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1.
Cytotherapy ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38625072

RESUMO

BACKGROUND AIMS: Chimeric antigen receptor-T (CAR-T) cells have exhibited remarkable efficacy in treating refractory or relapsed multiple myeloma (R/R MM). Although obesity has a favorable value in enhancing the response to immunotherapy, less is known about its predictive value regarding the efficacy and prognosis of CAR-T cell immunotherapy. METHODS: We conducted a retrospective study of 111 patients with R/R MM who underwent CAR-T cell treatment. Using the body mass index (BMI) classification, the patients were divided into a normal-weight group (73/111) and an overweight group (38/111). We investigated the effect of BMI on CAR-T cell therapy outcomes in patients with R/R MM. RESULTS: The objective remission rates after CAR-T cell infusion were 94.7% and 89.0% in the overweight and normal-weight groups, respectively. The duration of response and overall survival were not significant difference between BMI groups. Compared to normal-weight patients, overweight patients had an improved median progression-free survival. There was no significant difference in cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome between the subgroups. In terms of hematological toxicity, the erythrocyte, hemoglobin, platelet, leukocyte and neutrophil recovery was accelerated in the overweight group. Fewer patients in the overweight group displayed moderate percent CD4 and CD4/CD8 ratios compared to the normal-weight group. Furthermore, the percent CD4 ratios were positively correlated with the levels of cytokines [interleukin-2 (IL-2) (day 14), interferon gamma (IFN-γ) (day 7) and tumor necrosis factor alpha (TNF-α) (days 14 and 21)] after cells infusion. On the other hand, BMI was positively associated with the levels of IFN-γ (day 7) and TNF-α (days 14 and 21) after CAR-T cells infusion. CONCLUSIONS: Overall, this study highlights the potential beneficial effect of a higher BMI on CAR-T cell therapy outcomes.

2.
Zhongguo Zhong Yao Za Zhi ; 49(4): 951-960, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621902

RESUMO

The chemical constituents of ethyl acetate from Hypericum himalaicum were isolated by silica gel column chromatography, gel column chromatography, and high-performance liquid chromatography. The structure of the isolated compounds was identified by modern spectral techniques(NMR, MS, IR, and UV), and the potential anti-inflammatory targets and action pathways were analyzed and predicted by network pharmacology and molecular docking methods.Ten compounds were isolated from H. himalaicum and identified as 5,9,11-trihydroxy-3,3-dimethyl-3H,8H-benzo[6,7][1,4]dioxepino[2,3-f]chromen-8-one(1), betulinic acid(2), demethyltorosaflavone C(3), kaempferol(4), quercetin(5), hyperwightin B(6), toxyloxanthone B(7), 1,7-dihydroxy-xanthone(8), emodin(9), and 1,7-dihydroxy-4-methoxy-xanthone(10). Among them, compound 1 was a new compound, and compounds 2-10 were isolated from H. himalaicum for the first time. Network pharmacology screened 60 key anti-inflammatory targets. By acting on TNF, AKT1, CASP3, and other key targets, involving PI3K-AKT signaling pathway, IL-17 signaling pathway, VEGF signaling pathway, MAPK signaling pathway, and other signaling pathways, and phosphorylation, cell migration and movement, protein tyrosine kinase, and other biological processes were regulated to achieve anti-inflammatory effects. The results of molecular docking show that the above components have good binding properties with the core targets.


Assuntos
Medicamentos de Ervas Chinesas , Hypericum , Xantonas , Farmacologia em Rede , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases , Anti-Inflamatórios/farmacologia , Proteínas Proto-Oncogênicas c-akt
3.
Phytomedicine ; 128: 155385, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38569292

