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1.
Neural Regen Res ; 20(1): 224-233, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38767487

RESUMO

JOURNAL/nrgr/04.03/01300535-202501000-00030/figure1/v/2024-05-14T021156Z/r/image-tiff Axonal remodeling is a critical aspect of ischemic brain repair processes and contributes to spontaneous functional recovery. Our previous in vitro study demonstrated that exosomes/small extracellular vesicles (sEVs) isolated from cerebral endothelial cells (CEC-sEVs) of ischemic brain promote axonal growth of embryonic cortical neurons and that microRNA 27a (miR-27a) is an elevated miRNA in ischemic CEC-sEVs. In the present study, we investigated whether normal CEC-sEVs engineered to enrich their levels of miR-27a (27a-sEVs) further enhance axonal growth and improve neurological outcomes after ischemic stroke when compared with treatment with non-engineered CEC-sEVs. 27a-sEVs were isolated from the conditioned medium of healthy mouse CECs transfected with a lentiviral miR-27a expression vector. Small EVs isolated from CECs transfected with a scramble vector (Scra-sEVs) were used as a control. Adult male mice were subjected to permanent middle cerebral artery occlusion and then were randomly treated with 27a-sEVs or Scra-sEVs. An array of behavior assays was used to measure neurological function. Compared with treatment of ischemic stroke with Scra-sEVs, treatment with 27a-sEVs significantly augmented axons and spines in the peri-infarct zone and in the corticospinal tract of the spinal grey matter of the denervated side, and significantly improved neurological outcomes. In vitro studies demonstrated that CEC-sEVs carrying reduced miR-27a abolished 27a-sEV-augmented axonal growth. Ultrastructural analysis revealed that 27a-sEVs systemically administered preferentially localized to the pre-synaptic active zone, while quantitative reverse transcription-polymerase chain reaction and Western Blot analysis showed elevated miR-27a, and reduced axonal inhibitory proteins Semaphorin 6A and Ras Homolog Family Member A in the peri-infarct zone. Blockage of the Clathrin-dependent endocytosis pathway substantially reduced neuronal internalization of 27a-sEVs. Our data provide evidence that 27a-sEVs have a therapeutic effect on stroke recovery by promoting axonal remodeling and improving neurological outcomes. Our findings also suggest that suppression of axonal inhibitory proteins such as Semaphorin 6A may contribute to the beneficial effect of 27a-sEVs on axonal remodeling.

2.
Chin Med ; 19(1): 91, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956695

RESUMO

BACKGROUND: Angelicin, which is found in Psoralea, can help prevent osteoporosis by stopping osteoclast formation, although the precise mechanism remains unclear. METHODS: We evaluated the effect of angelicin on the oxidative stress level of osteoclasts using ovariectomized osteoporosis model rats and RAW264.7 cells. Changes in the bone mass of the femur were investigated using H&E staining and micro-CT. ROS content was investigated by DHE fluorescence labelling. Osteoclast-related genes and proteins were examined for expression using Western blotting, immunohistochemistry, tartrate-resistant acid phosphatase staining, and real-time quantitative PCR. The influence of angelicin on osteoclast development was also evaluated using the MTT assay, double luciferin assay, chromatin immunoprecipitation, immunoprecipitation and KAT6A siRNA transfection. RESULTS: Rats treated with angelicin had considerably higher bone mineral density and fewer osteoclasts. Angelicin prevented RAW264.7 cells from differentiating into osteoclasts in vitro when stimulated by RANKL. Experiments revealed reduced ROS levels and significantly upregulated intracellular KAT6A, HO-1, and Nrf2 following angelicin treatment. The expression of genes unique to osteoclasts, such as MMP9 and NFATc1, was also downregulated. Finally, KAT6A siRNA transfection increased intracellular ROS levels while decreasing KAT6A, Nrf2, and HO-1 protein expression in osteoclasts. However, in the absence of KAT6A siRNA transfection, angelicin greatly counteracted this effect in osteoclasts. CONCLUSIONS: Angelicin increased the expression of KAT6A. This enhanced KAT6A expression helps to activate the Nrf2/HO-1 antioxidant stress system and decrease ROS levels in osteoclasts, thus inhibiting oxidative stress levels and osteoclast formation.

