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1.
Water Res ; 262: 122113, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39032335

RESUMEN

Mangrove aquatic ecosystems receive substantial nitrogen (N) inputs from both land and sea, playing critical roles in modulating coastal N fluxes. The microbially-mediated competition between denitrification and dissimilatory nitrate reduction to ammonium (DNRA) in mangrove sediments significantly impacts the N fate and transformation processes. Despite their recognized role in N loss or retention in surface sediments, how these two processes vary with sediment depths and their influential factors remain elusive. Here, we employed a comprehensive approach combining 15N isotope tracer, quantitative PCR (qPCR) and metagenomics to verify the vertical dynamics of denitrification and DNRA across five 100-cm mangrove sediment cores. Our results revealed a clear vertical partitioning, with denitrification dominated in 0-30 cm sediments, while DNRA played a greater role with increasing depths. Quantification of denitrification and DNRA functional genes further explained this phenomenon. Taxonomic analysis identified Pseudomonadota as the primary denitrification group, while Planctomycetota and Pseudomonadota exhibited high proportion in DNRA group. Furthermore, genome-resolved metagenomics revealed multiple salt-tolerance strategies and aromatic compound utilization potential in denitrification assemblages. This allowed denitrification to dominate in oxygen-fluctuating and higher-salinity surface sediments. However, the elevated C/N in anaerobic deep sediments favored DNRA, tending to generate biologically available NH4+. Together, our results uncover the depth-related variations in the microbially-mediated competition between denitrification and DNRA, regulating N dynamics in mangrove ecosystems.


Asunto(s)
Compuestos de Amonio , Desnitrificación , Sedimentos Geológicos , Microbiota , Nitratos , Nitratos/metabolismo , Sedimentos Geológicos/microbiología , Compuestos de Amonio/metabolismo , Humedales
2.
Ecol Evol ; 14(7): e70040, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39021733

RESUMEN

Mangrove sediments host a diverse array of microbial populations and are characterized by high heterogeneity along their vertical depths. However, the genetic diversity within these populations is largely unknown, hindering our understanding of their adaptive evolution across the sediment depths. To elucidate their genetic diversity, we utilized metagenome sequencing to identify 16 high-frequency microbial populations comprised of two archaea and 14 bacteria from mangrove sediment cores (0-100 cm, with 10 depths) in Qi'ao Island, China. Our analysis of the genome-wide genetic variation revealed extensive nucleotide diversity in the microbial populations. The genes involved in the transport and the energy metabolism displayed a high nucleotide diversity (HND; 0.0045-0.0195; an indicator of shared minor alleles with the microbial populations). By tracking the processes of homologous recombination, we found that each microbial population was subjected to different purification selection levels at different depths (44.12% genes). This selection resulted in significant differences in synonymous/non-synonymous mutation ratio between 0-20 and 20-100 cm layers, indicating the adaptive evolutionary process of microbial populations. Furthermore, our assessment of differentiation in the allele frequencies between these two layers showed that the functional genes involved in the metabolic processes of amino acids or cofactors were highly differential in more than half of them. Together, we showed that the nucleotide diversity of microbial populations was shaped by homologous recombination and gene-specific selection, finally resulting in the stratified differentiation occurring between 0-20 and 20-100 cm. These results enhance our cognition of the microbial adaptation mechanisms to vertical environmental changes during the sedimentation process of coastal blue carbon ecosystems.

3.
Int Immunopharmacol ; 137: 112417, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-38897122

RESUMEN

Drug local delivery system that directly supply anti-cancer drugs to the tumor microenvironment (TME) results in excellent tumor control and minimizes side effects associated with the anti-cancer drugs. Immune checkpoint inhibitors (ICIs) have been the mainstay of cancer immunotherapy. However, the systemic administration of ICIs is accompanied by considerable immunotherapy-related toxicity. To explore whether an anti-PD-L1 antibody administered locally via a sustained-release gel-forming carrier retains its effective anticancer function while causing fewer colitis-like side effects, CT, a previously reported depot system, was used to locally deliver an anti-PD-L1 antibody together with curcumin to the TME in bladder cancer-bearing ulcerative colitis model mice. We showed that CT-mediated intratumoral coinjection of an anti-PD-L1 antibody and curcumin enabled sustained release of both the loaded anti-PD-L1 antibody and curcumin, which contributed to substantial anticancer effects with negligible side effects on the colons of the UC model mice. However, although the anti-PD-L1 antibody administered systemically synergized with the CT-mediated intratumoral delivery of curcumin in inhibiting tumour growth, colitis was significantly worsened by intraperitoneal administration of anti-PD-L1 antibody. These findings suggested that CT is a promising agent for the local delivery of anticancer drugs, as it can allow effective anticancer functions to be retained while sharply reducing the adverse side effects associated with the systemic administration of these drugs.


