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1.
Blood ; 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38958479

ABSTRACT

This study aimed to compare the efficacy and safety of eltrombopag plus diacerein vs. eltrombopag alone in patients with primary immune thrombocytopenia (ITP) who were previously unresponsive to 14 days of eltrombopag treatment at the full dose. Recruited patients were randomly assigned 1:1 to receive either eltrombopag plus diacerein (n=50) or eltrombopag monotherapy (n=52). Overall response rate, defined as a platelet count at or above 30×109/L, at least doubling of the baseline platelet count, and no bleeding, was reached in 44% of patients in the eltrombopag plus diacerein group compared with 13% in the eltrombopag group at day 15 (P = .0009), and reached in 42% of patients in the combination group compared with 12% in the monotherapy group at day 28 (P = .0006). The addition of diacerein to eltrombopag also led to a longer duration of response (P = .0004). The two most common treatment-emergent adverse events were respiratory infection and gastrointestinal reactions in the combination group, and fatigue and respiratory infection in the eltrombopag group. In conclusion, eltrombopag plus diacerein was well tolerated, and induced higher overall response rates and longer duration of response than eltrombopag alone, offering a rejuvenating salvage therapy for ITP patients unresponsive to 14 days of full dosage eltrombopag. Our work has the potential to enhance the care of patients treated with thrombopoietin receptor agonists, reducing the need for rapid transitions to less-preferable therapies. This study is registered at ClinicalTrials.gov as NCT04917679.

2.
Neuropsychiatr Dis Treat ; 20: 1309-1319, 2024.
Article in English | MEDLINE | ID: mdl-38933097

ABSTRACT

Purpose: The aim of our study was to explore the relation between serum levels of non-enzymatic antioxidants, thyroid function with the risk of non-suicidal self-injury (NSSI) in depressed adolescents. Patients and Methods: We retrospected the electronic records of 454 hospitalized patients aged 13-17 years old with a diagnosis of major depressive disorder (239 patients with NSSI and 215 subjects without NSSI), and collected their demographic and clinical information, including serum levels of total bilirubin (Tbil), uric acid (UA), free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH). Results: The incidence of NSSI was 52.6% among depressed adolescents aged 13-17, 57.1% in female and 38.5% in male. After using the propensity scoring method to exclude the influence of age between the two groups, it was found that patients with NSSI showed lower levels of Tbil (P=0.046) and UA (P=0.015) compared with those without NSSI. Logistic regression results showed that serum UA was associated with NSSI behavior in female patients (OR=0.995, 95% CI: 0.991-0.999, P=0.014), and TSH was associated with NSSI in male participants (OR=0.499, 95% CI: 0.267-0.932, P=0.029). Conclusion: Female and male may have different pathological mechanisms of NSSI. NSSI is more likely to be related to antioxidant reaction in female adolescent patients, while more likely to be related to thyroid function in male depressed adolescent patients.

3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(3): 819-824, 2024 Jun.
Article in Chinese | MEDLINE | ID: mdl-38926973

ABSTRACT

OBJECTIVE: To analyze the DTA (DNMT3A, TET2, ASXL1) mutations in patients with myeloproliferative neoplasms (MPN), and preliminarily explore their correlation with thromboembolism. METHODS: Clinical characteristics of 62 patients diagnosed de novo MPN at Central Hospital Affiliated to Shandong First Medical University from September 2016 to September 2022 were retrospectively analyzed. Next-generation sequencing was used to detect 35 MPN-related genes, and the DTA mutations in MPN patients and their relationship with thromboembolic events were analyzed. RESULTS: 75.8% (47/62) of the patients presented pathogenic non-driver mutations, and the mean number of pathogenic non-driver mutations per patient was 1.08. Among them, the most frequently mutated non-driver genes were TET2 (38.7%, 24/62), DNMT3A (9.7%, 6/62) and ASXL1 (6.5%, 4/62). The presence of DTA gene mutations was 50% (31/62) in the total MPN patients, and mainly accompanied by driver mutations. The mutation rate of DTA in patients aged ≥60 years was significantly higher than that in patients <60 years old (P =0.039). The incidence of thromboembolism in patients with DTA mutation was 58.1% (18/31), which was significantly higher than that in patients without DTA mutation (19.4%, 6/31) (P =0.002). The TET2 gene mutation rate in MPN patients with thromboembolism was 66.7% (16/24), which was significantly higher than that in patients without thromboembolism (21.1%, 8/38) (P =0.00). CONCLUSION: Patients with MPN have a higher incidence of DTA mutations, which are mainly accompanied by driver gene mutations. The incidence of thromboembolism in MPN patients with DTA mutations is higher than that in patients without DTA mutations. Especially, the elderly (≥60 years) essential thrombocythemia(ET) and polycythemia vera(PV) patients with TET2 mutation should be vigilant for thromboembolic events.