3.
Cancer Invest ; 42(6): 527-537, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38965994

RESUMO

Despite the emergence of various treatment strategies for rectal cancer based on neoadjuvant chemoradiotherapy, there is currently a lack of reliable biomarkers to determine which patients will respond well to neoadjuvant chemoradiotherapy. Through collecting hematological and biochemical parameters data of patients prior to receiving neoadjuvant chemoradiotherapy, we evaluated the predictive value of systemic inflammatory indices for pathological response and prognosis in rectal cancer patients. We found that baseline GRIm-Score was an independent predictor for MPR in rectal cancer patients. However, no association was observed between several commonly systemic inflammation indices and long-term outcome.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Humanos , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Neoplasias Retais/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Idoso , Quimioembolização Terapêutica/métodos , Prognóstico , Resultado do Tratamento , Adulto , Quimiorradioterapia/métodos
4.
World J Radiol ; 16(6): 211-220, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38983836

RESUMO

BACKGROUND: Solid pseudopapillary neoplasms of the pancreas (SPN) share similar imaging findings with pancreatic ductal adenocarcinoma with cystic changes (PDAC with cystic changes), which may result in unnecessary surgery. AIM: To investigate the value of computed tomography (CT) in differentiation of SPN from PDAC with cystic changes. METHODS: This study retrospectively analyzed the clinical and imaging findings of 32 patients diagnosed with SPN and 14 patients diagnosed with PDAC exhibiting cystic changes, confirmed through pathological diagnosis. Quantitative and qualitative analysis was performed, including assessment of age, sex, tumor size, shape, margin, density, enhancement pattern, CT values of tumors, CT contrast enhancement ratios, "floating cloud sign," calcification, main pancreatic duct dilatation, pancreatic atrophy, and peripancreatic invasion or distal metastasis. Multivariate logistic regression analysis was used to identify relevant features to differentiate between SPN and PDAC with cystic changes, and receiver operating characteristic curves were obtained to evaluate the diagnostic performance of each variable and their combination. RESULTS: When compared to PDAC with cystic changes, SPN had a lower age (32 years vs 64 years, P < 0.05) and a slightly larger size (5.41 cm vs 3.90 cm, P < 0.05). SPN had a higher frequency of "floating cloud sign" and peripancreatic invasion or distal metastasis than PDAC with cystic changes (both P < 0.05). No significant difference was found with respect to sex, tumor location, shape, margin, density, main pancreatic duct dilatation, calcification, pancreatic atrophy, enhancement pattern, CT values of tumors, or CT contrast enhancement ratios between the two groups (all P > 0.05). The area under the receiver operating characteristic curve of the combination was 0.833 (95% confidence interval: 0.708-0.957) with 78.6% sensitivity, 81.3% specificity, and 80.4% accuracy in differentiation of SPN from PDAC with cystic changes. CONCLUSION: A larger tumor size, "floating cloud sign," and peripancreatic invasion or distal metastasis are useful CT imaging features that are more common in SPN and may help discriminate SPN from PDAC with cystic changes.

5.
World J Oncol ; 15(4): 695-710, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38993245

RESUMO

Background: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors originating from the digestive system. Tertiary lymphoid structures (TLS), non-lymphoid tissues outside of the lymphoid organs, are closely connected to chronic inflammation and tumorigenesis. However, the detailed relationship between TLS and HCC prognosis remained unclear. In this study, we aimed to construct a TLS-related gene signature for predicting the prognosis of HCC patients. Methods: The Cancer Genome Atlas (TCGA) clinical data from 369 HCC tissues and 50 normal liver tissues were utilized to examine the differential expression of TLS-related genes. Based on least absolute shrinkage and selection operator (LASSO) Cox regression analysis, the prognostic model was constructed using the TCGA cohort and validated in the GSE14520 cohort and International Cancer Genome Consortium (ICGC) cohort. The Kaplan-Meier (KM) and receiver operating characteristic (ROC) curves were employed to validate the predictive ability of the prognostic model. Furthermore, Cox regression analysis was applied to identify whether the TLS score could be employed as an independent prognosis factor. A nomogram was developed to predict the survival probability of HCC patients. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were performed for TLS-related genes. Genetic mutation analysis, the CIBERSORT algorithm, and single-sample gene set enrichment analysis (ssGSEA) were used to assess the tumor mutation landscape and immune infiltration. Finally, the role of the TLS score in HCC therapy was investigated. Results: Six genes were included in the construction of our prognostic model (CETP, DNASE1L3, PLAC8, SKAP1, C7, and VNN2), and we validated its accuracy. Survival analysis showed that patients in the high-TLS score group had a significantly better overall survival than those in the low-TLS score group. Univariate, multivariate Cox regression analysis and the establishment of a nomogram indicated that the TLS score could independently function as a potential prognostic marker. A significant association between TLS score and immunity was revealed by an analysis of gene alterations and immune cell infiltration. In addition, two subtypes of the TLS score could accurately predict the effectiveness of sorafenib, transcatheter arterial chemoembolization (TACE), and immunotherapy in HCC patients. Conclusion: In this research, we conducted and validated a prognostic model associated with TLS that may be helpful for predicting clinical outcomes and treatment responsiveness for HCC patients.