Asunto(s)
Antígeno B7-H1 , Curcumina , Inhibidores de Puntos de Control Inmunológico , Inmunoterapia , Neoplasias de la Vejiga Urinaria , Animales , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/inmunología , Neoplasias de la Vejiga Urinaria/terapia , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/inmunología , Curcumina/uso terapéutico , Curcumina/administración & dosificación , Ratones , Inmunoterapia/métodos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Humanos , Línea Celular Tumoral , Femenino , Colitis/inducido químicamente , Colitis/inmunología , Colitis/tratamiento farmacológico , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Sistemas de Liberación de Medicamentos , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Antineoplásicos Inmunológicos/administración & dosificación , Antineoplásicos Inmunológicos/uso terapéutico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/inmunología
4.
Front Microbiol ; 15: 1355859, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716172

RESUMEN

Increasing nitrogen (N) input to coastal ecosystems poses a serious environmental threat. It is important to understand the responses and feedback of N removal microbial communities, particularly nitrifiers including the newly recognized complete ammonia-oxidizers (comammox), to improve aquaculture sustainability. In this study, we conducted a holistic evaluation of the functional communities responsible for nitrification by quantifying and sequencing the key functional genes of comammox Nitrospira-amoA, AOA-amoA, AOB-amoA and Nitrospira-nxrB in fish ponds with different fish feeding levels and evaluated the contribution of nitrifiers in the nitrification process through experiments of mixing pure cultures. We found that higher fish feeding dramatically increased N-related concentration, affecting the nitrifying communities. Compared to AOA and AOB, comammox Nitrospira and NOB were more sensitive to environmental changes. Unexpectedly, we detected an equivalent abundance of comammox Nitrospira and AOB and observed an increase in the proportion of clade A in comammox Nitrospira with the increase in fish feeding. Furthermore, a simplified network and shift of keystone species from NOB to comammox Nitrospira were observed in higher fish-feeding ponds. Random forest analysis suggested that the comammox Nitrospira community played a critical role in the nitrification of eutrophic aquaculture ponds (40-70 µM). Through the additional experiment of mixing nitrifying pure cultures, we found that comammox Nitrospira is the primary contributor to the nitrification process at 200 µM ammonium. These results advance our understanding of nitrifying communities and highlight the importance of comammox Nitrospira in driving nitrification in eutrophic aquaculture systems.

5.
FASEB J ; 38(10): e23664, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38775797

RESUMEN

Adipogenesis, a pivotal cellular process involving the differentiation of mesenchymal stem cells (MSCs) to mature adipocytes, plays a significant role in various physiological functions. Dysregulation of adipogenesis is implicated in conditions such as obesity. However, the complete molecular understanding of adipogenesis remains elusive. This study aimed to uncover the novel role of lamina-associated polypeptide 2 alpha (LAP2α) in human adipose-derived stem cells (hASCs) adipogenesis and its impact on high-fat diet (HFD)-induced obesity and associated metabolic disturbances. LAP2α expression was assessed during the adipogenic differentiation of hASCs using RT-qPCR and western blotting. The functional role of LAP2α in adipogenesis was explored both in vitro and in vivo through loss- and gain-of-function studies. Moreover, mice with HFD-induced obesity received lentivirus injection to assess the effect of LAP2α knockdown on fat accumulation. Molecular mechanisms underlying LAP2α in adipogenic differentiation were investigated using RT-qPCR, Western blotting, immunofluorescence staining, and Oil Red O staining. LAP2α expression was upregulated during hASCs adipogenic differentiation. LAP2α knockdown hindered adipogenesis, while LAP2α overexpression promoted adipogenic differentiation. Notably, LAP2α deficiency resisted HFD-induced obesity, improved glucose intolerance, mitigated insulin resistance, and prevented fatty liver development. Mechanistically, LAP2α knockdown attenuated signal transducer and activator of transcription 3 (STAT3) activation by reducing the protein level of phosphorylated STAT3. A STAT3 activator (Colivelin) counteracted the negative impact of LAP2α deficiency on hASCs adipogenic differentiation. Taken together, our current study established LAP2α as a crucial regulator of hASCs adipogenic differentiation, unveiling a new therapeutic target for obesity prevention.


