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1.
RSC Adv ; 14(21): 15071-15084, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38720976

RESUMEN

The alkane cracking mechanism has been a subject of intense scrutiny, with carbonium and free radical mechanisms being two well-established pathways which correlate to solid acid catalysis and thermal cracking, respectively. However, despite an understanding of these two mechanisms, certain intricacies remain unexplored, especially when it comes to alternative reaction routes over solid base materials. This gap in the knowledge hinders optimization of the desired product selectivity of alkane cracking processes. In this work, solid superbases were first prepared by impregnation of NaNO3 on MgO. The Na/MgO catalysts were characterized by XRD, BET, XPS and CO2-TPD techniques. To investigate the role of solid base materials, propane cracking was conducted over MgO and Na/MgO. SiO2 was chosen as a representative of thermal cracking. Na/MgO showed better selectivity for light olefins than MgO or SiO2. Ethylene and light olefin selectivity could reach about 65.8% and 91.7%, respectively. Meanwhile, in terms of Na/MgO, the ratio of ethylene selectivity and propylene selectivity is greater than 2, exhibiting the advantage of selectivity for ethylene, which is obviously different from MgO and SiO2. Propane cracking over Na/MgO with different loading amounts of NaNO3 was investigated further. The conversion rates of the samples presented a "volcano curve" with increasing Na content. Furthermore, DFT calculation showed that the base-catalyzed process of the propane cracking reaction follows a carbanion mechanism. The better product distribution and stronger surface base sites can be ascribed to charge transfer arising from the loading of NaNO3.

2.
Int J Ophthalmol ; 17(3): 435-443, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721521

RESUMEN

AIM: To investigate the underlying mechanism of dry environment (autumn dryness) affecting the lacrimal glands in rats. METHODS: Twenty Sprague-Dawley rats were randomly divided into two groups. The rats were fed in specific pathogen free environment as the control group (n=10), and the rats fed in dry environment as the dryness group (n=10). After 24d, lacrimal glands were collected from the rats. The tissues morphology was observed by hematoxylin-eosin (HE) staining. Tandem mass tags (TMT) quantitative proteomics analysis technology was used to screen the differential expressed proteins of lacrimal glands between the two groups, then bioinformatics analysis was performed. Further, the immunohistochemical (IHC) method was used to verify the target proteins. RESULTS: In dryness group, the lacrimal glands lobule atrophied, the glandular cavities enlarged, the sparse nuclear distribution and scattered inflammatory infiltration between the acinus were observed. The proteomics exhibited that a total of 195 up-regulated and 236 down-regulated differential expressed proteins screened from the lacrimal glands of rats. It was indicated that the biological processes (BP) of differential expressed proteins mainly included cell processes and single BP. The cellular compositions of differential expressed proteins mainly located in cells, organelles. The molecular functions of differential expressed proteins mainly included binding, catalytic activity. Moreover, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that the differential expressed proteins mainly involved lysosome, complement and coagulation cascade, and ribosome pathway. The IHC result verified that the up-regulated expression proteins of Protein S100A9 (S100A9), Annexin A1 (Anxa1), and Clusterin (Clu) in lacrimal glands of rats in dryness group were higher than control group. CONCLUSION: The up-regulated expression proteins of S100A9, Anxa1, and Clu may be the potential mechanisms of dry eye symptoms caused by dry environment. This study provides clues of dry environments causing eye-related diseases for further studies.

3.
Plant Physiol Biochem ; 211: 108679, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38714127

RESUMEN

Cold stress is a limiting stress factor that limits plant distribution and development; however, polyploid plants have specific characteristics such as higher resistance to abiotic stress, especially cold stress, that allow them to overcome this challenge. The cultivated cultivar Ziziphus jujuba Mill. 'Yueguang' (YG) and its autotetraploid counterpart 'Hongguang' (HG) exhibit differential cold tolerance. However, the underlying molecular mechanism and methods to enhance their cold tolerance remain unknown. Anatomical structure and physiological analysis indicated YG had a higher wood bark ratio, and xylem ratio under cold treatment compared to HG. However, the half-lethal temperature (LT50), cortex ratio, and malondialdehyde (MDA) content were significantly decreased in YG than HG, which indicated YG was cold tolerant than HG. Transcriptome analysis showed that 2084, 1725, 2888, and 2934 differentially expressed genes (DEGs) were identified in HC vs YC, H20 vs Y20, Y20 vs YC, and H20 vs HC treatment, respectively. Meanwhile, KEGG enrichment analysis of DEGs showed that several metabolic pathways, primarily plant hormone signal transduction and the MAPK signaling pathway, were involved in the differential regulation of cold tolerance between YG and HG. Furthermore, exogenous abscisic acid (ABA) and brassinolide (BR) treatments could improve their cold tolerance through increased SOD and POD activities, decreased relative electrical conductivity, and MDA content. All of these findings suggested that plant hormone signal transduction, particularly ABA and BR, might have an important role in the regulation of differential cold tolerance between YG and HG, laying the foundation for further improving cold tolerance in jujube and examining the molecular mechanisms underlying differences in cold tolerance among different ploidy cultivars.