Subject(s)
DNA Methyltransferase 3A , DNA-Binding Proteins , Dioxygenases , Mutation , Myeloproliferative Disorders , Proto-Oncogene Proteins , Repressor Proteins , Thromboembolism , Humans , Middle Aged , Myeloproliferative Disorders/genetics , Myeloproliferative Disorders/complications , Thromboembolism/genetics , Retrospective Studies , Proto-Oncogene Proteins/genetics , DNA-Binding Proteins/genetics , Repressor Proteins/genetics , DNA (Cytosine-5-)-Methyltransferases/genetics , Male , Female , High-Throughput Nucleotide Sequencing
4.
Polymers (Basel) ; 16(12)2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38931964

ABSTRACT

The development of micro cracks in shale formations can easily lead to wellbore instability caused by liquid phase invasion. In order to effectively seal the shale micropores, the surface treatment of nano-SiO2 particles was developed using the silicane coupling agent A-1891. Then, the temperature-sensitive polypenic acrylamide polymer was modified onto the surface of the nanoprocal particle through reaction to obtain the nanosomal blocking agent ASN. The infrared spectrum shows that there are chemical bonds between the generated polymer chains, rather than simple physical composites, indicating the successful synthesis of the temperature-responsive nanosealing agent ASN. The particle size analysis showed that the synthesized nanoparticles in ASN have a uniform particle size distribution and display no agglomeration phenomenon. Applying ASN as a sealing agent in drilling fluid effectively fills the nanoscale micropores and microcracks in shale, making shale denser and significantly improving the wellbore stability of shale formations. In addition, it has good temperature resistance, can adapt to reservoirs at different temperatures, is non-toxic and environmentally friendly, and has good prospects for stable applications in shale formation wellbore.

5.
Cell Death Differ ; 31(6): 738-752, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38594444

ABSTRACT

Glioblastoma (GBM) is the most aggressive malignant primary brain tumor characterized by a highly heterogeneous and immunosuppressive tumor microenvironment (TME). The symbiotic interactions between glioblastoma stem cells (GSCs) and tumor-associated macrophages (TAM) in the TME are critical for tumor progression. Here, we identified that IFI35, a transcriptional regulatory factor, plays both cell-intrinsic and cell-extrinsic roles in maintaining GSCs and the immunosuppressive TME. IFI35 induced non-canonical NF-kB signaling through proteasomal processing of p105 to the DNA-binding transcription factor p50, which heterodimerizes with RELB (RELB/p50), and activated cell chemotaxis in a cell-autonomous manner. Further, IFI35 induced recruitment and maintenance of M2-like TAMs in TME in a paracrine manner. Targeting IFI35 effectively suppressed in vivo tumor growth and prolonged survival of orthotopic xenograft-bearing mice. Collectively, these findings reveal the tumor-promoting functions of IFI35 and suggest that targeting IFI35 or its downstream effectors may provide effective approaches to improve GBM treatment.