RESUMO

BACKGROUND: Xianlian Jiedu Decoction (XLJDD) has been used for the treatment of colorectal cancer (CRC) for several decades because of the prominent efficacy of the prescription. Despite the clear clinical efficacy of XLJDD, the anti-CRC mechanism of action is still unclear. PURPOSE: The inhibitory effect and mechanism of XLJDD on CRC were investigated in the azoxymethane/dextran sulfate sodium (AOM/DSS)-induced mice. METHODS: The AOM/DSS-induced mice model was adopted to evaluate the efficacy after administering the different doses of XLJDD. The therapeutic effects of XLJDD in treating AOM/DSS-induced CRC were investigated through histopathology, immunofluorescence and ELISA analysis methods. In addition, metabolomics profile and 16S rRNA analysis were used to explore the effective mechanisms of XLJDD on CRC. RESULTS: The results stated that the XLJDD reduced the number of tumor growth on the inner wall of the colon and the colorectal weight/length ratio, and suppressed the disease activity index (DAI) score, meanwhile XLJDD also increased body weight, colorectal length, and overall survival rate. The treatment of XLJDD also exhibited the ability to lower the level of inflammatory cytokines in serum and reduce the expression levels of ß-catenin, COX-2, and iNOS protein in colorectal tissue. The findings suggested that XLJDD has anti-inflammatory properties and may provide relief for those suffering from inflammation-related conditions. Mechanistically, XLJDD improved gut microbiota dysbiosis and associated metabolic levels of short chain fatty acids (SCFAs), sphingolipid, and glycerophospholipid. This was achieved by reducing the abundance of Turicibacter, Clostridium_sensu_stricto_1, and the levels of sphinganine, LPCs, and PCs. Additionally, XLJDD increased the abundance of Enterorhabdus and Alistipes probiotics, as well as the content of butyric acid and isovaleric acid. CONCLUSION: The data presented in this article demonstrated that XLJDD can effectively inhibit the occurrence of colon inner wall tumors by reducing the level of inflammation and alleviating intestinal microbial flora imbalance and metabolic disorders. It provides a scientific basis for clinical prevention and treatment of CRC.

4.
J Am Chem Soc ; 146(16): 11083-11094, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38619978

RESUMO

Molecular lanthanide (Ln) complexes are promising candidates for the development of next-generation quantum technologies. High-symmetry structures incorporating integer spin Ln ions can give rise to well-isolated crystal field quasi-doublet ground states, i.e., quantum two-level systems that may serve as the basis for magnetic qubits. Recent work has shown that symmetry lowering of the coordination environment around the Ln ion can produce an avoided crossing or clock transition within the ground doublet, leading to significantly enhanced coherence. Here, we employ single-crystal high-frequency electron paramagnetic resonance spectroscopy and high-level ab initio calculations to carry out a detailed investigation of the nine-coordinate complexes, [HoIIIL1L2], where L1 = 1,4,7,10-tetrakis(2-pyridylmethyl)-1,4,7,10-tetraaza-cyclododecane and L2 = F- (1) or [MeCN]0 (2). The pseudo-4-fold symmetry imposed by the neutral organic ligand scaffold (L1) and the apical anionic fluoride ion generates a strong axial anisotropy with an mJ = ±8 ground-state quasi-doublet in 1, where mJ denotes the projection of the J = 8 spin-orbital moment onto the ∼C4 axis. Meanwhile, off-diagonal crystal field interactions give rise to a giant 116.4 ± 1.0 GHz clock transition within this doublet. We then demonstrate targeted crystal field engineering of the clock transition by replacing F- with neutral MeCN (2), resulting in an increase in the clock transition frequency by a factor of 2.2. The experimental results are in broad agreement with quantum chemical calculations. This tunability is highly desirable because decoherence caused by second-order sensitivity to magnetic noise scales inversely with the clock transition frequency.

5.
Bioresour Technol ; 400: 130697, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38614145

RESUMO

Effects of a phosphorus-solubilizing bacteria (PSB) Bacillus megatherium on growth and lipid production of Chlorella sorokiniana were investigated in synthesized swine wastewater with dissolved inorganic phosphorus (DIP), insoluble inorganic phosphorus (IIP), and organic phosphorus (OP). The results showed that the PSB significantly promoted the algal growth in OP and IIP, by 1.10 and 1.78-fold, respectively. The algal lipid accumulation was also greatly triggered, respectively by 4.39, 1.68, and 1.38-fold in DIP, IIP, and OP. Moreover, compared with DIP, OP improved the oxidation stability of algal lipid by increasing the proportion of saturated fatty acids (43.8 % vs 27.9 %), while the PSB tended to adjust it to moderate ranges (30.2-41.6 %). Further, the transcriptome analysis verified the OP and/or PSB-induced up-regulated genes involving photosynthesis, lipid metabolism, signal transduction, etc. This study provided novel insights to enhance microalgae-based nutrient removal combined with biofuel production in practical wastewater, especially with complex forms of phosphorus.