4.
Am J Chin Med ; : 1-22, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38716616

RESUMEN

In recent years, due to advancements in medical conditions and the development of scientific research, the fundamental research of TCM antitumor treatments has progressed from the cellular level to the molecular and genetic levels. Previous studies have demonstrated the significant role of traditional Chinese medicine (TCM) in antitumor therapy through various mechanisms and pathways. Its mechanism of action is closely associated with cancer biology across different stages. This includes inhibiting tumor cell proliferation, blocking invasion and metastasis to surrounding tissues, inducing tumor cell apoptosis, inhibiting tumor angiogenesis, regulating immune function, maintaining genome stability, preventing mutation, and regulating cell energy metabolism. The use of TCM for eliciting antitumor effects not only has a good therapeutic effect and low side effects, it also provides a solid theoretical basis for clinical treatment and medication. This paper reviews the mechanism of the antitumor effects of TCM based on tumor characteristics. Through our review, we found that TCM not only directly inhibits tumors, but also enhances the body's immunity, thereby indirectly inducing an antitumor effect. This function aligns with the TCM theory of "strengthening the body's resistance to eliminate pathogenic factors". Furthermore, TCM will play a significant role in tumor treatment in clinical settings.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38717638

RESUMEN

BACKGROUND: Cardiac hypertrophy is the common pathological process of multiple cardiovascular diseases. However, the molecular mechanisms of cardiac hypertrophy are unclear. Long non-coding RNA (lncRNA), a newly discovered type of transcript that has been demonstrated to function as crucial regulators in the development of cardiovascular diseases. This study revealed a novel regulatory pathway of lncRNA in cardiac hypertrophy. METHODS: The cardiac hypertrophy models were established by transverse aortic constriction (TAC) in mice and angiotensin II (Ang II) in HL-1 cardiomyocytes. Adeno-associated virus 9 (AAV9) in vivo and lncRNA Gm15834 and shRNA plasmids in vitro were used to overexpress and knock down lncRNA Gm15834. The myocardial tissue structure, cardiomyocyte area, cardiac function, protein expressions, and binding of lncRNA Gm15834 and Src-associated substrate during mitosis of 68 KDa (Sam68) were detected by hematoxylin and eosin (HE) staining, immunofluorescence staining, echocardiography, western blot and RNA immunoprecipitation (RIP), respectively. RESULTS: In cardiac hypertrophy models, inhibiting lncRNA Gm15834 could decrease Sam68 expression and nuclear factor kappa-B (NF-κB) mediated inflammatory activities in vivo and in vitro, but overexpressing lncRNA Gm15834 showed the opposite results. RIP experiments validated the binding activities between lncRNA Gm15834 and Sam68. Overexpression of Sam68 could counteract the anti-hypertrophy effects of lncRNA Gm15834 knockdown. Meanwhile, in vivo inhibition of lncRNA Gm15834 could inhibit Sam68 expression, reduce NF-κB mediated inflammatory activity and attenuate cardiac hypertrophy. CONCLUSION: Our study revealed a novel regulatory axis of cardiac hypertrophy, which comprised lncRNA Gm15834/Sam68/NF-κB/inflammation, shedding a new light for identifying therapy target of cardiac hypertrophy in clinic.