Subject(s)
Glioblastoma , NF-kappa B , Neoplastic Stem Cells , Signal Transduction , Tumor-Associated Macrophages , Glioblastoma/metabolism , Glioblastoma/pathology , Glioblastoma/genetics , Humans , Animals , Mice , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Tumor-Associated Macrophages/metabolism , Tumor-Associated Macrophages/pathology , NF-kappa B/metabolism , Brain Neoplasms/pathology , Brain Neoplasms/metabolism , Brain Neoplasms/genetics , Cell Line, Tumor , Tumor Microenvironment
6.
Opt Express ; 32(7): 10910-10924, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38570953

ABSTRACT

Thin-film polarizing beam splitters (PBSs) fulfill a pivotal role in laser beam splitting, modulation, shaping and isolation. In this study, a high-reliability infrared broadband thin-film PBS was developed. To correct for tensile stress in Ge/YbF3 multilayer coatings, ZnSe compensation layers were incorporated in the multilayer design. The effects of different symmetrical periods on the spectral properties of the infrared PBS were systematically discussed. The infrared PBS operated at 45° and in the long-wave infrared (LWIR) band. Using the percent of optical extrema monitoring (POEM) strategy combined with the high-temperature optical constants (HTOC) of Ge film, the infrared PBS was precisely fabricated on ZnSe substrates. Subsequently, the spectral performance and film reliability of the infrared PBS were carefully characterized. Specifically, the transmittance of p-polarization surpassed 96%, while the extinction ratio exceeded 100:1 within the 10.6 ± 0.15 µm band. The infrared PBS demonstrated commendable environmental reliability, in addition to exhibiting excellent spectral characteristics.

7.
Haematologica ; 109(7): 2165-2176, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38235512

ABSTRACT

Sovleplenib (HMPL-523) is a selective spleen tyrosine kinase (Syk) inhibitor with anti-tumor activity in preclinical models of B-cell malignancy. We conducted a dose-escalation and dose-expansion phase I study of sovleplenib in patients with relapsed/ refractory mature B-cell tumors. Dose escalation followed a 3+3 design; patients received oral sovleplenib (200-800 mg once daily [q.d.] or 200 mg twice daily [b.i.d.], 28-day cycles). During dose expansion, patients were enrolled into four cohorts per lymphoma classification and treated at the recommended phase II dose (RP2D) (clinicaltrials gov. Identifier: NCT02857998). Overall, 134 Chinese patients were enrolled (dose escalation, N=27; dose expansion, N=107). Five patients experienced dose-limiting toxicities: one each of amylase increased (200 mg q.d.), febrile neutropenia (800 mg q.d.), renal failure (800 mg q.d.), hyperuricemia and blood creatine phosphokinase increased (200 mg b.i.d.) and blood bilirubin increased and pneumonia (200 mg b.i.d.). RP2D was determined as 600 mg (>65 kg) or 400 mg (≤65 kg) q.d.. The primary efficacy end point of independent review committee-assessed objective response rate in indolent B-cell lymphoma was 50.8% (95% confidence interval: 37.5- 64.1) in 59 evaluable patients at RP2D (follicular lymphoma: 60.5%, marginal zone lymphoma: 28.6%, lymphoplasmacytic lymphoma/Waldenström macroglobulinemia, 0%). The most common (≥10% patients) grade ≥3 treatment-related adverse events in the dose-expansion phase were decreased neutrophil count (29.9%), pneumonia (12.1%) and decreased white blood cell count (11.2%). Pharmacokinetic exposures increased dose-proportionally with ascending dose levels from 200-800 mg, without observed saturation. Sovleplenib showed anti-tumor activity in relapsed/refractory B-cell lymphoma with acceptable safety. Further studies are warranted.


Subject(s)
Lymphoma, B-Cell , Protein Kinase Inhibitors , Syk Kinase , Humans , Middle Aged , Male , Female , Syk Kinase/antagonists & inhibitors , Aged , Adult , Lymphoma, B-Cell/drug therapy , Lymphoma, B-Cell/pathology , Protein Kinase Inhibitors/therapeutic use , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/pharmacokinetics , Protein Kinase Inhibitors/adverse effects , Young Adult , Aged, 80 and over , Treatment Outcome , Drug Resistance, Neoplasm/drug effects , Maximum Tolerated Dose , Pyrazines/administration & dosage , Pyrazines/therapeutic use , Pyrazines/pharmacokinetics , Pyrazines/adverse effects , Recurrence , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Indazoles , Morpholines
9.
RSC Adv ; 13(33): 23169-23180, 2023 Jul 26.
Article in English | MEDLINE | ID: mdl-37533778

