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1.
bioRxiv ; 2024 Aug 29.
Article de Anglais | MEDLINE | ID: mdl-39372766

RÉSUMÉ

There has been renewed interest in neural transplantation of cells and tissues for brain repair. Recent studies have demonstrated the ability of transplanted neural precursor cells and in vitro grown organoids to mature and locally integrate into host brain neural circuitry. Much effort has focused on how the transplant behaves and functions after the procedure, but the extent to which the host brain can properly innervate the transplant, particularly in the context of aging, is largely unexplored. Here we report that transplantation of rat embryonic cortical precursor cells into the cerebrospinal fluid-subventricular zone (CSF-SVZ) of adult rat brains generates a brain-like tissue (BLT) at an ectopic site. This model allows for the assessment of long-range connectivity and cellular interactions between the transplant and the host brain as a function of host age. The transplanted precursor cells initially proliferate, then differentiate, and develop into mature BLTs, which receive supportive cellular components from the host including blood vessels, microglia, astrocytes, and oligodendrocytes. There was integration of the BLT into the host brain which occurred at all ages studied, suggesting that host age does not affect the maturation and integration of the transplant-derived BLT. Long-range axonal projections from the BLT into the host brain were robust throughout the different aged recipients. However, long-distance innervation originating from the host brain into the BLT significantly declined with age. This work demonstrates the feasibility and utility of integrating new neural tissue structures at ectopic sites into adult brain circuits to study host-transplant interactions.

2.
J Hazard Mater ; 479: 135703, 2024 Nov 05.
Article de Anglais | MEDLINE | ID: mdl-39226685

RÉSUMÉ

Cadmium (Cd) represents a hazardous heavy metal, prevalent in agricultural soil due to industrial and agricultural expansion. Its propensity for being absorbed by edible plants, even at minimal concentrations, and subsequently transferred along the food chain poses significant risks to human health. Accordingly, it is imperative to investigate novel genes and mechanisms that govern Cd tolerance and detoxification in plants. Here, we discovered that the transcription factor MYC2 directly binds to the promoters of HMA2 and HMA4 to repress their expression, thereby altering the distribution of Cd in plant tissues and negatively regulating Cd stress tolerance. Additionally, molecular, biochemical, and genetic analyses revealed that MYC2 interacts and cooperates with MYB43 to negatively regulate the expression of HMA2 and HMA4 and Cd stress tolerance. Notably, under Cd stress conditions, MYC2 undergoes degradation, thereby alleviating its inhibitory effect on HMA2 and HMA4 expression and plant tolerance to Cd stress. Thus, our study highlights the dynamic regulatory role of MYC2, in concert with MYB43, in regulating the expression of HMA2 and HMA4 under both normal and Cd stress conditions. These findings present MYC2 as a promising target for directed breeding efforts aimed at mitigating Cd accumulation in edible plant roots.


Sujet(s)
Protéines d'Arabidopsis , Arabidopsis , Cadmium , Régulation de l'expression des gènes végétaux , Facteurs de transcription , Cadmium/toxicité , Cadmium/métabolisme , Arabidopsis/génétique , Arabidopsis/métabolisme , Arabidopsis/effets des médicaments et des substances chimiques , Facteurs de transcription/métabolisme , Facteurs de transcription/génétique , Régulation de l'expression des gènes végétaux/effets des médicaments et des substances chimiques , Protéines d'Arabidopsis/génétique , Protéines d'Arabidopsis/métabolisme , Stress physiologique , Facteurs de transcription à motifs basiques hélice-boucle-hélice et à glissière à leucines/métabolisme , Facteurs de transcription à motifs basiques hélice-boucle-hélice et à glissière à leucines/génétique , Régions promotrices (génétique) , Végétaux génétiquement modifiés/métabolisme , Végétaux génétiquement modifiés/génétique
3.
Thorac Cancer ; 2024 Sep 14.
Article de Anglais | MEDLINE | ID: mdl-39275876

RÉSUMÉ

Radiotherapy is a crucial component in the holistic management of breast cancer, with approximately 60% of individuals diagnosed with breast cancer requiring this treatment. As the survival rate of individuals with breast cancer has significantly increased, there is a growing focus on the long-term well-being of patients. Proton therapy (PT) is a new and rapidly developing radiotherapy method. In comparison with conventional photon therapy, PT offers the benefits of decreased radiation toxicity and increased dosage in the designated region. This can extend patients' lifespan and enhance their overall well-being. The present analysis examines the function of PT in diminishing the harmful effects of radiation in cases of breast cancer, while also providing a brief overview of the future potential and obstacles associated with PT for breast cancer.