6.
World J Diabetes ; 15(3): 502-518, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38591083

RESUMEN

BACKGROUND: Jianpi Gushen Huayu Decoction (JPGS) has been used to clinically treat diabetic nephropathy (DN) for many years. However, the protective mechanism of JPGS in treating DN remains unclear. AIM: To evaluate the therapeutic effects and the possible mechanism of JPGS on DN. METHODS: We first evaluated the therapeutic potential of JPGS on a DN mouse model. We then investigated the effect of JPGS on the renal metabolite levels of DN mice using non-targeted metabolomics. Furthermore, we examined the effects of JPGS on c-Jun N-terminal kinase (JNK)/P38-mediated apoptosis and the inflammatory responses mediated by toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB)/NOD-like receptor family pyrin domain containing 3 (NLRP3). RESULTS: The ameliorative effects of JPGS on DN mice included the alleviation of renal injury and the control of inflammation and oxidative stress. Untargeted metabolomic analysis revealed that JPGS altered the metabolites of the kidneys in DN mice. A total of 51 differential metabolites were screened. Pathway analysis results indicated that nine pathways significantly changed between the control and model groups, while six pathways significantly altered between the model and JPGS groups. Pathways related to cysteine and methionine metabolism; alanine, tryptophan metabolism; aspartate and glutamate metabolism; and riboflavin metabolism were identified as the key pathways through which JPGS affects DN. Further experimental validation showed that JPGS treatment reduced the expression of TLR4/NF-κB/NLRP3 pathways and JNK/P38 pathway-mediated apoptosis related factors. CONCLUSION: JPGS could markedly treat mice with streptozotocin (STZ)-induced DN, which is possibly related to the regulation of several metabolic pathways found in kidneys. Furthermore, JPGS could improve kidney inflammatory responses and ameliorate kidney injuries in DN mice via the TLR4/NF-κB/NLRP3 pathway and inhibit JNK/P38 pathway-mediated apoptosis in DN mice.

7.
J Endovasc Ther ; : 15266028241245325, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38616626

RESUMEN

PURPOSE: The purpose was to evaluate the clinical outcomes of a dedicated venous stent with the tripartite composite segments for the treatment of iliofemoral venous obstruction (IVO) in a mixed cohort of nonthrombotic iliac vein lesion (NIVL) and post-thrombotic syndrome (PTS) over a period of 12 months. METHODS: The Grency Trial is a prospective, multicenter, single-arm, open-label, pivotal study, which was conducted at 18 large tertiary hospitals in China from August 2019 to October 2020. A total of 133 hospitalized patients were screened and 110 patients with clinical, etiology, anatomical, and pathophysiology clinical class (CEAP) clinical grade C>3 and iliac vein stenosis >50% or occlusion, including 72 patients with NIVL and 38 patients with PTS, were implanted with Grency venous stents. Primary endpoint was stent patency at 12 months follow-up, and secondary outcomes were technical success; improvement in venous clinical severity score (VCSS) at 3, 6, and 12 month follow-up; and rates of clinical adverse events. RESULTS: Among 110 patients who were implanted with Grency venous stents, 107 patients completed the 12 month follow-up. All 129 stents were successfully implanted in 110 limbs. Twelve-month primary patency rate was 94.39% [95% confidence interval [CI]=88.19%-97.91%] overall, and 100% [94.94%-100%] and 83.33% [67.19%-93.63%] in the NIVL and PTS subgroups, respectively. Venous clinical severity score after iliac vein stenting improved significantly up to 12 months follow-up. There were 3 early major adverse events (1 intracerebral hemorrhage and 2 stent thrombosis events related to anticoagulation therapy), and 7 late major adverse events (1 cardiovascular death, 1 intracranial hemorrhage with uncontrolled hypertension, and 5 in-stent restenosis cases without stent fractures or migration). CONCLUSIONS: The Grency venous stent system appeared excellent preliminary safe and effective for IVO treatment. Further large-scale studies with longer-term follow-up are needed to evaluate long-term patency and durability of stent. CLINICAL IMPACT: The design of venous stents for iliofemoral venous obstruction (IVO) must address engineering challenges distinct from those encountered in arterial stenting. The Grency venous stent, a nitinol self-expanding stent specifically tailored for IVO, features a composite structure designed to meet the stent requirements of various iliac vein segments. The Grency Trial is a prospective, multicenter, single-arm, open-label pivotal study aimed at evaluating the efficacy and safety of the Grency stent system. Following a 12-month follow-up period, the Grency venous stent system has demonstrated both safety and efficacy in treating iliofemoral venous outflow obstruction.

8.
Vascular ; : 17085381241247613, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38631687

RESUMEN

OBJECTIVE: To review our multi-institutional experience with endovascular therapy for right subclavian artery occlusive disease and to evaluate the long-term outcomes. METHODS: We retrospectively evaluated all patients with right subclavian artery stenosis and occlusive disease who underwent endovascular therapy between March 2014 and September 2022 at two institutions. Patient baseline demographics, lesion characteristics, treatment strategies, and in-hospital and follow-up outcomes were prospectively collected and retrospectively analyzed. RESULTS: Between March 2014 and September 2022, 73 patients underwent endovascular treatment at the two institutions. The dominant cause of lesions in this cohort was atherosclerosis. Three different types of lesions were summarized, and the corresponding endovascular strategies were performed. 66 patients (90.4%) underwent successful endovascular treatment, and 62 patients (84.9%) underwent balloon-expandable stent deployment. The mean perioperative in-hospital stay was 4.0 days (range, 3-6 days). Two patients died due to myocardial infarction, and one died of cerebral hemorrhage resulting from a traffic accident within 30 days of the intervention. The median follow-up time was 31.6 months (range, 12-96 months). No complications, including death, stroke, stent fractures, or migration, were noted in any patient during the follow-up period. The overall complication rate was 7/73 (9.6%), and 5/7 (6.9%) of the complications required reintervention. CONCLUSIONS: Endovascular treatment of right subclavian artery lesions is safe, effective, and technically achievable. The reasonable use of balloon-expandable stents can achieve satisfactory outcomes with accurate orientation and promising patency.