ABSTRACT

Graphene is a material formed with carbon atoms connected by sp2 hybridization. It is extremely strong and very ductile, and is superhydrophobic and superlipophilic. It has important application prospects in materials science, micro and nano processing, energy, aerospace and biomedicine. Graphene also has some applications in the petroleum industry. As nanoscale materials, graphene-based materials can plug nano-pores and prevent water intrusion into clay minerals during the drilling process, they are suitable for sliding between layers and can be used as lubricants due to the two-dimensional structure. The adsorption properties of graphene-based materials allow them to improve the treatment rate when treating oily wastewater. This paper compiles recent advances in the application of graphene and its derivatives in oilfield extraction, including improving drilling fluid performance, enhanced oil recovery and oily wastewater treatment. We compare the performance advantages of graphene-based materials over other additives, and summarize the mechanism of action of graphene-based materials. The shortcomings of current research are identified and future research and improvement directions are envisaged.

10.
Clin Cancer Res ; 29(18): 3779-3792, 2023 09 15.
Article in English | MEDLINE | ID: mdl-37439870

ABSTRACT

PURPOSE: The dynamic interplay between glioblastoma stem cells (GSC) and tumor-associated macrophages (TAM) sculpts the tumor immune microenvironment (TIME) and promotes malignant progression of glioblastoma (GBM). However, the mechanisms underlying this interaction are still incompletely understood. Here, we investigate the role of CXCL8 in the maintenance of the mesenchymal state of GSC populations and reprogramming the TIME to an immunosuppressive state. EXPERIMENTAL DESIGN: We performed an integrative multi-omics analyses of RNA sequencing, GBM mRNA expression datasets, immune signatures, and epigenetic profiling to define the specific genes expressed in the mesenchymal GSC subsets. We then used patient-derived GSCs and a xenograft murine model to investigate the mechanisms of tumor-intrinsic and extrinsic factor to maintain the mesenchymal state of GSCs and induce TAM polarization. RESULTS: We identified that CXCL8 was preferentially expressed and secreted by mesenchymal GSCs and activated PI3K/AKT and NF-κB signaling to maintain GSC proliferation, survival, and self-renewal through a cell-intrinsic mechanism. CXCL8 induced signaling through a CXCR2-JAK2/STAT3 axis in TAMs, which supported an M2-like TAM phenotype through a paracrine, cell-extrinsic pathway. Genetic- and small molecule-based inhibition of these dual complementary signaling cascades in GSCs and TAMs suppressed GBM tumor growth and prolonged survival of orthotopic xenograft-bearing mice. CONCLUSIONS: CXCL8 plays critical roles in maintaining the mesenchymal state of GSCs and M2-like TAM polarization in GBM, highlighting an interplay between cell-autonomous and cell-extrinsic mechanisms. Targeting CXCL8 and its downstream effectors may effectively improve GBM treatment.


Subject(s)
Brain Neoplasms , Glioblastoma , Humans , Animals , Mice , Glioblastoma/pathology , Tumor-Associated Macrophages/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Brain Neoplasms/pathology , Cell Line, Tumor , Neoplastic Stem Cells/metabolism , Cell Proliferation , Tumor Microenvironment/genetics
11.
Neuro Oncol ; 25(9): 1578-1591, 2023 09 05.
Article in English | MEDLINE | ID: mdl-36934350

ABSTRACT

BACKGROUND: Glioblastomas (GBMs) display striking dysregulation of metabolism to promote tumor growth. Glioblastoma stem cells (GSCs) adapt to regions of heterogeneous nutrient availability, yet display dependency on de novo cholesterol biosynthesis. The transcription factor Sterol Regulatory Element-Binding Protein 2 (SREBP2) regulates cholesterol biosynthesis enzymes and uptake receptors. Here, we investigate adaptive behavior of GSCs under different cholesterol supplies. METHODS: In silico analysis of patient tumors demonstrated enrichment of cholesterol synthesis associated with decreased angiogenesis. Comparative gene expression of cholesterol biosynthesis enzymes in paired GBM specimens and GSCs were performed. In vitro and in vivo loss-of-function genetic and pharmacologic assays were conducted to evaluate the effect of SREBP2 on GBM cholesterol biosynthesis, proliferation, and self-renewal. Chromatin immunoprecipitation quantitative real-time PCR was leveraged to map the regulation of SREBP2 to cholesterol biosynthesis enzymes and uptake receptors in GSCs. RESULTS: Cholesterol biosynthetic enzymes were expressed at higher levels in GBM tumor cores than in invasive margins. SREBP2 promoted cholesterol biosynthesis in GSCs, especially under starvation, as well as proliferation, self-renewal, and tumor growth. SREBP2 governed the balance between cholesterol biosynthesis and uptake in different nutrient conditions. CONCLUSIONS: SREBP2 displays context-specific regulation of cholesterol biology based on its availability in the microenvironment with induction of cholesterol biosynthesis in the tumor core and uptake in the margin, informing a novel treatment strategy for GBM.