4.
ACS Omega ; 9(35): 36993-37001, 2024 Sep 03.
Article de Anglais | MEDLINE | ID: mdl-39246462

RÉSUMÉ

Unlike conventional natural gas reservoirs, shale gas development involves systematic changes in methane carbon isotopes that cannot be effectively described by existing isotope fractionation models and mechanisms. Therefore, based on fundamental theories such as Rayleigh fractionation, mass transfer flow, and mass conservation, this study established isotopic fractionation equations for methane in adsorbed and free gas. By considering adsorbed and free gases as two end-members and using an isotope mixing model, a fractionation model for methane carbon isotopes during shale gas desorption was constructed. This model quantifies the isotopic fractionation effects during shale gas desorption and elucidates the mechanism of methane carbon isotope fractionation. Using on-site desorbed gas content and isotope data, parameter fitting and model calculations were conducted to characterize methane carbon isotope variations throughout the process of shale core field desorption. The results show a pattern of "initially negative and then turning positive," consistent with those of physical simulation experiments. It was clarified that differences in mixing the two end-members and isotopic fractionation play key roles in the variation of methane carbon isotopic composition in shale gas. By applying the methane carbon isotope fractionation model, the contribution of adsorbed gas during shale gas production was explored. It was found that in the early stage of development, the adsorbed gas in Well JY 1 was negligible. After nearly seven years of development, the contribution of adsorbed gas in the later stage has only reached nearly 15%, indicating that the production contribution of adsorbed gas is still less than 0.3 million cubic feet per day. The open flow of Well JY 6-2 is more conducive to the production of adsorbed gas, but the production capacity is still mainly contributed by free gas, indicating that the shale gas production capacity in the later stage in the Jiaoshiba gas field is still primarily dominated by free gas.

5.
ACS Appl Mater Interfaces ; 16(36): 47797-47807, 2024 Sep 11.
Article de Anglais | MEDLINE | ID: mdl-39188207

RÉSUMÉ

For solving the trade-off relationship of the polarization and breakdown electric field, ferroelectric films with high polarization are playing a critical role in energy storage capacitor applications, especially at moderate/low electric fields. In this work, we propose a multiscale structure (including defect, domain, and grain structures) synergetic optimization strategy to optimize the polarization behavior and energy storage performances of BiMg0.5Ti0.5O3 (BMT) ferroelectric films by introducing Sr0.7La0.2TiO3 (SLT) without compromising the breakdown strength. At a moderate electric field of 2917 kV/cm, a high discharge density of 72.2 J/cm3 has been achieved in 0.9BMT-0.1SLT films, together with good frequency, thermal, and cycle stabilities for energy storage. Importantly, the phase difference Δφ is utilized to quantitatively evaluate the polarization switching mobility of the ferroelectric domain/PNRs at an external electric field stimulation. This research demonstrates that a multiscale structure optimization strategy could effectively regulate the energy storage performance, and ecofriendly BMT-based materials are promising candidates for next-generation energy storage capacitors, especially at moderate/low electric fields.