6.
Small Methods ; : e2400373, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984758

RESUMO

For in vitro neutrophil functional assays, neutrophils are typically isolated from whole blood, having the target cells exposed to an artificial microenvironment with altered kinetics. Isolated neutrophils exhibit limited lifespans of only a few hours ex vivo, significantly shorter than the 3-5 day lifespan of neutrophils in vivo. In addition, due to neutrophils' inherently high sensitivity, neutrophils removed from whole blood exhibit stochastic non-specific activation that contributes to assay variability. Here, a method - named "µ-Blood" - is presented that enables functional neutrophil assays using a microliter of unprocessed whole blood. µ-Blood allows multiple phenotypic readouts of neutrophil function (including cell/nucleus morphology, motility, recruitment, and pathogen control). In µ-Blood, neutrophils show sustained migration and limited non-specific activation kinetics (<0.1% non-specific activation) over 3-6 days. In contrast, neutrophils isolated using traditional methods show increased and divergent activation kinetics (10-70% non-specific activation) in only 3 h. Finally, µ-Blood allows the capture and quantitative comparison of distinct neutrophil functional heterogeneity between healthy donors and cancer patients in response to microbial stimuli with the preserved physiological lifespan over 6 days.

7.
Biointerphases ; 19(4)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38984804

RESUMO

Topical ophthalmic solutions (eye drops) are becoming increasingly popular in treating and preventing ocular diseases for their safety, noninvasiveness, and ease of handling. However, the static and dynamic barriers of eyes cause the extremely low bioavailability (<5%) of eye drops, making ocular therapy challenging. Thus, drug-eluting corneal contact lenses (DECLs) have been intensively investigated as a drug delivery device for their attractive properties, such as sustained drug release and improved bioavailability. In order to promote the clinical application of DECLs, multiple aspects, i.e., drug release and penetration, safety, and biocompatibility, of these drug delivery systems were thoroughly examined. In this review, we systematically discussed advances in DECLs, including types of preparation materials, drug-loading strategies, drug release mechanisms, strategies for penetrating ocular barriers, in vitro and in vivo drug delivery and penetration detection, safety, and biocompatibility validation methods, as well as challenges and future perspectives.


Assuntos
Lentes de Contato , Sistemas de Liberação de Medicamentos , Soluções Oftálmicas , Humanos , Animais , Córnea/metabolismo , Disponibilidade Biológica
8.
Adv Sci (Weinh) ; : e2401171, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973363

RESUMO

Ripretinib, a broad-spectrum inhibitor of the KIT and PDGFRA receptor tyrosine kinases, is designated as a fourth-line treatment for gastrointestinal stromal tumor (GIST). It is tailored for patients resistant to imatinib, sunitinib, and regorafenib. As its increasing use, instances of resistance to ripretinib are becoming more frequent. Unfortunately, there are currently no scientifically mature treatment options available for patients resistant to ripretinib. Posttranslational modifications (PTMs) such as ubiquitination, in conjunction with its interplay with other modifications, play a collective role in regulating tumor initiation and progression. However, the specific association between ubiquitination and ripretinib resistance is not reported. Through proteome-ubiquitinome sequencing, increased levels of the USP5 protein and decreased ubiquitination in ripretinib-resistant GISTs are detected. Subsequent examination of the mass spectrometry findings validated the interaction through which TRIM21 governs USP5 expression via ubiquitination, and USP5 regulates MDH2 expression through deubiquitination, consequently fostering ripretinib resistance in GIST. Moreover, ZDHHC18 can palmitoylate MDH2, preventing its ubiquitination and further increasing its protein stability. The research underscores the correlation between posttranslational modifications, specifically ubiquitination, and drug resistance, emphasizing the potential of targeting the USP5-MDH2 axis to counteract ripretinib resistance in GIST.