6.
Nat Commun ; 15(1): 3371, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643278

RESUMO

Despite the high therapeutic response achieved with B-cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T-cell therapy in relapsed and refractory multiple myeloma (R/R MM), primary resistance and relapse exist with single-target immunotherapy. Here, we design bispecific BC19 CAR T cells targeting BCMA/CD19 and evaluate antimyeloma activity in vitro and in vivo. Preclinical results indicate that BC19 CAR specifically recognize target antigens, and BC19 CAR T cells mediate selective killing of BCMA or CD19-positive cancer cells. BC19 CAR T cells also exhibit potent antigen-specific anti-tumor activity in xenograft mouse models. We conduct an open-label, single-arm, phase I/II study of BC19 CAR T cells in 50 patients with R/R MM (ChiCTR2000033567). The primary endpoint was safety. BC19 CAR T cells are well tolerated with grade 3 or higher cytokine release syndrome in 8% of patients and grade 1 neurotoxic events in 4% of patients, which meet the pre-specified primary endpoint. Secondary endpoints include overall response rate (92%), median progression-free survival (19.7 months), median overall survival (19.7 months) and median duration of response (not reached). Our study demonstrates that bispecific BC19 CAR T cells are feasible, safe and effective in treating patients with R/R MM.


Assuntos
Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Humanos , Animais , Camundongos , Mieloma Múltiplo/patologia , Imunoterapia Adotiva/métodos , Antígeno de Maturação de Linfócitos B , Recidiva Local de Neoplasia , Antígenos CD19
7.
ACS Omega ; 9(15): 17533-17540, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38645326

RESUMO

Epoxy resin is extensively applied in the electronics and electrical fields because of its outstanding comprehensive performance. However, the low thermal conductivity (TC) limits its application in thermal interface materials. In the present work, epoxy-based hybrid composites with high TC were prepared by using expanded graphite (EG) and copper (Cu) nanoparticles as thermally conductive hybrid fillers via hot blending and compression-curing processes. Additionally, the influence of the Cu content on the thermal properties, mechanical properties, and morphology of each epoxy/EG/Cu composite was investigated. According to the results, the epoxy/EG/Cu composite showed a maximum TC of 9.74 W/(m·K) at a fixed EG content of 60 wt % owing to the addition of 10 wt % Cu. After the addition of 10 wt % Cu, the flexural strength, flexural modulus, and impact strengths of epoxy/EG/Cu composites were improved from 27.9 MPa, 9.72 GPa, and 0.81 kJ/m2 to 37.5 MPa, 10.88 GPa, and 0.91 kJ/m2, respectively. Hence, this study offers a feasible strategy for the design of epoxy hybrid composites with excellent TC that can be applied to thermal interface materials.

8.
Food Chem ; 450: 139318, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38613965

RESUMO

For texture control in plant-meat alternatives, the interrelationship between apparent characteristics and chemical bonds in high-fiber formulations remains unclear. The influence of mulberry leaf powder on apparent characteristics and chemical bonds of raw materials, block and strip products at addition amounts of 0.5-25% was analyzed. The results showed that 8% addition significantly increased the chewiness of the block by 98.12%. The strips' texture shows a downward trend, and the processing produced more redness and color difference. Additives promoted the formation of voids, lamellar and filamentous structures, and the strip produced more striped structures. Disulfide bonds significantly increased in the block, and the ß-turn in the secondary structure enhanced by 12.20%. The ß-turn transformed into a ß-sheet in strips. Principal component analysis revealed that the texture improvement was associated with producing disulfide bonds and ß-turn, providing a basis for high-fiber components to improve products' apparent characteristics by chemical bonds.