9.
J Virol ; 98(5): e0192523, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38624230

RESUMEN

Recurrent respiratory papillomatosis (RRP) is a rare benign tumor caused mainly by the infection of the respiratory tract epithelial cells by the human papillomavirus (HPV) type 6/11. However, the specific mechanisms underlying the inhibition of the host's innate immune response by HPV remain unclear. For this purpose, we employed single-cell RNA sequencing to analyze the states of various immune cells in RRP samples post-HPV infection and utilized a cellular model of HPV infection to elucidate the mechanisms by which HPV evades the innate immune system in RRP. The results revealed distinct immune cell heterogeneity in RRP and demonstrated that HPV11 E7 can inhibit the phosphorylation of the stimulator of interferon genes protein, thereby circumventing the body's antiviral response. In vitro co-culture experiments demonstrated that stimulation of macrophages to produce interferon-beta induced the death of HPV-infected epithelial cells, also reducing HPV viral levels. In summary, our study preliminarily identifies the potential mechanisms by which HPV evades the host's antiviral immune response, as well as the latent antiviral functions exhibited by activated macrophages. This research serves as an initial exploration of antiviral immune evasion in RRP, laying a solid foundation for investigating immunotherapeutic approaches for the disease.IMPORTANCESurgical tumor reduction is the most common treatment for recurrent respiratory papillomatosis (RRP). One of the characteristics of RRP is its persistent recurrence, and multiple surgeries are usually required to control the symptoms. Recently, some adjuvant therapies have shown effectiveness, but none of them can completely clear human papillomavirus (HPV) infection, and thus, a localized antiviral immune response is significant for disease control; after all, HPV infection is limited to the epithelium. Inhibition of interferon-beta (IFN-ß) secretion by HPV11 E7 viral proteins in epithelial cells by affecting stimulator of interferon genes phosphorylation may account for the persistence of low-risk HPV replication in the RRP. Moreover, suppression of the IFN-I pathway in RRP cell types might provide clues regarding the hyporeactive function of local immune cells. However, activation of macrophage groups to produce IFN-ß can still destroy HPV-infected cells.


Asunto(s)
Papillomavirus Humano 11 , Inmunidad Innata , Interferón beta , Macrófagos , Proteínas de la Membrana , Infecciones por Papillomavirus , Infecciones del Sistema Respiratorio , Interferón beta/metabolismo , Interferón beta/inmunología , Interferón beta/genética , Humanos , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/virología , Papillomavirus Humano 11/genética , Papillomavirus Humano 11/inmunología , Infecciones del Sistema Respiratorio/virología , Infecciones del Sistema Respiratorio/inmunología , Macrófagos/inmunología , Macrófagos/virología , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Femenino , Células Epiteliales/virología , Células Epiteliales/inmunología , Evasión Inmune , Proteínas E7 de Papillomavirus/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/inmunología , Masculino , Adulto
10.
Sci Total Environ ; 930: 172722, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38677441

RESUMEN

Inland waters (IW), estuarine areas (EA), and offshore areas (OA) function as aquatic systems in which the transport of carbon components results in the release of greenhouse gases (GHGs). Interconnected subsystems exhibit a greater greenhouse effect than individual systems. Despite this, there is a lack of research on how carbon loading and its components impact GHG emissions in various aquatic systems. In this study, we analyzed 430 aquatic sites to explore trade-off mechanisms among dissolved organic carbon (DOC), particulate organic carbon, dissolved inorganic carbon (DIC), and GHGs. The results revealed that IW emerged as the most significant GHG source, possessing a comprehensive global warming potential (GWP) of 0.78 ± 0.08 (10-2 Pg CO2-ep ha-1 year-1) for combined carbon dioxide, methane, and nitrous oxide. This surpassed the cumulative potentials of EA and OA (0.35 ± 0.05 (10-2 Pg CO2-ep ha-1 year-1)). Additionally, structural equation modeling indicated that GHG emissions resulted from a combination of carbon component loading and environmental factors. DOC exhibited a positive correlation with GWPs when influenced by biodegradable DOC. Total alkalinity and pH influenced DIC, leading to elevated pCO2 in aquatic systems, thereby enhancing GWPs. Predictive modeling using backpropagation artificial neural networks (BP-ANN) for GWPs, incorporating carbon components and environmental factors, demonstrated a good fit (R2 = 0.6078, RMSEaverage = 0.069, p > 0.05) between observed and predicted values. Enhancing the estimation of aquatic region feedback to GHG changes was achieved by incorporating corresponding water quality parameters. In summary, this study underscores the pivotal role of carbon components and environmental factors in aquatic regions for GHG emissions. The application of BP-ANN to estimate greenhouse effects from aquatic regions is highlighted, providing theoretical and experimental support for future advancements in monitoring and developing policies concerning the influence of water quality on GHG emissions.