Subject(s)
Glioblastoma , Humans , Cell Line, Tumor , Cholesterol/metabolism , Gene Expression Regulation , Glioblastoma/pathology , Neoplastic Stem Cells/metabolism , Stem Cells/metabolism , Stem Cells/pathology , Sterol Regulatory Element Binding Protein 2/genetics , Sterol Regulatory Element Binding Protein 2/metabolism , Tumor Microenvironment
12.
ACS Omega ; 8(10): 9291-9297, 2023 Mar 14.
Article in English | MEDLINE | ID: mdl-36936280

ABSTRACT

Nanosealing technology has become the key to overcoming the wellbore instability problem in deep and ultradeep shale formations. In this Article, the terpolymer poly(MM-EM-BM) was synthesized from methyl methacrylate, ethyl methacrylate, and butyl methacrylate by a Michael addition reaction. The poly(MM-EM-BM) nanoparticles were investigated by Fourier transform infrared spectroscopy, laser scattering analysis, and thermogravimetric analysis. The results imply that the particle size range of poly(MM-EM-BM) is between 33.90 and 135.62 nm and the average diameter is about 85.95 nm at room temperature, which can maintain excellent stability at 382.75 °C. The effects of poly(MM-EM-BM) on the properties of oil-based drilling fluids (OBDFs) were ascertained through experiments on the rheological performance, electrical stability, and high-temperature and high-pressure (HTHP) filtration loss. The results suggested that when the amount of added poly(MM-EM-BM) increases, the apparent viscosity, plastic viscosity, dynamic shear force, and demulsification voltage of the drilling fluids will increase correspondingly; in contrast, the HTHP filtration loss gradually decreased. When poly(MM-EM-BM) is added at 0.75%, the kinetic-to-plastic ratio of the drilling fluids is 0.24 and the filtration loss is 0.6 mL, showing excellent overall performance. The drilling fluids have a good rock-carrying ability and water loss wall-building property. The sealing performance and mechanism of poly(MM-EM-BM) were researched by the method of a sealing performance test under high temperature. The results indicated that the more poly(MM-EM-BM) used, the higher the sealing efficiency of the mud cake and the core as the sealing medium. When poly(MM-EM-BM) was added at 0.75%, the sealing rates of the mud cake and the core as the sealing medium reached the maximum sealing rates of 40.30% and 91.48%, respectively. When poly(MM-EM-BM) enters the core nanopore joint for a certain distance under formation pressure, a tight sealing layer will be formed to effectively prevent the entry of filtrate. Poly(MM-EM-BM) as a potential oil-based nanosealing agent is expected to solve the problem caused by wellbore instability in shale horizontal wells.