9.
Cancer Immunol Immunother ; 73(6): 104, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630258

RESUMO

Few studies have reported the associations of granulocyte colony-stimulating factor (G-CSF) with cytokine release syndrome (CRS), neurotoxic events (NEs) and efficacy after chimeric antigen receptor (CAR) T-cell therapy for relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL). We present a retrospective study of 67 patients with R/R B-ALL who received anti-CD19 CAR T-cell therapy, 41 (61.2%) patients received G-CSF (G-CSF group), while 26 (38.8%) did not (non-G-CSF group). Patients had similar duration of grade 3-4 neutropenia between the two groups. The incidences of CRS and NEs were higher in G-CSF group, while no differences in severity were found. Further stratified analysis showed that the incidence and severity of CRS were not associated with G-CSF administration in patients with low bone marrow (BM) tumor burden. None of the patients with low BM tumor burden developed NEs. However, there was a significant increase in the incidence of CRS after G-CSF administration in patients with high BM tumor burden. The duration of CRS in patients who used G-CSF was longer. There were no significant differences in response rates at 1 and 3 months after CAR T-cell infusion, as well as overall survival (OS) between the two groups. In conclusion, our results showed that G-CSF administration was not associated with the incidence or severity of CRS in patients with low BM tumor burden, but the incidence of CRS was higher after G-CSF administration in patients with high BM tumor burden. The duration of CRS was prolonged in G-CSF group. G-CSF administration was not associated with the efficacy of CAR T-cell therapy.


Assuntos
Síndromes Neurotóxicas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Receptores de Antígenos Quiméricos , Humanos , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Imunoterapia Adotiva/efeitos adversos , Estudos Retrospectivos , Síndrome da Liberação de Citocina , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Terapia Baseada em Transplante de Células e Tecidos
10.
World J Gastrointest Oncol ; 16(4): 1532-1546, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38660671

RESUMO

BACKGROUND: Peutz-Jeghers syndrome (PJS) is a rare hereditary neoplastic disorder mainly associated with serine/threonine kinase 11 (STK11/LKB1) gene mutations. Preimplantation genetic testing can protect a patient's offspring from mutated genes; however, some variations in this gene have been interpreted as variants of uncertain significance (VUS), which complicate reproductive decision-making in genetic counseling. AIM: To identify the pathogenicity of two missense variants and provide clinical guidance. METHODS: Whole exome gene sequencing and Sanger sequencing were performed on the peripheral blood of patients with PJS treated at the Reproductive and Genetic Hospital of Citic-Xiangya. Software was employed to predict the protein structure, conservation, and pathogenicity of the two missense variation sites in patients with PJS. Additionally, plasmids were constructed and transfected into HeLa cells to observe cell growth. The differences in signal pathway expression between the variant group and the wild-type group were compared using western blot and immunohistochemistry. Statistical analysis was performed using one-way analysis of variance. P < 0.05 was considered statistically significant. RESULTS: We identified two missense STK11 gene VUS [c.889A>G (p.Arg297Gly) and c.733C>T (p.Leu245Phe)] in 9 unrelated PJS families who were seeking reproductive assistance. The two missense VUS were located in the catalytic domain of serine/threonine kinase, which is a key structure of the liver kinase B1 (LKB1) protein. In vitro experiments showed that the phosphorylation levels of adenosine monophosphate-activated protein kinase (AMPK) at Thr172 and LKB1 at Ser428 were significantly higher in transfected variation-type cells than in wild-type cells. In addition, the two missense STK11 variants promoted the proliferation of HeLa cells. Subsequent immunohistochemical analysis showed that phosphorylated-AMPK (Thr172) expression was significantly lower in gastric, colonic, and uterine polyps from PJS patients with missense variations than in non-PJS patients. Our findings indicate that these two missense STK11 variants are likely pathogenic and inactivate the STK11 gene, causing it to lose its function of regulating downstream phosphorylated-AMPK (Thr172), which may lead to the development of PJS. The identification of the pathogenic mutations in these two clinically characterized PJS patients has been helpful in guiding them toward the most appropriate mode of pregnancy assistance. CONCLUSION: These two missense variants can be interpreted as likely pathogenic variants that mediated the onset of PJS in the two patients. These findings not only offer insights for clinical decision-making, but also serve as a foundation for further research and reanalysis of missense VUS in rare diseases.