11.
J Vasc Surg ; 2024 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-38621637

RESUMEN

OBJECTIVE: As it remains unclear whether there are sex-based differences in clinical outcomes after thoracic endovascular aortic repair (TEVAR), this meta-analysis aimed to evaluate differences in early outcomes and overall survival between female and male patients who underwent TEVAR. METHODS: The PubMed, Embase, Web of Science, and Cochrane Central databases were searched for eligible studies published through June 10, 2023, that reported sex-based differences in clinical outcomes after TEVAR. The primary outcome was operative mortality; second outcomes included stroke, spinal cord ischemia, acute kidney injury, hospital length of stay, and overall survival. Patient characteristics, operative data, and early outcomes were aggregated using the random-effects model, presenting pooled risk ratio (RR) or standardized mean difference along with their corresponding 95% confidence intervals (CIs). Overall survival was assessed by reconstructing individual patient data to generate sex-specific pooled Kaplan-Meier curves. This study was registered in PROSPERO (CRD42023426069). RESULTS: Of the 1785 studies retrieved, 14 studies met all eligibility criteria, encompassing a total of 17,374 patients, comprising 5026 female and 12,348 male patients. Female patients were older, had a smaller maximum aortic diameter, had lower rates of smoking and coronary artery disease, and had higher rates of anemia. Intraoperatively, female patients were more likely to use iliac conduits and require blood transfusions. There were no sex-based differences in operative mortality (RR: 1.12, 95% CI: 0.90-1.40; P = .309), stroke (RR: 1.14, 95% CI: 0.95-1.38; P = .165), spinal cord ischemia (RR: 1.33, 95% CI: 0.83-2.14; P = .234), acute kidney injury (RR: 0.78, 95% CI: 0.52-1.17; P = .228), and hospital length of stay (standardized mean difference: 0.09, 95% CI: -0.03 to 0.20; P = .141). Pooled Kaplan-Meier estimates showed a worse overall survival in female patients compared with male patients (87.2% vs 89.8% at 2 years, log-rank P = .001). CONCLUSIONS: Among patients treated by TEVAR, female sex was not associated with increased risk of operative mortality or major morbidity. However, female patients exhibited a lower overall survival after TEVAR compared with male patients.

12.
Free Radic Biol Med ; 219: 153-162, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38657753

RESUMEN

The anemia of inflammation (AI) is characterized by the presence of inflammation and abnormal elevation of hepcidin. Accumulating evidence has proved that Rocaglamide (RocA) was involved in inflammation regulation. Nevertheless, the role of RocA in AI, especially in iron metabolism, has not been investigated, and its underlying mechanism remains elusive. Here, we demonstrated that RocA dramatically suppressed the elevation of hepcidin and ferritin in LPS-treated mice cell line RAW264.7 and peritoneal macrophages. In vivo study showed that RocA can restrain the depletion of serum iron (SI) and transferrin (Tf) saturation caused by LPS. Further investigation showed that RocA suppressed the upregulation of hepcidin mRNA and downregulation of Fpn1 protein expression in the spleen and liver of LPS-treated mice. Mechanistically, this effect was attributed to RocA's ability to inhibit the IL-6/STAT3 pathway, resulting in the suppression of hepcidin mRNA and subsequent increase in Fpn1 and TfR1 expression in LPS-treated macrophages. Moreover, RocA inhibited the elevation of the cellular labile iron pool (LIP) and reactive oxygen species (ROS) induced by LPS in RAW264.7 cells. These findings reveal a pivotal mechanism underlying the roles of RocA in modulating iron homeostasis and also provide a candidate natural product on alleviating AI.