9.
J Microbiol Biotechnol ; 34(7): 1455-1465, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38973400

RESUMO

Soil extracellular enzyme plays a vital role in changing soil nitrogen (N) mineralization of rice field. However, the effects of soil extracellular enzyme activities (EEA) and microbial community composition response to N mineralization of rice field under short-term tillage treatment needed to be further explored. In this study, we investigated the impact of short-term (8-year) tillage practices on rhizosphere soil N transformation rate, soil enzyme activities, soil microorganism community structure and their N mineralization function genes in double-cropping rice field in southern China. The experiment consisted of four tillage treatments: rotary tillage with crop straw input (RT), conventional tillage with crop straw input (CT), no-tillage with crop straw retention (NT), and rotary tillage with all crop straws removed as a control (RTO). The results indicated that rhizosphere soil N transformation rate in paddy field in NT and RTO treatments were significantly lower than that in RT and CT treatments. Compared with NT and RTO treatments, soil protease, urease, ß-glucosaminidase and arginase activities with CT treatment were significantly improved, as were abundances of soil sub, npr and chiA with CT and RT treatments. Moreover, diversity of overall soil bacterial communities in NT and RTO treatments were significantly lower than that in RT and CT treatments. Soil chitinolytic and bacterial ureolytic communities were also obviously changed combined with tillage and crop straw input practices.

10.
Hepatology ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954820

RESUMO

Alpha-1 antitrypsin deficiency (A1ATD) is a life-threatening condition caused by inheritance of the SERPINA1 'Z' genetic variant (PiZ) driving AAT protein misfolding in hepatocytes. There remain no approved medicines for this disease. Here, we report the results of a small molecule screen performed in patient derived iPSC-hepatocytes that identified Leucine-rich repeat kinase-2 (LRRK2) as a potentially new therapeutic target. Of the commercially available LRRK2 inhibitors tested, we identified CZC-25146, a candidate with favorable pharmacokinetic properties, as being capable of reducing polymer load, increasing normal AAT secretion, and reducing inflammatory cytokines in both cells and PiZ mice. Mechanistically, this effect was achieved through induction of autophagy. Our findings support the use of CZC-25146 and LRRK2 inhibitors in hepatic proteinopathy research and their further investigation as novel therapeutic candidates for A1ATD.

11.
J Environ Manage ; 366: 121713, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38986368

RESUMO

Spirulina platensis contains abundant nitrogen-containing organics, which might react with derivatives of cellulose/lignin during hydrothermal carbonization (HTC), probably affecting yield, property of hydrochar, and pore development in activation of hydrochar. This was investigated herein by conducting co-HTC of spirulina platensis with cellulose, lignin, and sawdust at 260 °C and subsequent activation of the resulting hydrochars with K2C2O4 at 800 °C. The results showed that cross-condensation of spirulina platensis-derived proteins with cellulose/lignin-derived ketones and phenolics did take place in the co-HTC, forming more π-conjugated heavier organics, retaining more nitrogen species in hydrochar, reducing yields of hydrochar, making the hydrochar more aromatic and increasing the thermal stability and resistivity towards activation. This enhanced the yield of activated carbon (AC) by 7 %-20 % and significantly increased specific surface area of the AC from activation of hydrochar of spirulina platensis + lignin to 2074.5 m2/g (859.3 m2/g from spirulina platensis only and 1170.1 m2/g from lignin only). Furthermore, more mesopores from activation of hydrochar of spirulina platensis + cellulose (47 %) and more micropores from activation of hydrochar of spirulina + sawdust (93 %) was generated. The AC from spirulina platensis + lignin with the developed pore structures generated sufficient sites for adsorption of tetracycline from aqueous phase and minimized steric hindrance for mass transfer with the abundant mesopores (43 %).