11.
Int J Immunogenet ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514898

RESUMO

The autophagy gene immunity-related GTPase M (IRGM) can affect the immune response against intracellular pathogens. The study was performed to determine any possible association between three IRGM single-nucleotide polymorphisms (SNPs) (rs4958842, rs4958843 and rs4958846) and chronic hepatitis B virus (HBV) infection. A total of 171 chronic HBV-infected individuals and 171 healthy controls were collected. Peripheral blood cells and Sanger sequencing were used to extract genomic DNA and determine the SNP genotypes, respectively. The C allele of rs4958843 is a risk factor for chronic HBV infection in various genetic models, including allelic, codominant and dominant models, with the following respective statistical data: allelic (T vs. C: OR = 1.371, 95% CI = 1.009-1.863, p = .043), codominant (TT vs. CC: OR = 2.137, 95% CI = 1.104-4.138, p = .024) and dominant (TT + TC vs. CC: OR = 1.976, 95% CI = 1.106-3.533, p = .021) models. The genotype and allele distributions of rs4958842 and rs4958846 showed no significant differences between chronic HBV infection patients and healthy controls. IRGM rs4958843 CC genotype carriers had significantly elevated values of alanine transaminase, aspartate transaminase alpha-fetoprotein and total bilirubin (OR = 3.467, 95%CI = 1.167-10.298), which was positively associated with the disease progression of HBV infection. Mutant allele C of IRGM rs4958843 polymorphism is associated with the risk of chronic HBV infection in the Han people in central China and contributes to the disease progression.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38457239

RESUMO

Human neural progenitor cells (hNPCs) hold promise for treating spinal cord injury. Studies to date have focused on improving their regenerative potential and therapeutic effect. Equally important is ensuring successful delivery and engraftment of hNPCs at the injury site. Unfortunately, no current imaging solution for cell tracking is compatible with long-term monitoring in vivo. The objective of this study was to apply a novel bright-ferritin magnetic resonance imaging (MRI) mechanism to track hNPC transplants longitudinally and on demand in the rat spinal cord. We genetically modified hNPCs to stably overexpress human ferritin. Ferritin-overexpressing (FT) hNPCs labeled with 0.2 mM manganese provided significant T1-induced bright contrast on in vitro MRI, with no adverse effect on cell viability, morphology, proliferation, and differentiation. In vivo, 2 M cells were injected into the cervical spinal cord of Rowett nude rats. MRI employed T1-weighted acquisitions and T1 mapping on a 3 T scanner. Conventional short-term cell tracking was performed using exogenous Mn labeling prior to cell transplantation, which displayed transient bright contrast on MRI 1 day after cell transplantation and disappeared after 1 week. In contrast, long-term cell tracking using bright-ferritin allowed on-demand signal recall upon Mn supplementation and precise visualization of the surviving hNPC graft. In fact, this new cell tracking technology identified 7 weeks post-transplantation as the timepoint by which substantial hNPC integration occurred. Spatial distribution of hNPCs on MRI matched that on histology. In summary, bright-ferritin provides the first demonstration of long-term, on-demand, high-resolution, and specific tracking of hNPCs in the rat spinal cord.

13.
Sci Rep ; 14(1): 7420, 2024 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548840

RESUMO

The ability for bacteria to form boundaries between neighboring colonies as the result of intra-species inhibition has been described for a limited number of species. Here, we report that intra-species inhibition is more common than previously recognized. We demonstrated that swimming colonies of four Escherichia coli strains and six other bacteria form inhibitory zones between colonies, which is not caused by nutrient depletion. This phenomenon was similarly observed with non-flagellated bacteria. We developed a square-streaking pattern assay which revealed that Escherichia coli BW25113 inhibits the growth of other E. coli, and surprisingly, other Gram-positive and negative bacteria, including multi-drug resistant clinical isolates. Altogether, our findings demonstrate intra-species inhibition is common and might be used by E. coli to inhibit other bacteria. Our findings raise the possibility for a common mechanism shared across bacteria for intra-species inhibition. This can be further explored for a potential new class of antibiotics.