Asunto(s)
Hepcidinas , Homeostasis , Interleucina-6 , Hierro , Lipopolisacáridos , Receptores de Transferrina , Factor de Transcripción STAT3 , Hepcidinas/metabolismo , Hepcidinas/genética , Animales , Ratones , Hierro/metabolismo , Células RAW 264.7 , Receptores de Transferrina/metabolismo , Receptores de Transferrina/genética , Lipopolisacáridos/farmacología , Interleucina-6/metabolismo , Interleucina-6/genética , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/genética , Especies Reactivas de Oxígeno/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Inflamación/metabolismo , Inflamación/genética , Inflamación/patología , Transducción de Señal/efectos de los fármacos , Anemia/metabolismo , Anemia/genética , Anemia/tratamiento farmacológico , Anemia/patología , Ferritinas/metabolismo , Ferritinas/genética , Masculino , Hígado/metabolismo , Hígado/patología , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Proteínas de Transporte de Catión
13.
Front Plant Sci ; 15: 1294895, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38645388

RESUMEN

Livestock presence impacts plant biodiversity (species richness) in grassland ecosystems, yet extent and direction of grazing impacts on biodiversity vary greatly across inter-annual periods. In this study, an 8-year (2014-2021) grazing gradient experiment with sheep was conducted in a semi-arid grassland to investigate the impact of grazing under different precipitation variability on biodiversity. The results suggest no direct impact of grazing on species richness in semi-arid Stipa grassland. However, increased grazing indirectly enhanced species richness by elevating community dominance (increasing the sheltering effect of Stipa grass). Importantly, intensified grazing also regulates excessive community biomass resulting from increased inter-annual wetness (SPEI), amplifying the positive influence of annual humidity index on species richness. Lastly, we emphasize that, in water-constrained grassland ecosystems, intra-annual precipitation variability (PCI) was the most crucial factor driving species richness. Therefore, the water-heat synchrony during the growing season may alleviate physiological constraints on plants, significantly enhancing species richness as a result of multifactorial interactions. Our study provides strong evidence for how to regulate grazing intensity to increase biodiversity under future variable climate patterns. We suggest adapting grazing intensity according to local climate variability to achieve grassland biodiversity conservation.

14.
Nat Commun ; 15(1): 2951, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38580660

RESUMEN

Hepatitis B virus is a globally distributed pathogen and the history of HBV infection in humans predates 10000 years. However, long-term evolutionary history of HBV in Eastern Eurasia remains elusive. We present 34 ancient HBV genomes dating between approximately 5000 to 400 years ago sourced from 17 sites across Eastern Eurasia. Ten sequences have full coverage, and only two sequences have less than 50% coverage. Our results suggest a potential origin of genotypes B and D in Eastern Asia. We observed a higher level of HBV diversity within Eastern Eurasia compared to Western Eurasia between 5000 and 3000 years ago, characterized by the presence of five different genotypes (A, B, C, D, WENBA), underscoring the significance of human migrations and interactions in the spread of HBV. Our results suggest the possibility of a transition from non-recombinant subgenotypes (B1, B5) to recombinant subgenotypes (B2 - B4). This suggests a shift in epidemiological dynamics within Eastern Eurasia over time. Here, our study elucidates the regional origins of prevalent genotypes and shifts in viral subgenotypes over centuries.


Asunto(s)
Virus de la Hepatitis B , Migración Humana , Humanos , Virus de la Hepatitis B/genética , Filogenia , Genotipo , Evolución Biológica , ADN Viral/genética
15.
Front Endocrinol (Lausanne) ; 15: 1341546, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38654930

RESUMEN

Objective: This study aimed to quantify the severity of metabolic syndrome(MetS) and investigate its association with cardiovascular disease(CVD) risk on Chinese adults. Methods: 13,500 participants from the Zhejiang Adult Chronic Disease Study were followed up between 2010 and 2021. A continuous MetS severity score derived from the five components of MetS was used to quantify MetS severity, and the association between MetS severity and the risk of incident CVD was assessed using Cox proportional hazard and restricted cubic spline regression. Results: Both the presence and severity of MetS were strongly associated with CVD risk. MetS was related to an increased risk of CVD (hazard ratio(HR):1.700, 95% confidence interval(CI): 1.380-2.094). Compared with the hazard ratio for CVD in the lowest quartile of the MetS severity score, that in the second, third, and highest quartiles were 1.812 (1.329-2.470), 1.746 (1.265-2.410), and 2.817 (2.015-3.938), respectively. A linear and positive dose-response relationship was observed between the MetS severity and CVD risk (P for non-linearity = 0.437). Similar results were found in various sensitivity analyses. Conclusion: The MetS severity score was significantly associated with CVD risk. Assessing MetS severity and further ensuring intervention measures according to the different severities of MetS may be more useful in preventing CVD.