6.
J Hazard Mater ; 477: 135313, 2024 Sep 15.
Article de Anglais | MEDLINE | ID: mdl-39067296

RÉSUMÉ

Industrial and agricultural production processes lead to the accumulation of cadmium (Cd) in soil, resulting in crops absorb Cd from contaminated soil and then transfer it to human body through the food chain, posing a serious threat to human health. Thus, it is necessary to explore novel genes and mechanisms involved in regulating Cd tolerance and detoxification in plants. Here, we found that CDR1, a DUF946 domain containing protein, localizes to the plasma membrane and positively regulates Cd stress tolerance. The cdr1 mutants exhibited Cd sensitivity, accumulated excessive Cd in the seeds and roots, but decreased in leaves. However, CDR1-OE transgenic plants not only showed Cd tolerance but also significantly reduced Cd in seeds and roots. Additionally, both in vitro and in vivo assays demonstrated an interaction between CDR1 and OPT3. Cell free protein degradation and OPT3 protein level determination assays indicated that CDR1 could maintain the stability of OPT3 protein. Moreover, genetic phenotype analysis and Cd content determination showed that CDR1 regulates Cd stress tolerance and affect the distribution of Cd in plants by maintaining the stability of OPT3 protein. Our discoveries provide a key candidate gene for directional breeding to reduce Cd accumulation in edible seeds of crops.


Sujet(s)
Protéines d'Arabidopsis , Arabidopsis , Cadmium , Végétaux génétiquement modifiés , Arabidopsis/génétique , Arabidopsis/effets des médicaments et des substances chimiques , Arabidopsis/métabolisme , Cadmium/toxicité , Cadmium/métabolisme , Protéines d'Arabidopsis/génétique , Protéines d'Arabidopsis/métabolisme , Végétaux génétiquement modifiés/génétique , Polluants du sol/toxicité , Polluants du sol/métabolisme , Graines/effets des médicaments et des substances chimiques , Graines/métabolisme , Régulation de l'expression des gènes végétaux/effets des médicaments et des substances chimiques , Stabilité protéique , Racines de plante/métabolisme , Racines de plante/effets des médicaments et des substances chimiques , Stress physiologique/effets des médicaments et des substances chimiques
7.
Adv Mater ; 36(35): e2406625, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38970526

RÉSUMÉ

Analogous to linear dielectric, amorphous perovskite dielectrics characterized of high breakdown strength and low remanent polarization possess in-depth application in the sea, land, and air fields. Amorphous engineering is a common approach to balance the inverse relationship between polarization and breakdown strength in dielectric ceramic capacitor, however, the low polarization is the major barrier limiting the improvement of energy storage density. To address this concern, the polymorphic localized heterostructure confirmed by high-resolution transmission electron microscope (HR-TEM) and HADDF images is constructed in BaTiO3-Bi(Ni0.5Zr0.5)O3 amorphous/nanocrystalline composite film with SiO2 addition (BT-BNZ-xS, x = 3, 5, 7, 10 mol%). The stability of nanocrystalline region achieved by Si-rich transition region and the enhancive ultra-short-range ordering in the amorphous region synergistically result in large breakdown strength and nonhysteretic polarized response. This polymorphic localized heterostructure optimizes the thermal stability in a wide temperature range and contributes ultrahigh energy storage density of 149.9 J cm-3 with markedly enhanced efficiency of 79.0%. This study provides a universal strategy to design the polarization behavior in other amorphous perovskite-based dielectrics.

8.
iScience ; 27(6): 110014, 2024 Jun 21.
Article de Anglais | MEDLINE | ID: mdl-38947512

RÉSUMÉ

The NAD+-dependent deacetylase SIRT7 is a pivotal regulator of DNA damage response (DDR) and a promising drug target for developing cancer therapeutics. However, limited progress has been made in SIRT7 modulator discovery. Here, we applied peptide-based deacetylase platforms for SIRT7 enzymatic evaluation and successfully identified a potent SIRT7 inhibitor YZL-51N. We initially isolated bioactive YZL-51N from cockroach (Periplaneta americana) extracts and then developed the de novo synthesis of this compound. Further investigation revealed that YZL-51N impaired SIRT7 enzymatic activities through occupation of the NAD+ binding pocket. YZL-51N attenuated DNA damage repair induced by ionizing radiation (IR) in colorectal cancer cells and exhibited a synergistic anticancer effect when used in combination with etoposide. Overall, our study not only identified YZL-51N as a selective SIRT7 inhibitor from insect resources, but also confirmed its potential use in combined chemo-radiotherapy by interfering in the DNA damage repair process.