Assuntos
Antibacterianos , Escherichia coli , Antibacterianos/farmacologia , Bactérias Gram-Positivas , Bactérias , Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana
14.
Bioresour Technol ; 399: 130604, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38499206

RESUMO

The biofilm of an engineered strain is limited by slow growth and low yield, resulting in an unsatisfactory ability to resist external stress and promote catalytic efficiency. Here, biofilms used as robust living catalysts were manipulated through dual functionalized gene regulation and carrier modification strategies. The results showed that gene overexpression regulates the autoinducer-2 activity, extracellular polymeric substance content and colony behavior of Escherichia coli, and the biofilm yield of csgD overexpressed strains increased by 79.35 % compared to that of the wild type strains (p < 0.05). In addition, the hydrophilicity of polyurethane fibres modified with potassium dichromate increased significantly, and biofilm adhesion increased by 105.80 %. Finally, the isoquercitrin yield in the catalytic reaction of the biofilm reinforced by the csgD overexpression strain and the modified carrier was 247.85 % higher than that of the untreated group. Overall, this study has developed engineered strains biofilm with special functions, providing possibilities for catalytic applications.


Assuntos
Proteínas de Escherichia coli , Proteínas de Escherichia coli/genética , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Regulação Bacteriana da Expressão Gênica , Biofilmes , Escherichia coli/genética , Proteínas de Bactérias/metabolismo
15.
Proc Natl Acad Sci U S A ; 121(14): e2321645121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38527201

RESUMO

Central Asia (CA) is one of the world's most significant arid regions, which is markedly impacted by global warming. A better understanding of the dynamical processes governing its Holocene climate variability is critical for a better understanding of possible future impacts of climate change in the region. To date, most of the existing CA paleoclimate records are from the summer precipitation-dominated eastern CA (ECA), with few records from the winter precipitation-dominated western CA (WCA). Here, we present a precisely dated (~6‰) and highly resolved (<4-y) record of hydroclimatic variations from the WCA covering the period between 7,774 and 656 y BP. Utilizing multiple proxies (δ18O, δ13C, and Sr/Ca) derived from a stalagmite from the Fergana Valley, Kyrgyzstan, we reveal a long-term drying trend in WCA, which is in contrast with the wetting trend in ECA. We propose that different responses of winter and summer westerly jets to seasonal solar insolation over the past 8,000 y may have resulted in an antiphased precipitation relationship between the WCA and ECA. Our data contain dominant quasiperiodicities of 1,400, 50 to 70, and 20 to 30 y, indicating close connections between the WCA climate and the North Atlantic. We further identified a series of droughts and pluvials on centennial-to-decadal timescales, which may have influenced regional societies and trans-Eurasian culture exchanges during historical and prehistorical times.

16.
PLoS One ; 19(3): e0299471, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451909

RESUMO

Structural planes decrease the strength and stability of rock masses, severely affecting their mechanical properties and deformation and failure characteristics. Therefore, investigation and analysis of structural planes are crucial tasks in mining rock mechanics. The drilling camera obtains image information of deep structural planes of rock masses through high-definition camera methods, providing important data sources for the analysis of deep structural planes of rock masses. This paper addresses the problems of high workload, low efficiency, high subjectivity, and poor accuracy brought about by manual processing based on current borehole image analysis and conducts an intelligent segmentation study of borehole image structural planes based on the U2-Net network. By collecting data from 20 different borehole images in different lithological regions, a dataset consisting of 1,013 borehole images with structural plane type, lithology, and color was established. Data augmentation methods such as image flipping, color jittering, blurring, and mixup were applied to expand the dataset to 12,421 images, meeting the requirements for deep network training data. Based on the PyTorch deep learning framework, the initial U2-Net network weights were set, the learning rate was set to 0.001, the training batch was 4, and the Adam optimizer adaptively adjusted the learning rate during the training process. A dedicated network model for segmenting structural planes was obtained, and the model achieved a maximum F-measure value of 0.749 when the confidence threshold was set to 0.7, with an accuracy rate of up to 0.85 within the range of recall rate greater than 0.5. Overall, the model has high accuracy for segmenting structural planes and very low mean absolute error, indicating good segmentation accuracy and certain generalization of the network. The research method in this paper can serve as a reference for the study of intelligent identification of structural planes in borehole images.