Asunto(s)
Enfermedades Cardiovasculares , Síndrome Metabólico , Índice de Severidad de la Enfermedad , Humanos , Síndrome Metabólico/epidemiología , Síndrome Metabólico/complicaciones , Masculino , Enfermedades Cardiovasculares/epidemiología , Femenino , Persona de Mediana Edad , Estudios Longitudinales , Adulto , China/epidemiología , Factores de Riesgo , Anciano , Estudios de Cohortes , Estudios de Seguimiento , Incidencia , Pueblos del Este de Asia
16.
Langmuir ; 40(16): 8721-8729, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38598618

RESUMEN

Experimental studies have demonstrated that the gas phase contact angle (CA) of a surface nanobubble (SNB) is much smaller than that of a macroscopic gas bubble. This reduced CA plays a crucial role in prolonging the lifetime of SNBs by lowering the bubble pressure and preventing gas molecules from dissolving in the surrounding liquids. Despite extensive efforts to explain the anomalously small CA, a consensus about the underlying reasons is yet to be reached. In this study, we conducted experimental investigations to explore the influence of gas molecules adsorbed at the solid-liquid interface on the CA of SNBs created through the solvent exchange (SE) method and temperature difference (TD). Interestingly, no significant change is observed in the CA of SNBs on highly oriented pyrolytic graphite (HOPG) surfaces. Even for nanobubbles on micro/nano pancakes, the CA only exhibited a slight reduction compared to SNBs on bare HOPG surfaces. These findings suggest that gas adsorption at the immersed solid surface may not be the primary factor contributing to the small CA of the SNBs. Furthermore, the CA of SNBs formed on polystyrene (PS) and octadecyltrichlorosilane (OTS) substrates was also investigated, and a considerable increase in CA was observed. In addition, the effects of other factors including impurity, electric double layer (EDL) line tension, and pinning force upon the CA of SNBs were discussed, and a comprehensive model about multiple factors affecting the CA of SNBs was proposed, which is helpful for understanding the abnormally small CA and the stability of SNBs.

17.
Front Immunol ; 15: 1325860, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38487523

RESUMEN

Pancreatic cancer (PC) is one of the most malignant tumors in digestive system due to its highly invasive and metastatic properties. At present, conventional treatment strategies for PC show the limited clinical efficacy. Therefore, novel effective therapeutic strategies are urgently needed. Here, we report a case of complete remission of advanced PC induced by claudin18.2-targeted CAR-T cell therapy. The patient was a 72-year-old man who was diagnosed with pancreatic ductal adenocarcinoma 2 years ago, and he experienced tumor recurrence and multiple metastases after pancreaticoduodenectomy and multi-line chemotherapies, including liver, peritoneum, and cervical lymph node metastases. Then, the patient was referred to our department for further treatment of metastatic PC, and he was enrolled in a clinical trial of claudin18.2-targeted CAR-T cell therapy. After lymphodepleting chemotherapy, the patient received claudin18.2-targeted CAR-T cell infusion at a dose of 1.2 × 106 cells/kg on November 21, 2022. During CAR-T cell therapy, the patient experienced grade 2 cytokine release syndrome (CRS) and gastric mucosa injury, which were controlled by tocilizumab and conventional symptomatic and supportive treatment. The patient achieved a complete response (CR) 1 month after claudin18.2-targeted CAR-T cell therapy, and remained in clinical remission for 8 months. Unfortunately, the patient experienced claudin18.2-negative relapse in July, 2023. Despite antigen-negative relapse after claudin18.2-targeted CAR-T cell infusion, the patient achieved sustained remission for 8 months, which indicates that claudin18.2-targeted CAR-T cell therapy is an extremely effective therapeutic strategy for the treatment of advanced PC.


Asunto(s)
Neoplasias Pancreáticas , Receptores Quiméricos de Antígenos , Masculino , Humanos , Anciano , Recurrencia Local de Neoplasia , Neoplasias Pancreáticas/terapia , Respuesta Patológica Completa , Recurrencia , Tratamiento Basado en Trasplante de Células y Tejidos
18.
Nucleic Acids Res ; 52(7): 3837-3855, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38452213