13.
J Econ Entomol ; 116(2): 574-583, 2023 04 24.
Article in English | MEDLINE | ID: mdl-36757382

ABSTRACT

The black cutworm, Agrotis ipsilon (Hufnagel), a seasonal migrant and a prolific generalist, can feed on nearly all vegetables and grain crops, causing considerable economic impacts on a global scale. Given its cryptic nature, A. ipsilon management has been extremely challenging. Chitin synthase (CHS), a key enzyme involved in chitin biosynthetic pathway and crucially important for the growth and development of insects, is the molecular target of chitin synthesis inhibitors, a group of broad-spectrum insecticides that is compatible with Integrated Pest Management practices. In this study, we investigated the potential of targeting chitin synthases to control A. ipsilon. As a result, two chitin synthases, AiCHS1 and AiCHS2, were identified and cloned from A. ipsilon. The temporal-spatial distribution study showed that AiCHS1 was predominantly expressed at the pupal stage and most abundant among tissues of head capsule and integument, while AiCHS2 was mainly expressed at the sixth instar larval stage and tissues of foregut and midgut. RNAi-based functional study confirmed gene silencing caused significant reduction in the expression levels of the corresponding mRNA, as well as resulted in abnormal pupation and mortality, respectively. Furthermore, under the treatment of lufenuron, a chitin synthesis inhibitor, A. ipsilon responded with an elevated expression in AiCHS1 and AiCHS2, while larvae showed difficulty in shedding old cuticle, and a cumulative mortality of 69.24% at 48 h. In summary, chitin synthases are crucial for chitin biosynthesis in A. ipsilon and can be targeted for the control (e.g., RNAi-based biopesticides) of this devastating insect pest.


Subject(s)
Insecticides , Lepidoptera , Moths , Animals , Chitin Synthase , Larva , Pest Control, Biological/methods , Chitin
14.
Biology (Basel) ; 11(12)2022 Dec 07.
Article in English | MEDLINE | ID: mdl-36552286

ABSTRACT

The success of the degradation of the extraembryonic serosal cuticle and the second embryonic cuticle (pro-nymphal cuticle) is essential for the development and molting of nymph from egg in Orthoptera Locusta migratoria. Chitinase 5 is an important gene for chitin degradation in nymphs and in the egg stage. In this study, we investigated the important roles of chitinase 5-1 (LmCht5-1) and chitinase 5-2 (LmCht5-2) in the degradation of the serosal and pro-nymphal cuticles during locust embryonic development. The serosal cuticle degrades from 7-day-old embryos (E7) to E13, along with the degradation of the pro-nymphal cuticle, which begins at E12 to E14. The mRNA and protein of LmCht5-1 and LmCht5-2 are expressed during the degradation process of the serosal cuticle and the pro-nymphal cuticle. RNAi experiments at the embryonic stage show that both dsLmCht5-1 and dsLmCht5-2 contribute to the failure of development in early and late embryogenesis. Further, during the serosal cuticle molting process, ultra-structure analysis indicated that dsLmCht5-1 prevented the loss of the coarse chitin layer in the upper part in both early and late embryogenesis. Meanwhile, dsLmCht5-2 blocked the degradation of the lower fine chitin layer at the early stage and blocked the chitin degradation of loose coarse chitin in the late molting process. During the degradation of the pro-nymphal cuticle, dsLmCht5-1 suppresses chitin degradation between layers in the procuticle, while dsLmCht5-2 suppresses chitin degradation into filaments inside of the layer. In summary, our results suggest that both LmCht5-1 and LmCht5-2 contribute to the degradation of the serosal and pro-nymphal cuticles during the locust embryonic stage.

15.
RSC Adv ; 12(47): 30328-30334, 2022 Oct 24.
Article in English | MEDLINE | ID: mdl-36337958

ABSTRACT

For wellbore stability in shale formations, the development of environmentally friendly and efficient shale inhibitors is urgently needed. Herein, we report the preparation of choline chloride-modified graphene (Ch-G). The inhibition and interaction mechanisms of choline chloride-modified graphene on montmorillonite were also investigated. We evaluated the inhibition of Ch-G via linear swelling and rolling recovery and selected the inorganic salt inhibitor KCl as the control group. The lowest swelling height of 2.10 mm and the highest rolling recovery of 78.87% were achieved, indicating the excellent inhibition performance of Ch-G. The mechanism of inhibition of Ch-G was determined by Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy, and atomic force microscopy. The Ch-G formed hydrogen bonds, coordination, and electrostatic interactions with the surface of montmorillonite and entered the montmorillonite via intercalation to achieve the inhibition. The increase in the nitrogen atom content in Ch-G led to the production of more positive ions and the formation of more ion bands, which enhanced the ability to inhibit shale hydration. The addition of Ch-G produced larger montmorillonite sheets, demonstrating its effective inhibition ability, which is needed to enable drilling fluids to stably drill into shale formations.