9.
Kidney Int Rep ; 9(6): 1802-1809, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38899202

RÉSUMÉ

Introduction: The Mayo imaging classification model (MICM) requires a prestep qualitative assessment to determine whether a patient is in class 1 (typical) or class 2 (atypical), where patients assigned to class 2 are excluded from the MICM application. Methods: We developed a deep learning-based method to automatically classify class 1 and 2 from magnetic resonance (MR) images and provide classification confidence utilizing abdominal T 2 -weighted MR images from 486 subjects, where transfer learning was applied. In addition, the explainable artificial intelligence (XAI) method was illustrated to enhance the explainability of the automated classification results. For performance evaluations, confusion matrices were generated, and receiver operating characteristic curves were drawn to measure the area under the curve. Results: The proposed method showed excellent performance for the classification of class 1 (97.7%) and 2 (100%), where the combined test accuracy was 98.01%. The precision and recall for predicting class 1 were 1.00 and 0.98, respectively, with F 1 -score of 0.99; whereas those for predicting class 2 were 0.87 and 1.00, respectively, with F 1 -score of 0.93. The weighted averages of precision and recall were 0.98 and 0.98, respectively, showing the classification confidence scores whereas the XAI method well-highlighted contributing regions for the classification. Conclusion: The proposed automated method can classify class 1 and 2 cases as accurately as the level of a human expert. This method may be a useful tool to facilitate clinical trials investigating different types of kidney morphology and for clinical management of patients with autosomal dominant polycystic kidney disease (ADPKD).

10.
Int Immunopharmacol ; 136: 112264, 2024 Jul 30.
Article de Anglais | MEDLINE | ID: mdl-38810308

RÉSUMÉ

BACKGROUND: Chemotaxis and trafficking of dendritic cells (DCs) induced by cytokine receptors are crucial steps in rheumatoid arthritis (RA) pathogenesis. C-C chemokine receptor type 5 (CCR5) plays a key role in DC movement and has been implicated in multitudinous inflammatory and immunology diseases. Thus, targeting CCR5 to suppress DC chemotaxis is considered as a potential strategy for the management of RA. METHODS: Herein, we first synthesized a new hybrid named CT3-1 which based on artesunate and isatin. Besides, we studied the regulating effectiveness of CT3-1 on bone marrow-derived DCs (BMDCs) and on collagen-induced arthritis (CIA) through RNA-seq analysis, cell function experiments in vitro and mice model in vivo. RESULTS: The results shown that CT3-1 mainly reduced CCR5 expression of immature BMDCs and importantly inhibited immature BMDC migration induced by CCR5 in vitro, with no or minor influence on other functions of DCs, such as phagocytosis and maturation. In the mouse model, CT3-1 relieved arthritis severity and inhibited CIA development. Furthermore, CT3-1 intervention decreased the expression of CCR5 in DCs and reduced the proportion of DCs in the peripheral blood of CIA mice. CONCLUSIONS: Our findings suggest that CCR5-induced chemotaxis and trafficking of immature DCs are important in RA. Targeting CCR5 and inhibiting immature DC chemotaxis may provide a novel choice for the treatment of RA and other similar autoimmune diseases. Moreover, we synthesized a new hybrid compound CT3-1 that could inhibit immature DC trafficking and effectively relieve RA by directly reducing the CCR5 expression of immature DCs.


Sujet(s)
Artésunate , Arthrite expérimentale , Polyarthrite rhumatoïde , Chimiotaxie , Cellules dendritiques , Récepteurs CCR5 , Animaux , Cellules dendritiques/effets des médicaments et des substances chimiques , Cellules dendritiques/immunologie , Récepteurs CCR5/métabolisme , Arthrite expérimentale/traitement médicamenteux , Arthrite expérimentale/immunologie , Chimiotaxie/effets des médicaments et des substances chimiques , Artésunate/pharmacologie , Artésunate/usage thérapeutique , Souris , Polyarthrite rhumatoïde/traitement médicamenteux , Polyarthrite rhumatoïde/immunologie , Souris de lignée DBA , Mâle , Cellules cultivées , Humains
11.
Clin Res Cardiol ; 2024 May 13.
Article de Anglais | MEDLINE | ID: mdl-38740723