Asunto(s)
Adipogénesis , Dieta Alta en Grasa , Células Madre Mesenquimatosas , Obesidad , Humanos , Dieta Alta en Grasa/efectos adversos , Obesidad/metabolismo , Obesidad/genética , Obesidad/etiología , Animales , Ratones , Células Madre Mesenquimatosas/metabolismo , Masculino , Diferenciación Celular , Ratones Endogámicos C57BL , Tejido Adiposo/metabolismo , Tejido Adiposo/citología , Adipocitos/metabolismo , Células Cultivadas , Técnicas de Silenciamiento del Gen , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/genética , Proteínas de Unión al ADN , Proteínas de la Membrana
6.
Artículo en Inglés | MEDLINE | ID: mdl-38569482

RESUMEN

Setting 7 subsection in abstract Objectives: Necroptosis, a form of programmed cell death, can occur in the placenta of patients with preeclampsia (PE). Hydrogen sulfide (H2S) can inhibit necroptosis of human umbilical vein endothelial cells under the high-glucose-induced injury. Whether H2S can protect trophoblasts against necroptosis underlying PE has not been elucidated. This study was aimed to explore the protective role of H2S in trophoblast cells against necroptosis underlying PE. DESIGN: This is an in vitro experimental study. PARTICIPANTS: A total of 10 pregnant women with severe preeclampsia (PE) and 10 matched control normotensive pregnant women were included. The placenta tissues were extracted from participators. The human JEG-3 trophoblasts were commercially available. METHODS: The expression and localization of necrotic proteins were assayed in human placenta samples and the effect of necrotic cell death on the proliferation and apoptosis of human JEG-3 trophoblasts was evaluated. The component expressions of inflammatory cytokine and p38MAPK signaling pathway were measured in samples pretreated with or without NaHS (H2S donor) and SB203580 (p38 inhibitor). RESULTS: RIPA1, RIPA3, and p-p38 levels were significantly higher in PE placental tissue, whereas cystathionine-ß-synthase expression was decreased. In JEG-3 trophoblasts, necroptosis increased apoptotic cell numbers, suppressed cell proliferation, increased inflammatory cytokine expression, and increased p38MAPK activation, which can be prevented by NaHS. LIMITATIONS: In the present study, we did not provide sufficient evidence that necroptosis was a part of the pathogenesis of preeclampsia. CONCLUSIONS: we proposed the putative role of necroptosis in early-onset PE, reflected by the blockage of caspase-8/3 and increased expression of RIPA1, and RIPA3 in PE placenta tissues. Furthermore, we demonstrated that exogenous H2S protected cytotrophoblasts against CER-induced necroptosis via the p38MAPK pathway.

7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(1): 9-16, 2024 Feb 18.
Artículo en Chino | MEDLINE | ID: mdl-38318890

RESUMEN

OBJECTIVE: To explore the effect of ubiquitin-specific protease 42 (USP42) on osteogenic differentiation of human adipose-derived stem cells (hASCs) in vivo and in vitro. METHODS: A combination of experiments was carried out with genetic depletion of USP42 using a lentiviral strategy. Alkaline phosphatase (ALP) staining and quantification, alizarin red S (ARS) staining and quantification were used to determine the osteogenic differentiation ability of hASCs under osteogenic induction between the experimental group (knockdown group and overexpression group) and the control group. Quantitative reverse transcription PCR (qRT-PCR) was used to detect the expression levels of osteogenesis related genes in the experimental group and control group, and Western blotting was used to detect the expression levels of osteogenesis related proteins in the experimental group and control group. Nude mice ectopic implantation experiment was used to evaluate the effect of USP42 on the osteogenic differentiation of hASCs in vivo. RESULTS: The mRNA and protein expressions of USP42 in knockdown group were significantly lower than those in control group, and those in overexpression group were significantly higher than those in control group. After 7 days of osteogenic induction, the ALP activity in the knockdown group was significantly higher than that in the control group, and ALP activity in overexpression group was significantly lower than that in control group. After 14 days of osteogenic induction, ARS staining was significantly deeper in the knockdown group than in the control group, and significantly lighter in overexpression group than in the control group. The results of qRT-PCR showed that the mRNA expression levels of ALP, osterix (OSX) and collagen type Ⅰ (COLⅠ) in the knockdown group were significantly higher than those in the control group after 14 days of osteogenic induction, and those in overexpression group were significantly lower than those in control group. The results of Western blotting showed that the expression levels of runt-related transcription factor 2 (RUNX2), OSX and COLⅠ in the knockout group were significantly higher than those in the control group at 14 days after osteogenic induction, while the expression levels of RUNX2, OSX and COLⅠ in the overexpression group were significantly lower than those in the control group. Hematoxylin-eosin staining of subcutaneous grafts in nude mice showed that the percentage of osteoid area in the knockdown group was significantly higher than that in the control group. CONCLUSION: Knockdown of USP42 can significantly promote the osteogenic differentiation of hASCs in vitro and in vivo, and overexpression of USP42 significantly inhibits in vivo osteogenic differentiation of hASCs, and USP42 can provide a potential therapeutic target for bone tissue engineering.