16.
ACS Omega ; 7(45): 40799-40806, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36406505

ABSTRACT

Well wall instability is one of the problems that seriously affect the efficiency of oil and gas drilling and extraction, and the economic losses caused by accidents due to well wall instability amount to billions of dollars every year. Aiming at the fact that well wall stabilization is the current technical difficulty of drilling shale gas horizontal wells with oil-based drilling fluids, the oil-based nanoplugging agent poly(MMA-BMA-BA-St) was synthesized by the Michael addition reaction with compounds such as styrene, methyl methacrylate, and butyl methacrylate as raw materials. The structure and characteristics of the oil-based nanoblocker poly(MMA-BMA-BA-St) were characterized by infrared spectroscopy, particle size analysis, and thermal weight loss analysis. The particle size distribution of poly(MMA-BMA-BA-St) is 80.56-206.61 nm, with an average particle size of 137.10 nm, and it can resist the high temperature of 372 °C. The effects of poly(MMA-BMA-BA-St) on the performance parameters of oil-based drilling fluids were investigated by rheological experiments, electrical stability tests, and HTHP filtration loss experiments. The results show that when poly(MMA-BMA-BA-St) is added at 0.5 wt %, it has less influence on the rheological parameters of drilling fluids, the breaking emulsion pressure remains basically unchanged, the stability of the drilling fluid is better, the dynamic-plastic ratio of the drilling fluid is higher than 0.27, the filtration loss is the lowest, and it shows good rock-carrying properties. The results of mud cake experiments and artificial lithology experiments show that poly(MMA-BMA-BA-St) has the best sealing effect, with a mud cake permeability of 1.12 × 10-4 mD and a sealing rate of 30.00% when added at 0.5 wt %; the artificial core permeability was 4.0 × 10-4 mD, and the sealing rate was 91.23%. Poly(MMA-BMA-BA-St) showed good sealing performance. The oil-based nanoplugging agent poly(MMA-BMA-BA-St) has good dispersion in oil-based drilling fluids and can enter the nanopore joints to form a dense plugging layer under the action of formation pressure to prevent the intrusion of drilling fluids, thus reducing the impact of drilling fluids on the formation, maintaining the stability of the well wall and reducing downhole complications.

17.
Sci Rep ; 12(1): 17263, 2022 10 14.
Article in English | MEDLINE | ID: mdl-36241660

ABSTRACT

The devastating Varroa mite (Varroa destructor Anderson and Trueman) is an obligatory ectoparasite of the honey bee, contributing to significant colony losses in North America and throughout the world. The limited number of conventional acaricides to reduce Varroa mites and prevent disease in honey bee colonies is challenged with wide-spread resistance and low target-site selectivity. Here, we propose a biorational approach using comparative genomics for the development of honey bee-safe and selective acaricides targeting the Varroa mite-specific neuropeptidergic system regulated by proctolin, which is lacking in the honey bee. Proctolin is a highly conserved pentapeptide RYLPT (Arg-Tyr-Leu-Pro-Thr) known to act through a G protein-coupled receptor to elicit myotropic activity in arthropod species. A total of 33 different peptidomimetic and peptide variants were tested on the Varroa mite proctolin receptor. Ligand docking model and mutagenesis studies revealed the importance of the core aromatic residue Tyr2 in the proctolin ligand. Peptidomimetics were observed to have significant oral toxicity leading to the paralysis and death of Varroa mites, while there were no negative effects observed for honey bees. We have demonstrated that a taxon-specific physiological target identified by advanced genomics information offers an opportunity to develop Varroa mite-selective acaricides, hence, expedited translational processes.


Subject(s)
Acaricides , Peptidomimetics , Varroidae , Acaricides/pharmacology , Animals , Bees/genetics , Genomics , Ligands , Peptidomimetics/pharmacology , Varroidae/physiology
18.
RSC Adv ; 12(35): 22853-22868, 2022 Aug 10.
Article in English | MEDLINE | ID: mdl-36105991