RESUMEN

CCCTC-binding factor (CTCF) binding sites are hotspots of genome instability. Although many factors have been associated with CTCF binding site fragility, no study has integrated all fragility-related factors to understand the mechanism(s) of how they work together. Using an unbiased, genome-wide approach, we found that DNA double-strand breaks (DSBs) are enriched at strong, but not weak, CTCF binding sites in five human cell types. Energetically favorable alternative DNA secondary structures underlie strong CTCF binding sites. These structures coincided with the location of topoisomerase II (TOP2) cleavage complex, suggesting that DNA secondary structure acts as a recognition sequence for TOP2 binding and cleavage at CTCF binding sites. Furthermore, CTCF knockdown significantly increased DSBs at strong CTCF binding sites and at CTCF sites that are located at topologically associated domain (TAD) boundaries. TAD boundary-associated CTCF sites that lost CTCF upon knockdown displayed increased DSBs when compared to the gained sites, and those lost sites are overrepresented with G-quadruplexes, suggesting that the structures act as boundary insulators in the absence of CTCF, and contribute to increased DSBs. These results model how alternative DNA secondary structures facilitate recruitment of TOP2 to CTCF binding sites, providing mechanistic insight into DNA fragility at CTCF binding sites.


Asunto(s)
Factor de Unión a CCCTC , Roturas del ADN de Doble Cadena , ADN-Topoisomerasas de Tipo II , ADN , Conformación de Ácido Nucleico , ADN-Topoisomerasas de Tipo II/metabolismo , ADN-Topoisomerasas de Tipo II/genética , ADN-Topoisomerasas de Tipo II/química , Humanos , Factor de Unión a CCCTC/metabolismo , Factor de Unión a CCCTC/genética , Sitios de Unión , ADN/metabolismo , ADN/química , ADN/genética , Unión Proteica , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/genética , Proteínas de Unión a Poli-ADP-Ribosa/química , Línea Celular
19.
Sci Total Environ ; 926: 172065, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38556008

RESUMEN

As global anthropogenic nitrogen inputs continue to rise, nitrite-dependent anaerobic methane oxidation (N-DAMO) plays an increasingly significant role in CH4 consumption in lake sediments. However, there is a dearth of knowledge regarding the effects of anthropogenic activities on N-DAMO bacteria in lakes in the cold and arid regions. Sediment samples were collected from five sampling areas in Lake Ulansuhai at varying depth ranges (0-20, 20-40, and 40-60 cm). The ecological characterization and niche differentiation of N-DAMO bacteria were investigated using bioinformatics and molecular biology techniques. Quantitative PCR confirmed the presence of N-DAMO bacteria in Lake Ulansuhai sediments, with 16S rRNA gene abundances ranging from 1.72 × 104 to 5.75 × 105 copies·g-1 dry sediment. The highest abundance was observed at the farmland drainage outlet with high available phosphorus (AP). Anthropogenic disturbances led to a significant increase in the abundance of N-DAMO bacteria, though their diversity remained unaffected. The heterogeneous community of N-DAMO bacteria was affected by interactions among various environmental characteristics, with AP and oxidation-reduction potential identified as the key drivers in this study. The Mantel test indicated that the N-DAMO bacterial abundance was more readily influenced by the presence of the denitrification genes (nirS and nirK). Network analysis revealed that the community structure of N-DAMO bacteria generated numerous links (especially positive links) with microbial taxa involved in carbon and nitrogen cycles, such as methanogens and nitrifying bacteria. In summary, N-DAMO bacteria exhibited sensitivity to both environmental and microbial factors under various human disturbances. This study provides valuable insights into the distribution patterns of N-DAMO bacteria and their roles in nitrogen and carbon cycling within lake ecosystems.


Asunto(s)
Microbiota , Nitritos , Humanos , Lagos/microbiología , Anaerobiosis , Metano , ARN Ribosómico 16S/genética , Bacterias/genética , Methanobacteriaceae , Bacterias Anaerobias/genética , Oxidación-Reducción , Nitrógeno , Carbono , Desnitrificación
20.
Chem Rev ; 124(7): 4479-4539, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38552165

RESUMEN

Crystal phase, a critical structural characteristic beyond the morphology, size, dimension, facet, etc., determines the physicochemical properties of nanomaterials. As a group of layered nanomaterials with polymorphs, transition metal dichalcogenides (TMDs) have attracted intensive research attention due to their phase-dependent properties. Therefore, great efforts have been devoted to the phase engineering of TMDs to synthesize TMDs with controlled phases, especially unconventional/metastable phases, for various applications in electronics, optoelectronics, catalysis, biomedicine, energy storage and conversion, and ferroelectrics. Considering the significant progress in the synthesis and applications of TMDs, we believe that a comprehensive review on the phase engineering of TMDs is critical to promote their fundamental studies and practical applications. This Review aims to provide a comprehensive introduction and discussion on the crystal structures, synthetic strategies, and phase-dependent properties and applications of TMDs. Finally, our perspectives on the challenges and opportunities in phase engineering of TMDs will also be discussed.

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