RÉSUMÉ

BACKGROUND: Both the clinical and mechanistic impacts of endocan were not well elucidated especially in coronary artery disease (CAD). OBJECTIVE: This study aimed to investigate the prognostic and potential pathological role of endocan for cardiovascular (CV) events in stable CAD patients. METHODS: A total of 1,071 stable CAD patients with previous percutaneous coronary intervention (PCI) were enrolled prospectively in a nationwide Biosignature study. Another cohort of 76 CAD patients with or without PCI were enrolled for validation. Baseline biomarkers including endocan level was measured and total CV events especially hard CV events (including CV mortality, non-fatal myocardial infection and stroke) during follow-up were identified. Circulating endothelial progenitor cells (EPCs) as an in vivo biological contributor to vascular repairment from CAD patients were used for the in vitro functional study. RESULTS: After 24 months, there were 42 patients (3.92%) with hard CV events and 207 (19.3%) with total CV events in the study group. The incidence of both events was increased with the tertiles of baseline endocan level (hard events: 1.7%,3.4%, and 6.7% in 1st,2nd, and 3rd tertile respectively, p = 0.002; total events: 13.8%vs.16.2%vs.28.0%, p < 0.0001). Multivariate regression analysis revealed the independent association of endocan level with total and hard CV events. These findings were validated in another cohort with a 5-year follow-up. Furthermore, in vitro inhibition of endocan improved cell migration and tube formation capacities, and reduced cell adhesiveness of EPCs from CAD patients. CONCLUSIONS: Endocan might be a novel prognostic indicator, mechanistic mediator, and potential therapeutic target for clinical CAD.

12.
J Nat Prod ; 87(4): 1103-1115, 2024 04 26.
Article de Anglais | MEDLINE | ID: mdl-38600744

RÉSUMÉ

Twelve new alkaloids, scolopenolines A-L (1-7, 9-11, 13, 14), along with six known analogues, were isolated from Scolopendra subspinipes mutilans, identified by analysis of spectroscopic data and quantum chemical and computational methods. Scolopenoline A (1), a unique guanidyl-containing C14 quinoline alkaloid, features a 6/6/5 ring backbone. Scolopenoline B (2) is a novel sulfonyl-containing heterodimer comprising quinoline and tyramine moieties. Scolopenoline G (7) presents a rare C12 quinoline skeleton with a 6/6/5 ring system. Alkaloids 1, 8, 10, and 15-18 display anti-inflammatory activity, while 10 and 16-18 also exhibit anti-renal-fibrosis activity. Drug affinity responsive target stability and RNA-interference assays show that Lamp2 might be a potentially important target protein of 16 for anti-renal-fibrosis activity.


Sujet(s)
Alcaloïdes , Animaux venimeux , Chilopoda , Animaux , Alcaloïdes/pharmacologie , Alcaloïdes/composition chimique , Alcaloïdes/isolement et purification , Structure moléculaire , Arthropodes/composition chimique , Fibrose/traitement médicamenteux , Rein/effets des médicaments et des substances chimiques , Quinoléines/pharmacologie , Quinoléines/composition chimique , Anti-inflammatoires/pharmacologie , Anti-inflammatoires/composition chimique , Humains
13.
Nanomaterials (Basel) ; 14(7)2024 Mar 22.
Article de Anglais | MEDLINE | ID: mdl-38607094

RÉSUMÉ

Chemical warfare agents (CWAs) refer to toxic chemical substances used in warfare. Recently, CWAs have been a critical threat for public safety due to their high toxicity. Metal-organic frameworks have exhibited great potential in protecting against CWAs due to their high crystallinity, stable structure, large specific surface area, high porosity, and adjustable structure. However, the metal clusters of most reported MOFs might be highly consumed when applied in CWA hydrolysis. Herein, we fabricated a two-dimensional piezoresponsive UiO-66-F4 and subjected it to CWA simulant dimethyl-4-nitrophenyl phosphate (DMNP) detoxification under sonic conditions. The results show that sonication can effectively enhance the removal performance under optimal conditions; the reaction rate constant k was upgraded 45% by sonication. Moreover, the first-principle calculation revealed that the band gap could be further widened with the application of mechanical stress, which was beneficial for the generation of 1O2, thus further upgrading the detoxification performance toward DMNP. This work demonstrated that mechanical vibration could be introduced to CWA protection, but promising applications are rarely reported.