Asunto(s)
Subunidad alfa 1 del Factor de Unión al Sitio Principal , Osteogénesis , Tioléster Hidrolasas , Animales , Humanos , Ratones , Tejido Adiposo/citología , Diferenciación Celular/genética , Células Cultivadas , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Ratones Desnudos , Osteogénesis/genética , ARN Mensajero/metabolismo , Células Madre/metabolismo , Proteasas Ubiquitina-Específicas/genética , Tioléster Hidrolasas/metabolismo
8.
Zhongguo Fei Ai Za Zhi ; 26(11): 843-850, 2023 Nov 20.
Artículo en Chino | MEDLINE | ID: mdl-38061886

RESUMEN

BACKGROUND: The relationship between quality of life at three months after lung cancer surgery and different surgical approaches is remains unclear. This study aimed to compare the quality of life of patients three months after uniportal and multiportal thoracoscopic lobectomy. METHODS: Data from patients who underwent lung surgery at the Department of Thoracic Surgery, Sichuan Cancer Hospital between April 2021 and October 2021 were collected. The European Organization for Research and Treatment of Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) and Quality of Life Questionnaire-Lung Cancer 29 (EORTC QLQ-LC29) were used to collect quality of life data of the patients. Potential confounding factors in the baseline data were included in a multivariate regression model for adjustment, and the quality of life of the two groups three months postoperatively was compared with traditional clinical outcomes. RESULTS: A total of 130 lung cancer patients were included, with 57 males (43.8%) and 73 females (56.2%), and an average age of (57.1±9.5) yr. In the baseline data of the two groups, there was a statistical difference in the number of chest drainage tubes placed (P<0.001). After adjustment with the regression model, at three months postoperatively, there were no significant differences in all symptoms and functional status scores between the two groups (all P>0.05). The multiportal group had longer surgery time (120.0 min vs 85.0 min, P=0.001), postoperative hospital stay (6.0 d vs 4.0 d, P=0.020), and a higher incidence of early ≥ grade 2 complications (39.0% vs 10.1%, P=0.011) compared to the uniportal group. CONCLUSIONS: Patients undergoing uniportal and multiportal thoracoscopic lobectomy have similar quality of life at three months postoperatively. The uniportal group may have certain advantages in terms of traditional clinical outcome indicators such as operation time, postoperative hospital stay, and early postoperative complications.


Asunto(s)
Neoplasias Pulmonares , Masculino , Femenino , Humanos , Neoplasias Pulmonares/cirugía , Calidad de Vida , Cirugía Torácica Asistida por Video/efectos adversos , Neumonectomía/efectos adversos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos
9.
Medicine (Baltimore) ; 102(41): e35243, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37832095