12.
Rev Esp Enferm Dig ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967262

RESUMO

EUS-GUIDED biliary drainage (EUS-BD) has recently gained widespread acceptance as a minimally invasive alternative method for biliary drainage. However, the risks of encountering recurrent biliary obstruction (RBO) after EUS-BD have increased due to the growing clinical experience of EUS-BD and prolonged prognosis of the underlying disease. Previous studies have shown that the incidence of RBO following EUS-BD ranges from 11% to 25%. Nevertheless, literature on the efficacy of reintervention of RBO after EUS-GUIDED hepaticogastrostomy (EUS-HGS) and case reports describing the procedural details of endoscopic reintervention following EUS-HGS are lacking.

13.
Rev Esp Enferm Dig ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989864

RESUMO

Pancreatic cutaneous fistula is a complex condition, making it challenging to achieve favorable outcomes with conservative medical treatment. Surgical interventions often entail surgical risks and postoperative complications. Here, we present a case involving endoscopically guided stent placement between the stomach and the fistula. By internalizing the fistula, patients can potentially remove the external drainage tube, offering a novel endoscopic treatment approach for such cases.

14.
World J Gastrointest Oncol ; 16(6): 2404-2418, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38994138

RESUMO

BACKGROUND: Research on gastrointestinal mucosal adenocarcinoma (GMA) is limited and controversial, and there is no reference tool for predicting postoperative survival. AIM: To investigate the prognosis of GMA and develop predictive model. METHODS: From the Surveillance, Epidemiology, and End Results database, we collected clinical information on patients with GMA. After random sampling, the patients were divided into the discovery (70% of the total, for model training), validation (20%, for model evaluation), and completely blind test cohorts (10%, for further model evaluation). The main assessment metric was the area under the receiver operating characteristic curve (AUC). All collected clinical features were used for Cox proportional hazard regression analysis to determine factors influencing GMA's prognosis. RESULTS: This model had an AUC of 0.7433 [95% confidence intervals (95%CI): 0.7424-0.7442] in the discovery cohort, 0.7244 (GMA: 0.7234-0.7254) in the validation cohort, and 0.7388 (95%CI: 0.7378-0.7398) in the test cohort. We packaged it into Windows software for doctors' use and uploaded it. Mucinous gastric adenocarcinoma had the worst prognosis, and these were protective factors of GMA: Regional nodes examined [hazard ratio (HR): 0.98, 95%CI: 0.97-0.98, P < 0.001)] and chemotherapy (HR: 0.62, 95%CI: 0.58-0.66, P < 0.001). CONCLUSION: The deep learning-based tool developed can accurately predict the overall survival of patients with GMA postoperatively. Combining surgery, chemotherapy, and adequate lymph node dissection during surgery can improve patient outcomes.

15.
Poult Sci ; 103(9): 104019, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38991384

RESUMO

Meat qualities of free-range chicken (Xuan-Zhou) (XZ-FRC) are closely associated with slaughter age and directly influence the economic benefits of supplier and consumer's preference. Understanding of the relationship between meat qualities and ages will be of prime important to explore a better slaughter age of XZ-FRC. In this study, the quality traits of breast and thigh muscles from XZ-FRCs at 9 to 14 wk were analyzed to establish a relatively reliable method for selecting a better slaughter age. The results showed that the effects of slaughter ages on color (CIE L*, a* and b* values), shear force, centrifugal loss, and flavor of XZ-FRCs were significant (P < 0.05). There were greater differences in meat qualities, whatever breast or thigh muscles, between same or different ages. Eleven feature indexes used for colligation evaluation of slaughter age were selected by combining the quality characteristics and data analysis. The score of colligation evaluation for XZ-FRCs at 12 wk was higher than that at 9 and 14 wk, suggesting that the 12 wk was an optimal slaughter age. This work would provide a reference method that helps the producers of livestock and poultry to select a better slaughter age.