14.
J Colloid Interface Sci ; 668: 88-97, 2024 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-38669999

RÉSUMÉ

Nanotheranostic platforms, which can respond to tumor microenvironments (TME, such as low pH and hypoxia), are immensely appealing for photodynamic therapy (PDT). However, hypoxia in solid tumors harms the treatment outcome of PDT which depends on oxygen molecules to generate cytotoxic singlet oxygen (1O2). Herein, we report the design of TME-responsive smart nanotheranostic platform (DOX/ZnO2@Zr-Ce6/Pt/PEG) which can generate endogenously hydrogen peroxide (H2O2) and oxygen (O2) to alleviate hypoxia for improving photodynamic-chemo combination therapy of tumors. DOX/ZnO2@Zr-Ce6/Pt/PEG nanocomposite was prepared by the synthesis of ZnO2 nanoparticles, in-situ assembly of Zr-Ce6 as typical metal-organic framework (MOF) on ZnO2 surface, in-situ reduction of Pt nanozymes, amphiphilic lipids surface coating and then doxorubicin (DOX) loading. DOX/ZnO2@Zr-Ce6/Pt/PEG nanocomposite exhibits average sizes of ∼78 nm and possesses a good loading capacity (48.8 %) for DOX. When DOX/ZnO2@Zr-Ce6/Pt/PEG dispersions are intratumorally injected into mice, the weak acidic TEM induces the decomposition of ZnO2 core to generate endogenously H2O2, then Pt nanozymes catalyze H2O2 to produce O2 for alleviating tumor hypoxia. Upon laser (630 nm) irradiation, the Zr-Ce6 component in DOX/ZnO2@Zr-Ce6/Pt/PEG can produce cytotoxic 1O2, and 1O2 generation rate can be enhanced by 2.94 times due to the cascaded generation of endogenous H2O2/O2. Furthermore, the generated O2 can suppress the expression of hypoxia-inducible factor α, and further enable tumor cells to become more sensitive to chemotherapy, thereby leading to an increased effectiveness of chemotherapy treatment. The photodynamic-chemo combination therapy from DOX/ZnO2@Zr-Ce6/Pt/PEG nanoplatform exhibits remarkable tumor growth inhibition compared to chemotherapy or PDT. Thus, the present study is a good demonstration of a TME-responsive nanoplatform in a multimodal approach for cancer therapy.


Sujet(s)
Doxorubicine , Peroxyde d'hydrogène , Oxygène , Photothérapie dynamique , Nanomédecine théranostique , Peroxyde d'hydrogène/composition chimique , Peroxyde d'hydrogène/métabolisme , Animaux , Souris , Doxorubicine/pharmacologie , Doxorubicine/composition chimique , Doxorubicine/administration et posologie , Oxygène/composition chimique , Oxygène/métabolisme , Humains , Photosensibilisants/composition chimique , Photosensibilisants/pharmacologie , Taille de particule , Propriétés de surface , Tests de criblage d'agents antitumoraux , Survie cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Peroxydes/composition chimique , Peroxydes/pharmacologie , Nanoparticules/composition chimique , Souris de lignée BALB C , Zinc/composition chimique , Zinc/pharmacologie , Microenvironnement tumoral/effets des médicaments et des substances chimiques , Antibiotiques antinéoplasiques/pharmacologie , Antibiotiques antinéoplasiques/composition chimique , Antibiotiques antinéoplasiques/administration et posologie
16.
Org Biomol Chem ; 22(13): 2678, 2024 Mar 27.
Article de Anglais | MEDLINE | ID: mdl-38483197

RÉSUMÉ

Correction and removal of expression of concern for 'Total synthesis of tubulysin U and N14-desacetoxytubulysin H' by Bohua Long et al., Org. Biomol. Chem., 2020, 18, 5349-5353, https://doi.org/10.1039/D0OB01109F.