RESUMEN

The ongoing ENPOWER study exploring the efficacy and safety of the recombinant human endostatin (endostar) combined with programmed cell death 1 antibody sintilimab and chemotherapy showed encouraging efficacy and safety in advanced non-squamous non-small cell lung cancer. To evaluate the real-world efficacy and safety of endostar combined with immune checkpoint inhibitor and chemotherapy (EIC) for advanced non-squamous non-small cell lung cancer patients negative for actionable molecular biomarkers (NSCLCnm), patients with advanced NSCLCnm hospitalized to Zhejiang Provincial People's Hospital from January 2020 to December 2022 were screened for eligibility. The included patients were analyzed for the objective response rate (ORR) and disease control rate (DCR). The pre- and posttreatment expression levels of serum tumor associated biomarkers, chemokines and subpopulations of immune cells in peripheral blood were compared. For the 31 patients with advanced NSCLCnm treated with EIC, the median follow-up and treatment cycles were 18.0 months and 4, respectively. The ORR and DCR were 38.7% and 90.3%, respectively. For those who received EIC as first-line treatment, the ORR and DCR were 63.2% and 94.7%, respectively. EIC significantly decreased expression levels of carcinoma antigen 125, carcinoma embryonic antigen and cytokeratin 19 (P<0.05) in patients who were partial remission or stable disease. Among the 31 patients, 27 (87.1%) experienced at least 1 treatment-related adverse events, and 13 (41.9%) had the treatment-related adverse events of grade 3 or higher. No antiangiogenesis-related adverse events were observed. The current study showed that EIC was potentially effective for patients with NSCLCnm, especially when used as first-line therapy, and well tolerated.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Antígeno B7-H1/uso terapéutico , Biomarcadores de Tumor , Carcinoma de Pulmón de Células no Pequeñas/patología , Endostatinas , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Pulmonares/patología , Receptor de Muerte Celular Programada 1/uso terapéutico
10.
Reprod Sci ; 30(12): 3661-3676, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37580647

RESUMEN

Cervical cancer (CC) is one of the most prevalent gynecological malignancies. The rate of mortality and morbidity among patients with CC is high. Cellular senescence is involved in tumorigenesis as well as in the cancer progression. However, the involvement of cellular senescence in CC development is still unclear and requires further investigation. In this study, we retrieved data on cellular senescence-related genes (CSRGs) from the "CellAge" Database. We used the TCGA-CESC and CGCI-HTMCP-CC datasets as the training and validation sets, respectively. Finally, a signature was constructed using "univariate" and "Least Absolute Shrinkage and Selection Operator" (LASSO) Cox regression analysis, which contains eight CSRGs. Using this signature, we calculated the risk scores of all patients in the training and validation cohorts and categorized them into the low-risk group (LR-G) and the high-risk group (HR-G). Results showed that, compared to patients in the HR-G, those in the LR-G demonstrated a more positive clinical prognosis, more abundant immune cell infiltrations, and a more active immune response. The signature could also modulate the expression of SASP factors. In vitro studies showed an increased expression of SERPINE1 and IL-1α genes included in the signature in CC cells and tissues. Our findings help to deepen our insights into the etiology of CC, which could be beneficial for prognostic prediction and immunotherapy in clinical practice.


Asunto(s)
Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/terapia , Senescencia Celular , Inmunoterapia , Transformación Celular Neoplásica , Factores de Riesgo , Pronóstico
11.
Front Immunol ; 14: 1148425, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37559729

RESUMEN

Immune checkpoint inhibitors (ICIs) are an integral antitumor therapy for many malignancies. Most patients show very good tolerability to ICIs; however, serious immune-related adverse events (irAEs) with ICIs have been well documented and prevent some patients from continuing ICIs or even become the direct cause of patient death. Cytopenia is a rare irAE but can be life-threatening. Here, we present the case of a 66-year-old male patient with metastatic lung adenocarcinoma who received two doses of chemotherapy + PD-1 antibody tislelizumab and developed pancytopenia after each dose. Although the first episode of pancytopenia resolved with a treatment regimen of granulocyte colony-stimulating factor (G-CSF), thrombopoietin (TPO), and red blood cell and platelet transfusion, the second episode showed extreme resistance to these treatments and improved only after the administration of steroids. His second pancytopenia episode resolved after a long course of treatment with methylprednisolone, G-CSF, TPO, hetrombopag and multiple red blood cell and platelet transfusions. However, he suffered a cerebral infarction when his platelet count was in the normal range and gradually recovered 1 week later. This case highlights the importance of the early recognition and management of hematological irAEs.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Pancitopenia , Masculino , Humanos , Anciano , Pancitopenia/inducido químicamente , Pancitopenia/diagnóstico , Adenocarcinoma del Pulmón/complicaciones , Adenocarcinoma del Pulmón/tratamiento farmacológico , Factor Estimulante de Colonias de Granulocitos , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Infarto Cerebral
12.
J Hazard Mater ; 458: 131974, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37406521

