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1.
J Affect Disord ; 362: 437-449, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960335

RESUMO

BACKGROUND: Depression is a leading cause of disability and poor health worldwide and is expected to rank first worldwide by 2030. The aim of this study is to analyze the transition and trend of depression burden in China and various income-level countries by utilizing the Global Burden of Disease (GBD) database and the Joinpoint regression model. This analysis seeks to comprehend the variations in the burden of depression across different income regions and evaluate their developmental patterns. METHODS: Based on the GBD 2019 open dataset, this study extracted data on YLD (Years Lived with Disability), DALY (Disability-Adjusted Life Years), and incidence related to depression. The analysis focused on the period between 1990 and 2019, covering global data and distinguishing between high-income, upper-middle-income, lower-middle-income, low-income countries, and China. We utilized the Joinpoint regression model to fit the spatiotemporal trend changes among different income-level countries. Pairwise comparisons were conducted to examine the parallelism and to determine if the differences in trend changes among various regions were statistically significant. RESULTS: From 1990 to 2019, the age-standardized YLD and DALY for depression female were higher than that in male. The YLD total change rate of depression men was higher than that of women. China exhibited the largest disparity in total YLD change rates between genders, reaching 0.08. During 1990 to 2019, the incidence of depression in 2005-2019 increased among females in middle to high-income countries, low-income countries, and China as compare to that of 1990-2005. Notably, China shown the most increase the incidence rate of females (from -0.4 % to 0.84 %). China experienced the most significant change in the YLD of depression during this period (AAPC = 0.45, 95 % CI = 0.41, 0.48, P < 0.01). China's YLD/Incidence rate was higher compared to the global, HICs, UMCs, LMCs, and LICs. In China, the YLD/incidence rate of depression began to rise in 1994, peaking around 2010, and then gradually declining. Since 2010, the growth rate of depression DALYs in China has been higher than the global average, high-income countries, upper-middle-income countries, lower-middle-income countries, and low-income countries. The DALY's AAPC value for the HLCs was the highest (AAPC = 0.24, 95 % CI = 0.22, 0.25, P < 0.01). The UMCs, in comparison to other regions, incidence rate had the highest AAPC value (AAPC = 0.48, 95 % CI = 0.46, 0.50, P < 0.01). CONCLUSIONS: Given the significant variations in the burden of depression across countries with different income levels, future strategies aimed at reducing the burden of depression should adopt tailored and differentiated approaches according to each country's specific needs and developmental stages.

2.
Huan Jing Ke Xue ; 45(6): 3649-3660, 2024 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-38897784

RESUMO

This research aimed to clarify the effects of exogenously applied chitosan on the physiological characteristics, antioxidant activities, and Cd accumulation of wheat (Triticum aestivum L.) seedlings under cadmium (Cd) stress and to identify the key indicators based on the partial least squares model. The wheat variety studied was Bainong207 (BN207), and Cd-stress was achieved by growing seedlings in a hydroponic culture experiment with 10 and 25 µmol·L-1 Cd2+ added to the culture solution. It was found that both Cd-stress at 10 and 25 µmol·L-1 significantly inhibited the chlorophyll content, photosynthesis, and biomass accumulation of wheat seedlings. Seedling roots became shorter and thicker, and the lateral roots decreased under Cd-stress. The Cd-stress also increased H2O2 and MDA accumulation and the degree of cell membrane lipid peroxidation and affected the activities of antioxidant enzymes such as superoxide dismutase (SOD) and peroxidase (POD). Under Cd stress, exogenous chitosan decreased the Cd content in the aboveground and underground parts of wheat by 13.22 %-21.63 % and 7.92 %-28.32 % and reduced Cd accumulation in the aboveground and underground parts by 5.37 %-6.71 % and 1.91 %-4.09 %, respectively. Whereas exogenous chitosan application significantly reduced the content of H2O2 in roots and aboveground parts of wheat by 38.21 %-47.46 % and 45.81 %-55.73 % and MDA content by 37.65 %-48.12 % and 29.87 %-32.51 %, it increased the activities of SOD and POD in roots by 2.78 %-5.61 % and 13.81 %-18.33 %, respectively. In summary, exogenous chitosan can improve the photosynthetic characteristics and antioxidant enzyme activities of wheat seedlings under Cd stress, reduce the content and accumulation of Cd in the root and aboveground parts of wheat, and alleviate the damage of lipid peroxidation to the cell membrane. All of these results provide the basal data for the application of exogenous chitosan to alleviate Cd toxicity to wheat seedlings.