17.
Sci Total Environ ; 924: 171686, 2024 May 10.
Article de Anglais | MEDLINE | ID: mdl-38485026

RÉSUMÉ

Methane-oxidizing bacteria (MOB) have long been considered as a microbial indicator for oil and gas prospecting. However, due to the phylogenetically narrow breath of ecophysiologically distinct MOB, classic culture-dependent approaches could not discriminate MOB population at fine resolution, and accurately reflect the abundance of active MOB in the soil above oil and gas reservoirs. Here, we presented a novel microbial anomaly detection (MAD) strategy to quantitatively identify specific indicator methylotrophs in the surface soils for bioprospecting oil and gas reservoirs by using a combination of 13C-DNA stable isotope probing (SIP), high-throughput sequencing (HTS), quantitative PCR (qPCR) and geostatistical analysis. The Chunguang oilfield of the Junggar Basin was selected as a model system in western China, and type I methanotrophic Methylobacter was most active in the topsoil above the productive oil wells, while type II methanotrophic Methylosinus predominated in the dry well soils, exhibiting clear differences between non- and oil reservoir soils. Similar results were observed by quantification of Methylobacter pmoA genes as a specific bioindicator for the prediction of unknown reservoirs by grid sampling. A microbial anomaly distribution map based on geostatistical analysis further showed that the anomalous zones were highly consistent with petroleum, geological and seismic data, and validated by subsequent drilling. Over seven years, a total of 24 wells have been designed and drilled into the targeted anomaly, and the success rate via the MAD prospecting strategy was 83 %. Our results suggested that molecular techniques are powerful tools for oil and gas prospecting. This study indicates that the exploration efficiency could be significantly improved by integrating multi-disciplinary information in geophysics and geomicrobiology while reducing the drilling risk to a greater extent.


Sujet(s)
Methylococcaceae , Pétrole , Champs de pétrole et de gaz , Méthane , Sol , Bioprospection , Microbiologie du sol , Phylogenèse , Oxydoréduction
18.
Microorganisms ; 12(2)2024 Feb 11.
Article de Anglais | MEDLINE | ID: mdl-38399776

RÉSUMÉ

Methane-oxidizing bacteria (MOB) have long been recognized as an important bioindicator for oil and gas exploration. However, due to their physiological and ecological diversity, the distribution of MOB in different habitats varies widely, making it challenging to authentically reflect the abundance of active MOB in the soil above oil and gas reservoirs using conventional methods. Here, we selected the Puguang gas field of the Sichuan Basin in Southwest China as a model system to study the ecological characteristics of methanotrophs using culture-independent molecular techniques. Initially, by comparing the abundance of the pmoA genes determined by quantitative PCR (qPCR), no significant difference was found between gas well and non-gas well soils, indicating that the abundance of total MOB may not necessarily reflect the distribution of the underlying gas reservoirs. 13C-DNA stable isotope probing (DNA-SIP) in combination with high-throughput sequencing (HTS) furthermore revealed that type II methanotrophic Methylocystis was the absolutely predominant active MOB in the non-gas-field soils, whereas the niche vacated by Methylocystis was gradually filled with type I RPC-2 (rice paddy cluster-2) and Methylosarcina in the surface soils of gas reservoirs after geoscale acclimation to trace- and continuous-methane supply. The sum of the relative abundance of RPC-2 and Methylosarcina was then used as specific biotic index (BI) in the Puguang gas field. A microbial anomaly distribution map based on the BI values showed that the anomalous zones were highly consistent with geological and geophysical data, and known drilling results. Therefore, the active but not total methanotrophs successfully reflected the microseepage intensity of the underlying active hydrocarbon system, and can be used as an essential quantitative index to determine the existence and distribution of reservoirs. Our results suggest that molecular microbial techniques are powerful tools for oil and gas prospecting.