RESUMEN

Early evidence has elucidated that the spread of antibiotic (ARGs) and metal resistance genes (MRGs) are mainly attributed to the selection pressure in human-influenced environments. However, whether and how biotic and abiotic factors mediate the distribution of ARGs and MRGs in mangrove sediments under natural sedimentation is largely unclear. Here, we profiled the abundance and diversity of ARGs and MRGs and their relationships with sedimental microbiomes in 0-100 cm mangrove sediments. Our results identified multidrug-resistance and multimetal-resistance as the most abundant ARG and MRG classes, and their abundances generally decreased with the sediment depth. Instead of abiotic factors such as nutrients and antibiotics, the bacterial diversity was significantly negatively correlated with the abundance and diversity of resistomes. Also, the majority of resistance classes (e.g., multidrug and arsenic) were carried by more diverse bacterial hosts in deep layers with low abundances of resistance genes. Together, our results indicated that bacterial diversity was the most important biotic factor driving the vertical profile of ARGs and MRGs in the mangrove sediment. Given that there is a foreseeable increasing human impact on natural environments, this study emphasizes the important role of biodiversity in driving the abundance and diversity of ARGs and MRGs.


Asunto(s)
Genes Bacterianos , Microbiota , Humanos , Bacterias/genética , Antibacterianos
13.
Materials (Basel) ; 16(12)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37374472

RESUMEN

The densification of a SiCp/Al-Fe-V-Si billet was achieved by reducing the pores and oxide film between the particles by rolling. The wedge pressing method was used to improve the formability of the composite after jet deposition. The key parameters, mechanisms, and laws of wedge compaction were studied. The results showed that the pass rate was reduced by 10 to 15 percent when using steel molds during the wedge pressing process if the distance between the two ends of the billet was about 10 mm, which was beneficial to improve the compactness and formability of the billet. The density and stress of the surface of the material were higher than those of the interior, where the distribution of density and stress tended to be uniform as the overall volume of the material shrank. During the wedge extrusion process, the material in the preforming area was thinned along the thickness direction, while the material in the main deformation area was lengthened along the length direction. Under plane strain conditions, the wedge formation of spray-deposited composites follows the plastic deformation mechanism of porous metals. The true relative density of the sheet was higher than the calculated value during the initial stamping phase, but was lower than the calculated value when the true strain exceeded 0.55. This was due to the accumulation and fragmentation of SiC particles, which made the pores difficult to remove.

14.
Front Endocrinol (Lausanne) ; 14: 1129657, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37223018

RESUMEN

Background: Premature ovarian insufficiency (POI) is one of the most common causes of female infertility and the etiology is highly heterogeneous. Most cases are idiopathic and the pathogenesis remains unclear. Previous studies proved that the immune system plays a crucial role in POI. However, the precise role of immune system remains unclear. This study aimed to analyze the characteristics of peripheral blood mononuclear cells (PBMC) from patients with POI by single-cell RNA sequencing (scRNA-seq) and to explore the potential involvement of immune response in idiopathic POI. Methods: PBMC was collected from three normal subjects and three patients with POI. PBMC was subjected to scRNA-seq to identify cell clusters and differently expressed genes (DEGs). Enrichment analysis and cell-cell communication analysis were performed to explore the most active biological function in the immune cells of patients with POI. Results: In total, 22 cell clusters and 10 cell types were identified in the two groups. Compared with normal subjects, the percentage of classical monocytes and NK cells was decreased, the abundance of plasma B cells was increased, and CD4/CD8 ratio was significantly higher in POI. Furthermore, upregulation of IGKC, IFITM1, CD69, JUND and downregulation of LYZ, GNLY, VCAN, and S100A9 were identified, which were enriched in NK cell-mediated cytotoxicity, antigen processing and presentation, and IL-17 signaling pathway. Among them, IGHM and LYZ were respectively the most significantly upregulated and downregulated genes among all cell clusters of POI. The strength of cell-cell communication differed between the healthy subjects and patients with POI, and multiple signaling pathways were assessed. The TNF pathway was found to be unique in POI with classical monocytes being the major target and source of TNF signaling. Conclusions: Dysfunction of cellular immunity is related to idiopathic POI. Monocytes, NK cells, and B cells, and their enriched differential genes may play a role in the development of idiopathic POI. These findings provide novel mechanistic insight for understanding the pathogenesis of POI.