16.
J Dermatolog Treat ; 35(1): 2337264, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38991550

RESUMO

BACKGROUND: While extensive research has provided a wealth of information on psoriasis in general, there remains a critical gap in understanding the unique characteristics of psoriasis in special body areas, such as the scalp, nails, palms, and genitals. OBJECTIVE: To investigate the characterization and treatment of psoriasis patients in special body areas. METHODS: The study was a retrospective analysis of patients with psoriasis enrolled in the Psoriasis Standardized Diagnosis and Treatment Center Project between January 2020 and September 2021. RESULTS: The study encompassed 346 patients, 81% of them had psoriasis in at least two special body areas, with the nails as the most common area. Patients with genital psoriasis reported higher Dermatology Life Quality Index (DLQI) scores. A higher propensity for scalp and palmoplantar psoriasis was noted in patients with genital psoriasis. The proportion of patients treated with biologics rose, as the number of specific areas involved increased. CONCLUSIONS: Patients with genital psoriasis are more likely to have scalp and palmoplantar psoriasis. This study highlights the significant escalation in the proportion of biologics when the involvement of special body areas was ≥2.


Assuntos
Psoríase , Humanos , Psoríase/diagnóstico , Psoríase/tratamento farmacológico , Estudos Retrospectivos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , China , Qualidade de Vida , Dermatoses do Couro Cabeludo/diagnóstico , Produtos Biológicos/uso terapêutico , Índice de Gravidade de Doença , Fármacos Dermatológicos/uso terapêutico , Idoso , População do Leste Asiático
17.
Sci Total Environ ; : 174693, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992364

RESUMO

Rewilding abandoned farmlands provides a nature-based climate solution via carbon (C) offsetting; however, the C-cycle-climate feedback in such restored ecosystems is poorly understood. Therefore, we conducted a 2-year field experiment in Loess Plateau, China, to determine the impacts of warming (~1.4 °C) and altered precipitation (±25 %, ±50 %, and ambient), alone or in concert on soil C pools and associated C fluxes. Experimental warming significantly enhanced soil respiration without affecting the ecosystem net C uptake and soil C storage; these variables tended to increase along the manipulated precipitation gradient. Their interactions increased ecosystem net C uptake (synergism) but decreased soil respiration and soil C accumulation (antagonism) compared with a single warming or altered precipitation. Additionally, most variables related to the C cycle tended to be more responsive to increased precipitation, but the ecosystem net C uptake responded intensely to warming and decreased precipitation. Overall, ecosystem net C uptake and soil C storage increased by 94.4 % and 8.2 %, respectively, under the warmer-wetter scenario; however, phosphorus deficiency restricted soil C accumulation under these climatic conditions. By contrast, ecosystem net C uptake and soil C storage decreased by 56.6 % and 13.6 %, respectively, when exposed to the warmer-drier climate, intensifying its tendency toward a C source. Therefore, the C sink function of semiarid abandoned farmland was unsustainable. Our findings emphasize the need for management of post-abandonment regeneration to sustain ecosystem C sequestration in the context of climate change, aiding policymakers in the development of C-neutral routes in abandoned regions.

18.
Sci Total Environ ; : 174656, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992367

RESUMO

Microorganisms are vital to the emission of greenhouse gases and transforming pollutants in paddy soils. However, the impact of microbial diversity loss on anaerobic methane (CH4) oxidation and arsenic (As) reduction under flooded conditions remains unclear. In this study, we inoculated microbial suspensions into natural As-contaminated paddy soils using a dilution approach (untreated, 10-2, 10-4, 10-6, 10-8 dilutions) to manipulate microbial diversity levels. The results revealed that the 10-4 and 10-6 dilutions resulted in the highest CH4 emissions (97.0 µmol and 102.3 µmol) compared to untreated groups (27.6 µmol). However, anaerobic CH4 oxidation was not observed in 10-4 dilution groups and higher dilutions, suggesting the loss of diversity inhibited the natural reduction of CH4. Moreover, the porewater As concentration in the dilution groups was 1.8-8.2 times greater than in the untreated groups. The loss of microbial diversity promoted the reductive dissolution of iron (Fe) minerals bearing As, leading to increased concentrations of Fe(II) and dissolved organic carbon (DOC), which further enhanced As release (Fe(II), R = 0.9, p < 0.001) (DOC, R = 0.8, p < 0.001) from soil to porewater. However, CH4-dependent As(V) reduction was almost entirely inhibited under diversity loss. The decline in microbial diversity increased the relative abundances of methanogens (e.g., Methanobacterium and Methanomassiliicoccus), Fe(III)/As(V)-reducing bacteria (e.g., Bacillus, Clostridium_sensu_stricto_10, and Geobacter), and the related functional genes (i.e., mcrA and Geo). These findings suggest that microbial diversity is critical for specialized soil processes, highlighting the detrimental effects of biodiversity loss on CH4 emissions and As release in As-contaminated paddies.

