precentral and postcentral gyrus was positively correlated with the ALS disease severity (FWE-corrected P<0.05). Conclusions: The decreases in NDI and ODI involved both motor-related and extra-motor regions and indicated the presence of gray-matter microstructural impairment in ALS. NODDI parameters are potential imaging biomarkers for evaluating disease severity in vivo. Our results showed that GBSS is a feasible method for identifying abnormalities in the cortical microstructure of patients with ALS.

17.
R Soc Open Sci ; 11(8): 240284, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39144495

RESUMEN

Advanced in vitro culture systems have emerged as alternatives to animal testing and traditional cell culture methods in biomedical research. Polydimethylsiloxane (PDMS) is frequently used in creating sophisticated culture devices owing to its elastomeric properties, which allow mechanical stretching to simulate physiological movements in cell experiments. We introduce a straightforward method that uses three types of commercial tape-generic, magic and masking-to fabricate PDMS membranes with microscale thicknesses (47.2 µm for generic, 58.1 µm for magic and 89.37 µm for masking) in these devices. These membranes are shaped as the bases of culture wells and can perform cyclic radial movements controlled via a vacuum system. In experiments with A549 cells under three mechanical stimulation conditions, we analysed transcriptional regulators responsive to external mechanical stimuli. Results indicated increased nuclear yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) activity in both confluent and densely packed cells under cyclically mechanical strains (Pearson's coefficient (PC) of 0.59 in confluent and 0.24 in dense cells) compared with static (PC = 0.47 in confluent and 0.13 in dense) and stretched conditions (PC = 0.55 in confluent and 0.20 in dense). This technique offers laboratories without microfabrication capabilities a viable option for exploring cellular behaviour under dynamic mechanical stimulation using PDMS membrane-equipped devices.

18.
Water Res ; 264: 122240, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39146854

RESUMEN

The release of rubber-derived chemicals (RDCs) in road surface runoff has received significant attention. Urban surface runoff is often the confluence of stormwater runoff from specific areas. However, the impact of precipitation on RDCs contamination in confluent stormwater runoff and receiving watersheds remains poorly understood. Herein, we investigated the profiles of RDCs and their transformation products in confluent stormwater runoff and receiving rivers affected by precipitation events. The results showed that 34 RDCs are ubiquitously present in confluent stormwater runoff and surface water, with mean concentrations of 1.03-2749 and 0.28-436 ng/L, respectively. The most dominant target compounds in each category were N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), 6PPD-quinone, 2-benzothiazolol, and 1,3-diphenylguanidine. Total RDCs concentrations in confluent stormwater runoff decreased spatially from industrial areas to business districts to college towns. A significant decrease in RDCs levels in surface water after rainfall was observed (P < 0.01), indicating that precipitation contributes to alleviating RDCs pollution in receiving watersheds. To our knowledge, this is the first report of N,N'-ditolyl-p-phenylenediamine quinone (DTPD-Q) levels in surface waters in China. The annual mass load of ∑RDCs reached 72,818 kg/y in confluent stormwater runoff, while 38,799 kg/y in surface water. The monitoring of confluent stormwater runoff is an efficient measure for predicting contamination loads from RDCs in rivers. Risk assessment suggested that most RDCs posed at least medium risks to aquatic organisms, especially 6PPD-quinone. The findings help to understand the environmental fate and risks of RDCs in the confluent stormwater runoff and receiving environments after precipitation events.

19.
Shanghai Kou Qiang Yi Xue ; 33(2): 123-129, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-39005086

RESUMEN

PURPOSE: To investigate the effect of Morinda officinalis polysaccharides(MOP) on the expression of fibronectin(FN) and fibronectin containing extra domain A(FN-EDA) in inflammatory periodontal ligament fibroblasts. METHODS: Thirty six rats were randomly divided into a control group(n=12) and a model group (n=24). The model group used orthodontic wire ligation to establish periodontitis. After three weeks, 6 rats from each group were selected and confirmed by Micro-CT to complete the modeling. The remaining rats in the model group were randomly divided into periodontitis group, normal saline(NS) group, and MOP group. In the MOP group, MOP (200 mg/kg for 3 d, 50 µL for 4 weeks) was injected into the palatal side of the left maxillary first molar of the rats. In the NS group, same volume of NS was injected, and no treatment was performed in the periodontitis group. The left maxillary tissue of rats were taken and the pathological changes of periodontal tissue were observed by H-E staining. The expression of FN and FN-EDA was detected by immunohistochemistry. Periodontal ligament fibroblasts were cultured in vitro, the effect of MOP on cell activity detected by CCK-8. The fourth generation cells were divided into control group, inflammation group (10 mg/mL lipopolysaccharide), and experimental group (12.5 µg/mL MOP, 12.5 µg/mL MOP+10 mg/mL lipopolysaccharide). The expression of FN and FN-EDA was detected by qRT-PCR and Western blot. The data were statistically analyzed using Prism 8.0 software package. RESULTS: In vivo experiments, the expression of FN-EDA in the MOP group was significantly lower than that in the periodontitis group and NS group(P<0.05), and the infiltration of inflammatory cells was reduced. However, there was no significant difference in the expression of FN in each group. In vitro experiments, compared with the control group, the expression of FN-EDA mRNA and protein in the inflammation group was significantly increased(P<0.000 1). MOP significantly reduced the expression of FN-EDA in inflammatory cells, but had no significant effect on FN expression. CONCLUSIONS: With increased expression of FN-EDA in inflammatory periodontal ligament tissues and cells, MOP may play a role in inhibiting inflammation by down-regulating FN-EDA.


Asunto(s)
Fibroblastos , Fibronectinas , Morinda , Ligamento Periodontal , Polisacáridos , Animales , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Polisacáridos/farmacología , Ligamento Periodontal/efectos de los fármacos , Ligamento Periodontal/metabolismo , Ligamento Periodontal/citología , Ratas , Morinda/química , Fibronectinas/metabolismo , Fibronectinas/genética , Periodontitis/tratamiento farmacológico , Periodontitis/metabolismo , Inflamación/tratamiento farmacológico , Ratas Sprague-Dawley
20.
Angew Chem Int Ed Engl ; : e202411166, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008335

RESUMEN

Molecular editing promises to facilitate the rapid diversification of complex molecular architectures by rapidly and conveniently altering core frameworks. This approach has the potential to accelerate both drug discovery and total synthesis. In this study, we present a novel protocol for the molecular editing of pyrroles. Initially, N-Boc pyrroles and alkynes are converted into N-bridged compounds through a Diels-Alder reaction. These compounds then undergo deprotection of the Boc group, nitrosylation, and cheletropic N2O extrusion to yield benzene or naphthalene products. By using benzyne as a substrate, this method can be conceptually viewed as a fusion of skeletal editing of the pyrrole ring and site-selective peripheral editing of the benzene ring. Furthermore, this proof-of-concept protocol has demonstrated its potential to transform the (hetero)arene motif from commercially available drugs, offering the possibility of generating new biologically active compounds.

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