Asunto(s)
Enfermedades del Sistema Inmune , Menopausia Prematura , Insuficiencia Ovárica Primaria , Humanos , Femenino , Leucocitos Mononucleares , Insuficiencia Ovárica Primaria/genética , Análisis de Secuencia de ARN
15.
Res Sq ; 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37131778

RESUMEN

Cervical cancer (CC) is among the most prevalent gynaecological malignancy. The rate of mortality and morbidity of patients with CC is high. Cellular senescence is involved in tumorigenesis as well as cancer progression. However, the involvement of cellular senescence in CC development is still unclear and requires further investigation. We retrieved data on cellular senescence-related genes (CSRGs) from the "CellAge" Database. We used TCGA-CESC and the CGCI-HTMCP-CC datasets as the training and validation sets, respectively. Eight CSRGs signatures based on the data extracted from these sets were constructed using "univariate" and "Least Absolute Shrinkage and Selection Operator Cox regression analyses". Using this model, we calculated the risk scores of all patients in the training and validation cohort and categorised these patients into the low-risk group (LR-G) and the high-risk group (HR-G). Finally, compared to patients in the HR-G, CC patients in the LR-G demonstrated a more positive clinical prognosis; the expression of senescence-associated secretory phenotype (SASP) markers and immune cell infiltration was higher, and these patients had more active immune responses. In vitro studies showed increased SERPINE1 and IL-1α ((genes included in the signature) expression in CC cells and tissues. The eight-gene prognostic signatures could modulate the expression of SASP factors and the tumour immune micro-environment (TIME). It could be used as a reliable biomarker for predicting the patient's prognosis and response to immunotherapy in CC.

16.
Microbiome ; 11(1): 71, 2023 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-37020239

RESUMEN

BACKGROUND: Mangrove ecosystems are considered as hot spots of biogeochemical cycling, yet the diversity, function and coupling mechanism of microbially driven biogeochemical cycling along the sediment depth of mangrove wetlands remain elusive. Here we investigated the vertical profile of methane (CH4), nitrogen (N) and sulphur (S) cycling genes/pathways and their potential coupling mechanisms using metagenome sequencing approaches. RESULTS: Our results showed that the metabolic pathways involved in CH4, N and S cycling were mainly shaped by pH and acid volatile sulphide (AVS) along a sediment depth, and AVS was a critical electron donor impacting mangrove sediment S oxidation and denitrification. Gene families involved in S oxidation and denitrification significantly (P < 0.05) decreased along the sediment depth and could be coupled by S-driven denitrifiers, such as Burkholderiaceae and Sulfurifustis in the surface sediment (0-15 cm). Interestingly, all S-driven denitrifier metagenome-assembled genomes (MAGs) appeared to be incomplete denitrifiers with nitrate/nitrite/nitric oxide reductases (Nar/Nir/Nor) but without nitrous oxide reductase (Nos), suggesting such sulphide-utilizing groups might be an important contributor to N2O production in the surface mangrove sediment. Gene families involved in methanogenesis and S reduction significantly (P < 0.05) increased along the sediment depth. Based on both network and MAG analyses, sulphate-reducing bacteria (SRB) might develop syntrophic relationships with anaerobic CH4 oxidizers (ANMEs) by direct electron transfer or zero-valent sulphur, which would pull forward the co-existence of methanogens and SRB in the middle and deep layer sediments. CONCLUSIONS: In addition to offering a perspective on the vertical distribution of microbially driven CH4, N and S cycling genes/pathways, this study emphasizes the important role of S-driven denitrifiers on N2O emissions and various possible coupling mechanisms of ANMEs and SRB along the mangrove sediment depth. The exploration of potential coupling mechanisms provides novel insights into future synthetic microbial community construction and analysis. This study also has important implications for predicting ecosystem functions within the context of environmental and global change. Video Abstract.


Asunto(s)
Desulfovibrio , Microbiota , Metano/metabolismo , Nitrógeno/metabolismo , Azufre/metabolismo , Sulfuros , Sedimentos Geológicos/microbiología
17.
Front Cell Dev Biol ; 10: 1033223, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36340031

RESUMEN

The ubiquitin-proteasome system is an important pathway for mediating posttranslational modification and protein homeostasis and exerts a wide range of functions in diverse biological processes, including stem cell differentiation, DNA repair, and cell cycle regulation. Many studies have shown that ubiquitination modification plays a critical role in regulating the osteogenic differentiation of stem cells and bone formation through various mechanisms. This review summarizes current progress on the effects and mechanisms of ubiquitin modification on transcription factors and signaling pathways involved in osteogenic differentiation. Moreover, the review highlights the latest advances in the clinical application of drugs in bone tissue engineering. A thorough understanding of ubiquitin modifications may provide promising therapeutic targets for stem cell-based bone tissue engineering.