ABSTRACT

The problem of high friction and high torque is one of the most troublesome problems for engineers in extended reach wells and long horizontal wells. Generally, the friction coefficient of oil-based drilling fluid is around 0.08, while the friction coefficient of water-based drilling fluid exceeds 0.2, which is much higher than that of oil-based drilling fluid. With the increasingly stringent environmental regulations, water-based drilling fluids have gradually become a better choice than oil-based drilling fluids. Therefore, lubricants become a key treatment agent for reducing the friction coefficient of water-based drilling fluids. Although there have been many related studies, there is a lack of comprehensive reviews on environmentally friendly water-based drilling fluid lubricants. In general, water-based drilling fluid lubricants can be mainly divided into solid lubricants, ester-based lubricants, alcohol-based lubricants, and nano-based lubricants. Vegetable oil ester-based lubricants, biodiesel lubricants, and dispersible nano-lubricants are all promising environmentally friendly water-based drilling fluid lubricants. Understanding the lubrication mechanism of different types of lubricants and clarifying the evaluation methods of lubricants is an important prerequisite for the next development in high-performance water-based drilling fluid lubricants. Therefore, the purpose of this paper is to give a comprehensive overview of water-based drilling fluid lubricants in recent years, in order to fully understand the development and lubrication mechanism of water-based drilling fluid lubricants, and provide new ideas for subsequent research on water-based drilling fluid lubricants.

19.
Neuropsychiatr Dis Treat ; 18: 1469-1477, 2022.
Article in English | MEDLINE | ID: mdl-35899094

ABSTRACT

Purpose: Uric acid (UA) is thought to exert neuroprotective roles. The purpose of this study was to examine the association of serum UA with suicide attempts (SA) in adolescents and young adults with major depressive disorder (MDD). Patients and Methods: We retrospectively recruited 533 participants with MDD aged 13 to 25 years, of which 168 had a history of SA in the past three months and 365 did not have a history of SA. Serum UA levels were measured using the uricase-peroxidase coupling method. In addition to overall serum UA level comparison in MDD individuals with and without SA, a stratified analysis by biological sex was carried out. Results: Compared to MDD individuals without a history of SA, serum UA levels were significantly lower in MDD individuals with SA (P < 0.001). Female MDD, but not male MDD individuals, with SA exhibited lower levels of UA than those without SA (P < 0.01). Importantly, serum UA remained significantly associated with SA in MDD individuals (OR = 0.996, 95% CI: 0.993~0.999, P < 0.01) when controlling for possible confounding variables. Conclusion: This research identifies a relationship between serum UA levels and SA in adolescents and young adults with MDD. UA may represent a biological risk marker for SA, in particular for female MDD individuals.

20.
Cancer Res ; 82(18): 3321-3334, 2022 09 16.
Article in English | MEDLINE | ID: mdl-35841593

ABSTRACT

Glioblastoma (GBM) is a complex ecosystem that includes a heterogeneous tumor population and the tumor-immune microenvironment (TIME), prominently containing tumor-associated macrophages (TAM) and microglia. Here, we demonstrated that ß2-microglobulin (B2M), a subunit of the class I major histocompatibility complex (MHC-I), promotes the maintenance of stem-like neoplastic populations and reprograms the TIME to an anti-inflammatory, tumor-promoting state. B2M activated PI3K/AKT/mTOR signaling by interacting with PIP5K1A in GBM stem cells (GSC) and promoting MYC-induced secretion of transforming growth factor-ß1 (TGFß1). Inhibition of B2M attenuated GSC survival, self-renewal, and tumor growth. B2M-induced TGFß1 secretion activated paracrine SMAD and PI3K/AKT signaling in TAMs and promoted an M2-like macrophage phenotype. These findings reveal tumor-promoting functions of B2M and suggest that targeting B2M or its downstream axis may provide an effective approach for treating GBM. SIGNIFICANCE: ß2-microglobulin signaling in glioblastoma cells activates a PI3K/AKT/MYC/TGFß1 axis that maintains stem cells and induces M2-like macrophage polarization, highlighting potential therapeutic strategies for targeting tumor cells and the immunosuppressive microenvironment in glioblastoma.


Subject(s)
Brain Neoplasms , Glioblastoma , Tumor Microenvironment , beta 2-Microglobulin/metabolism , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Line, Tumor , Ecosystem , Glioblastoma/metabolism , Glioblastoma/pathology , Humans , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Stem Cells/pathology , TOR Serine-Threonine Kinases , Transforming Growth Factor beta1 , Tumor-Associated Macrophages
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