Assuntos
Antioxidantes , Cádmio , Quitosana , Plântula , Triticum , Triticum/metabolismo , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento , Cádmio/toxicidade , Cádmio/metabolismo , Quitosana/metabolismo , Quitosana/farmacologia , Plântula/efeitos dos fármacos , Plântula/metabolismo , Antioxidantes/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Poluentes do Solo/toxicidade , Poluentes do Solo/metabolismo
3.
Ophthalmol Sci ; 4(5): 100520, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881601

RESUMO

Purpose: Physiological changes in retinal ganglion cells (RGCs) have been reported in rodent models of photoreceptor (PR) loss, but this has not been investigated in primates. By expressing both a calcium indicator (GCaMP6s) and an optogenetic actuator (ChrimsonR) in foveal RGCs of the macaque, we reactivated RGCs in vivo and assessed their response in the weeks and years after PR loss. Design: We used an in vivo calcium imaging approach to record optogenetically evoked activity in deafferented RGCs in primate fovea. Cellular scale recordings were made longitudinally over a 10-week period after PR ablation and compared with responses from RGCs that had lost PR input >2 years prior. Participants: Three eyes received PR ablation, the right eye of a male Macaca mulatta (M1), the left eye of a female Macaca fascicularis (M2), and the right eye of a male Macaca fascicularis (M3). Two animals were used for in vivo recording, 1 for histological assessment. Methods: Cones were ablated with an ultrafast laser delivered through an adaptive optics scanning light ophthalmoscope (AOSLO). A 0.5 second pulse of 25 Hz 660 nm light optogenetically stimulated RGCs, and the resulting GCaMP fluorescence signal was recorded using an AOSLO. Measurements were repeated over 10 weeks immediately after PR ablation, at 2.3 years and in control RGCs. Main Outcome Measures: The calcium rise time, decay constant, and sensitivity index of optogenetic-mediated RGC were derived from GCaMP fluorescence recordings from 221 RGCs (animal M1) and 218 RGCs (animal M2) in vivo. Results: After PR ablation, the mean decay constant of the calcium response in RGCs decreased 1.5-fold (standard deviation 1.6 ± 0.5 seconds to 0.6 ± 0.3 seconds) over the 10-week observation period in subject 1 and 2.1-fold (standard deviation 2.5 ± 0.5 seconds to 1.2 ± 0.2 seconds) within 8 weeks in subject 2. Calcium rise time and sensitivity index were stable. Optogenetic reactivation remained possible 2.3 years after PR ablation. Conclusions: Altered calcium dynamics developed in primate foveal RGCs in the weeks after PR ablation. The mean decay constant of optogenetic-mediated calcium responses decreased 1.5- to twofold. This is the first report of this phenomenon in primate retina and further work is required to understand the role these changes play in cell survival and activity. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

4.
Discov Med ; 36(182): 527-537, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38531793

RESUMO

BACKGROUND: The clinical outcomes of chemotherapy (CT) for the treatment of metastatic triple-negative (TN) and hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (mBC) have proven to be disappointing. The phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway, a tumor-promoting signaling cascade frequently mutated in breast cancer (BC), has been implicated in chemoresistance. In this study, our objective is to investigate the efficacy and safety of combining everolimus with chemotherapy in mBC patients exhibiting mutations in the PI3K/AKT/mTOR pathway. METHODS: We conducted a retrospective analysis to characterize the efficacy, safety, and their association with clinical and molecular characteristics of metastatic lesions in 14 patients with HER2- mBC. These patients harbored at least one altered member of the PI3K/AKT/mTOR signaling pathway and were treated with a combination of a chemotherapy agent and the mTOR inhibitor everolimus (CT+EVE). RESULTS: The majority of patients belonged to the triple-negative (TN) subtype (9/14, 64.3%), having already undergone 2 lines of chemotherapy (CT) in the metastatic setting (11, 78.6%). These patients carried altered phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) and were administered a vinorelbine-containing regimen (10, 71.4%). The objective response rate (ORR) was 42.9%, with a disease control rate of 92.9%. The median progression-free survival (PFS) and overall survival (OS) were 5.9 (95% confidence interval (CI): 4.9-13.6) months and 14.3 (95% CI: 8.5-not reached (NR)) months, respectively. Patients with fewer prior treatment lines tended to exhibit longer PFS. OS, PFS, and ORR were comparable between hormone receptor-positive (HR+) and triple-negative breast cancer (TNBC) patients, but numerical improvements were noted in patients with a single PI3K pathway alteration compared to those with more than one alteration. Genomic alterations that surfaced upon progression on CT+EVE included cyclin dependent kinase 4 (CDK4) and epidermal growth factor receptor (EGFR) amplification, as well as neurofibromin 1 (NF1) mutation, suggesting potential mechanisms of acquired resistance. An analysis of adverse events indicated manageable toxicities. CONCLUSIONS: The findings of this study suggest both activity and safety for the combination of chemotherapy and the mTOR inhibitor everolimus (CT+EVE) in patients with HER2- mBC who have alterations in the PI3K pathway, particularly those who have received fewer prior chemotherapy. However, it is crucial to note that large-scale, randomized control studies are warranted to more comprehensively characterize the efficacy and safety of this combination therapy.