18.
Gynecol Endocrinol ; 38(9): 705-712, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35970196

RESUMEN

OBJECTIVE: We aimed to investigate the correlation between blood homocysteine (Hcy) levels and pre-eclampsia (PE) risk in pregnant women. METHODS: Related articles were searched using PubMed, Embase, and Web of Science databases. Methodological quality of included studies was evaluated using the Newcastle-Ottawa Quality Assessment Scale (NOS). Cochran's Q and I2 tests were used to evaluate heterogeneity. Egger's test was used to evaluate publication bias. A sensitivity analysis was performed to test stability of the results using a one-by-one elimination method. Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) was used to assess certainty of evidence. RESULTS: Nine studies (4384 PE and 26021 non-PE patients) were included in the meta-analysis. The methodology of them was of good quality, with NOS scores of 5-8. However, there was a significant heterogeneity among included studies. Therefore, the random effect model was generated and combined results suggested a significant association between increased level of Hcy in pregnant women and PE risk. Although a significant publication bias was found in the current study with a P value of 0.006 in the Egger test, sensitivity analysis showed that the combined results were stable and did not vary significantly from any single study. However, the GRADE evidence quality was very low, which may lower the recommendation of pooled results. CONCLUSIONS: Increased levels of Hcy in maternal blood were significantly associated with the risk of PE, but low certainty of evidence need to be improved by more high-quality studies.


Asunto(s)
Preeclampsia , Femenino , Homocisteína , Humanos , Preeclampsia/epidemiología , Embarazo , Mujeres Embarazadas
19.
Antioxidants (Basel) ; 11(8)2022 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-36009224

RESUMEN

We have previously demonstrated that placental 11ß-hydroxysteroid dehydrogenase type 2 (11ß-HSD2) dysfunction contributes to PE pathogenesis. We sought to elucidate molecular mechanisms underlying 11ß-HSD2 dysfunction-induced PE and to seek potential therapeutic targets using a 11ß-HSD2 dysfunction-induced PE-like rat model as well as cultured extravillous trophoblasts (EVTs) since PE begins with impaired function of EVTs. In 11ß-HSD2 dysfunction-induced PE-like rat model, we revealed that placental mitochondrial dysfunction occurred, which was associated with mitDNA instability and impaired mitochondrial dynamics, such as decreased optic atrophy 1 (OPA1) expression. MitoTEMPO treatment significantly alleviated the hallmark of PE-like features and improved mitDNA stability and mitochondrial dynamics in the placentas of rat PE-like model. In cultured human EVTs, we found that 11ß-HSD2 dysfunction led to mitochondrial dysfunction and disrupted mtDNA stability. MitoTEMPO treatment improved impaired invasion and migration induced by 11ß-HSD2 dysfunction in cultured EVTs. Further, we revealed that OPA1 was one of the key factors that mediated 11ß-HSD2 dysfunction-induced excess ROS production, mitochondrial dysfunction and mtDNA reduction. Our data indicates that 11ß-HSD2 dysfunction causes mitochondrial dysfunctions, which impairs trophoblast function and subsequently results in PE development. Our study immediately highlights that excess ROS is a potential therapeutic target for PE.

20.
Materials (Basel) ; 15(13)2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35806755

RESUMEN

Surface-functionalized polymer composites with spherical particles as fillers offer great qualities and have been widely employed in applications of sensors, pharmaceutical industries, anti-icing, and flexible electromagnetic interference shielding. The directional migration and dispersion theory of magnetic microparticles in polypropylene (PP)-matrix magnetic composites must be studied to better acquire the functional surface with remarkable features. In this work, a novel simulation model based on multi-physical field coupling was suggested to analyze the directed migration and distribution of magnetic ferroferric oxide (Fe3O4) particles in injection molding assisted by an external magnetic field using COMSOL Multiphysics® software. To accurately introduce rheological phenomena of polymer melt into the simulation model, the Carreau model was used. Particle size, magnetic field intensity, melt viscosity, and other parameters impacting particle directional motion were discussed in depth. The directional distribution of particles in the simulation model was properly assessed and confirmed by experiment results. This model provides theoretical support for the control, optimization, and investigation of the injection-molding process control of surface-functionalized polymer composites.

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