19.
Bioorg Chem ; 144: 107169, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38330722

RÉSUMÉ

Four undescribed compounds including one aromatic glucoside derivative, cordyceglycoside A (1), one new isoleucine derivative inner salt, cordycepisosalt A (2), a rare four-membered lactam, cinerealactam B (3), and one sesquiterpene derivative, cordycepsetp A (4), together with six known compounds were isolated from Cordyceps militaris. The structures including absolute configurations of these new compounds, were unambiguously elucidated by spectroscopic data analysis and single crystal X-ray diffraction. Biological evaluation of compounds 1-4 showed that 3 displays anti-renal fibrotic activities in TGF-ß1 induced NRK-52e cells. Furthermore, DARTS coupled with LC-MS/MS analysis was used to identify candidate target proteins for 3. Subsequently, C1qbp knockdown using siRNA allowed us to validate the target protein of 3.


Sujet(s)
Cordyceps , Cordyceps/composition chimique , Cordyceps/métabolisme , Chromatographie en phase liquide , Spectrométrie de masse en tandem , Analyse spectrale , Fibrose
20.
Acta Biomater ; 177: 444-455, 2024 03 15.
Article de Anglais | MEDLINE | ID: mdl-38325709

RÉSUMÉ

Photodynamic therapy (PDT) is a clinically approved treatment for tumors, and it relies on the phototoxicity of photosensitizers by producing reactive oxygen species (ROS) to destroy cancer cells under light irradiation. However, such phototoxicity is a double-edged sword, which is also harmful to normal tissues. To manipulate phototoxicity and improve the therapy effect, herein we have proposed a dressing-undressing strategy for de-activating and re-activating therapy functions of photosensitizer nanoparticles. One kind of metal organic framework (PCN-224), which is composed of Zr(IV) cation and tetrakis (4-carboxyphenyl) porphyrin (TCPP), has been prepared as a model of photosensitizer, and it has size of ∼70 nm. These PCN-224 nanoparticles are subsequently coated with a mesoporous organic silica (MOS) shell containing tetrasulfide bonds (-S-S-S-S-), realizing the dressing of PCN-224. MOS shell has the thickness of ∼20 nm and thus can block 1O2 (diffusion distance: <10 nm), deactivating the phototoxicity and preventing the damage to skin and eyes. Furthermore, PCN-224@MOS can be used to load chemotherapy drug (DOX·HCl). When PCN-224@MOS-DOX are mixed with glutathione (GSH), MOS shell with -S-S-S-S- bonds can be reduced by GSH and then be decomposed, which results in the undressing and then confers the exposure of PCN-224 with good PDT function as well as the release of DOX. When PCN-224@MOS-DOX dispersion is injected into the mice and accumulated in the tumor, endogenous GSH also confers the undressing of PCN-224@MOS-DOX, realizing the in-situ activation of PDT and chemotherapy for tumor. Therefore, the present study not only demonstrates a general dressing-undressing strategy for manipulating phototoxicity of photosensitizers, but also provide some insights for precise therapy of tumors without side-effects. STATEMENT OF SIGNIFICANCE: Photosensitizers can generate reactive oxygen species (ROS) under light radiation to destroy cancer cells. However, this phototoxicity is a double-edged sword and also harmful to normal tissues such as the skin and eyes. To control phototoxicity and improve therapeutic efficacy, we prepared a PCN-224@MOS-DOX nanoplatform and proposed a dressing and undressing strategy to deactivate and reactivate the therapeutic function of the photosensitizer nanoparticles. The MOS shell can block the diffusion of 1O2, eliminate phototoxicity, and prevent damage to the skin and eyes. When injected into mice and accumulated in tumors, PCN-224@MOS-DOX dispersions are endowed with an endogenous GSH-driven undressing effect, achieving in situ activation of PDT and tumor chemotherapy.


Sujet(s)
Nanoparticules , Tumeurs , Photothérapie dynamique , Animaux , Souris , Photosensibilisants/composition chimique , Espèces réactives de l'oxygène , Tumeurs/traitement médicamenteux , Nanoparticules/usage thérapeutique , Nanoparticules/composition chimique , Oxygène , Silice/usage thérapeutique , Bandages , Lignée cellulaire tumorale
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