19.
Front Immunol ; 15: 1426474, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38947325

RESUMO

Background: Monocytes play a critical role in tumor initiation and progression, with their impact on prostate adenocarcinoma (PRAD) not yet fully understood. This study aimed to identify key monocyte-related genes and elucidate their mechanisms in PRAD. Method: Utilizing the TCGA-PRAD dataset, immune cell infiltration levels were assessed using CIBERSORT, and their correlation with patient prognosis was analyzed. The WGCNA method pinpointed 14 crucial monocyte-related genes. A diagnostic model focused on monocytes was developed using a combination of machine learning algorithms, while a prognostic model was created using the LASSO algorithm, both of which were validated. Random forest and gradient boosting machine singled out CCNA2 as the most significant gene related to prognosis in monocytes, with its function further investigated through gene enrichment analysis. Mendelian randomization analysis of the association of HLA-DR high-expressing monocytes with PRAD. Molecular docking was employed to assess the binding affinity of CCNA2 with targeted drugs for PRAD, and experimental validation confirmed the expression and prognostic value of CCNA2 in PRAD. Result: Based on the identification of 14 monocyte-related genes by WGCNA, we developed a diagnostic model for PRAD using a combination of multiple machine learning algorithms. Additionally, we constructed a prognostic model using the LASSO algorithm, both of which demonstrated excellent predictive capabilities. Analysis with random forest and gradient boosting machine algorithms further supported the potential prognostic value of CCNA2 in PRAD. Gene enrichment analysis revealed the association of CCNA2 with the regulation of cell cycle and cellular senescence in PRAD. Mendelian randomization analysis confirmed that monocytes expressing high levels of HLA-DR may promote PRAD. Molecular docking results suggested a strong affinity of CCNA2 for drugs targeting PRAD. Furthermore, immunohistochemistry experiments validated the upregulation of CCNA2 expression in PRAD and its correlation with patient prognosis. Conclusion: Our findings offer new insights into monocyte heterogeneity and its role in PRAD. Furthermore, CCNA2 holds potential as a novel targeted drug for PRAD.


Assuntos
Imunoterapia , Monócitos , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/terapia , Neoplasias da Próstata/diagnóstico , Monócitos/imunologia , Monócitos/metabolismo , Prognóstico , Imunoterapia/métodos , Biomarcadores Tumorais/genética , Aprendizado de Máquina , Simulação de Acoplamento Molecular , Regulação Neoplásica da Expressão Gênica , Perfilação da Expressão Gênica , Biologia Computacional/métodos , Multiômica
20.
J Am Chem Soc ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950118

RESUMO

Enantioselective construction of all-carbon quaternary stereocenters has attracted much attention over the past few decades. A variety of catalytic asymmetric methods have been disclosed based on the use of presynthesized complex reagents that impart congested steric hindrance to the reaction center, which generally produce the chiral molecules through forming one C-C bond. The use of readily available reagents that could build two C-C bonds on the same carbonic center with the concomitant assembly of quaternary stereocenters remains challenging. Herein, we disclose a catalytic asymmetric alkyne multifunctionalization reaction using a gold complex and a chiral spiro phosphoric acid (SPA) for synergistic catalysis. In this method, the readily accessible internal alkynes served as the key gold carbene precursors, followed by carbene gem-dialkylation through Mannich-type addition of enolate species or stepwise formal cycloaddition with methylenimines that are derived from 1,3,5-triazinanes in the presence of SPA. The reaction provides practical access to poly-functionalized chiral linear and cyclic ketones that bear two adjacent quaternary stereocenters in generally good yields and excellent enantioselectivities, leading to an essential complement to the asymmetric construction of quaternary stereocenters using readily available materials with high bond formation efficiency.

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