Assuntos
Rememoração Mental , Reconhecimento Psicológico , Comportamento Compulsivo , Generalização Psicológica , Processamento de Imagem Assistida por Computador
17.
Zootaxa ; 5406(2): 238-252, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38480154

RESUMO

Eupyrochroa Blair, 1914 is a small genus of fire-colored beetles (Coleoptera: Pyrochroidae) with two putative species recorded from limited historical distributions in China. The two species, E. insignita (Fairmaire, 1894) and E. limbaticollis (Pic, 1909), have been distinguished on the basis of color differences in the pronotum and scutellum, characters now known to exhibit significant variability. In the present study, adult morphology of the two species was compared, and partial fragments of cytochrome c oxidase subunit I (COI) from 36 samples representing 14 pyrochroid species were obtained by extraction and a GenBank search. Nucleotide composition, genetic distance, and phylogeny were analyzed. The results of morphological and molecular analyses indicate consistency, suggesting that the two species are indistinguishable by any significant measure. Therefore, Eupyrochroa limbaticollis (Pic, 1909) is proposed as a junior synonym of E. insignita (Fairmaire, 1894). The species is also redescribed and illustrated, including both adults and larvae.


Assuntos
Besouros , Animais , Filogenia , Larva , Bases de Dados de Ácidos Nucleicos
18.
Mar Drugs ; 22(2)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38393034

RESUMO

Six benzophenone derivatives, carneusones A-F (1-6), along with seven known compounds (7-13) were isolated from a strain of sponge-derived marine fungus Aspergillus carneus GXIMD00543. Their chemical structures were elucidated by detailed spectroscopic data and quantum chemical calculations. Compounds 5, 6, and 8 exhibited moderate anti-inflammatory activity on NO secretion using lipopolysaccharide (LPS)-induced RAW 264.7 cells with EC50 values of 34.6 ± 0.9, 20.2 ± 1.8, and 26.8 ± 1.7 µM, while 11 showed potent effect with an EC50 value of 2.9 ± 0.1 µM.


Assuntos
Anti-Inflamatórios , Aspergillus , Animais , Camundongos , Estrutura Molecular , Aspergillus/química , Anti-Inflamatórios/farmacologia , Células RAW 264.7
19.
iScience ; 27(2): 109008, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38352228

RESUMO

Disruption of circadian rhythms during fetal development may predispose mice to developing heart disease later in life. Here, we report that male, but not female, mice that had experienced chronic circadian disturbance (CCD) in utero were more susceptible to pathological cardiac remodeling compared with mice that had developed under normal intrauterine conditions. CCD-treated males showed ventricular chamber dilatation, enhanced myocardial fibrosis, decreased contractility, higher rates of induced tachyarrhythmia, and elevated expression of biomarkers for heart failure and myocardial remodeling. In utero CCD exposure also triggered sex-dependent changes in cardiac gene expression, including upregulation of the secretoglobin gene, Scgb1a1, in males. Importantly, cardiac overexpression of Scgb1a1 was sufficient to induce myocardial hypertrophy in otherwise naive male mice. Our findings reveal that in utero CCD exposure predisposes male mice to pathological remodeling of the heart later in life, likely as a consequence of SCGB1A1 upregulation.

20.
Nat Commun ; 15(1): 1728, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409095

RESUMO

A better understanding of the relative roles of internal climate variability and external contributions, from both natural (solar, volcanic) and anthropogenic greenhouse gas forcing, is important to better project future hydrologic changes. Changes in the evaporative demand play a central role in this context, particularly in tropical areas characterized by high precipitation seasonality, such as the tropical savannah and semi-desertic biomes. Here we present a set of geochemical proxies in speleothems from a well-ventilated cave located in central-eastern Brazil which shows that the evaporative demand is no longer being met by precipitation, leading to a hydrological deficit. A marked change in the hydrologic balance in central-eastern Brazil, caused by a severe warming trend, can be identified, starting in the 1970s. Our findings show that the current aridity has no analog over the last 720 years. A detection and attribution study indicates that this trend is mostly driven by anthropogenic forcing and cannot be explained by natural factors alone. These results reinforce the premise of a severe long-term drought in the subtropics of eastern South America that will likely be further exacerbated in the future given its apparent connection to increased greenhouse gas emissions.

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