Assuntos
Neoplasias da Mama , Everolimo , Humanos , Feminino , Everolimo/uso terapêutico , Neoplasias da Mama/patologia , Proteínas Proto-Oncogênicas c-akt/uso terapêutico , Fosfatidilinositol 3-Quinases , Estudos Retrospectivos , Receptor ErbB-2/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Serina-Treonina Quinases TOR
5.
Huan Jing Ke Xue ; 45(2): 1141-1149, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471951

RESUMO

This research aimed to clarify the mitigative effect of exogenously applied rare earth element cerium (Ce) on the growth, zinc (Zn) accumulation, and physiological characteristics of wheat (Triticum aestivum L.) seedlings under Zn stress. The wheat variety studied was Bainong307 (BN307), and Zn stress was achieved by growing seedlings in a hydroponic culture experiment with 500 µmol·L-1 Zn2 + added to the culture solution. It was found that Zn stress at 500 µmol·L-1 significantly inhibited the chlorophyll content, photosynthesis, and biomass accumulation of wheat seedlings. Seedling roots became shorter and thicker, and the lateral roots decreased under Zn stress. The Zn stress also increased MDA accumulation and the degree of cell membrane lipid peroxidation and reduced soluble protein contents and the activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). On the contrary, exogenous Ce decreased the adsorption and transport of Zn by the root system and alleviated the damage of Zn stress to wheat seedlings. Specifically, the increase in chlorophyll content (chlorophyll a, chlorophyll b, and total chlorophyll) and photosynthetic parameters, the enhancement of antioxidant enzymes activities and soluble protein levels, and the reduction in MDA content and the damage of lipid peroxidation to the cell membrane were all driven by exogenous Ce, which ultimately led to the increase in dry matter biomass of the root system and shoot. In summary, these results provide basic data for the application of exogenous Ce to alleviate Zn toxicity to plants.


Assuntos
Cério , Zinco , Zinco/metabolismo , Antioxidantes/metabolismo , Plântula , Triticum , Cério/metabolismo , Cério/farmacologia , Clorofila A , Superóxido Dismutase/metabolismo , Clorofila , Estresse Oxidativo
6.
J Org Chem ; 89(7): 4484-4495, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38470436

RESUMO

Nickel-catalyzed carbonylation of alkenes is a stereoselective and regioselective method for the synthesis of amide compounds. Theoretical predictions with density functional theory calculations revealed the mechanism and origin of stereoselectivity and regioselectivity for the nickel-catalyzed carbonylation of norbornene. The carbonylation reaction proceeds through oxidative addition, migration insertion of alkenes, and subsequent reduction elimination to afford cis-carbonylation product. The C-N bond activation of amides is unfavorable because the oxidative addition ability of the C-C bond is stronger than that of the C-N bond. The determining step of stereoselectivity is the migratory insertion of the strained olefin. The structural analysis shows that steroselectivity is controlled by the steric hindrance of methyl groups to olefins and substituents to IMes in ligands.

7.
Heliyon ; 10(1): e23659, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38173505

RESUMO

Sphingolipid metabolism affects prognosis and resistance to immunotherapy in patients with cancer and is an emerging target in cancer therapy with promising diagnostic and prognostic value. Long noncoding ribonucleic acids (lncRNAs) broadly regulate tumour-associated metabolic reprogramming. However, the potential of sphingolipid metabolism-related lncRNAs in pancreatic adenocarcinoma (PAAD) is poorly understood. In this study, coexpression algorithms were employed to identify sphingolipid metabolism-related lncRNAs. The least absolute shrinkage and selection operator (LASSO) algorithm was used to develop a sphingolipid metabolism-related lncRNA signature (SMLs). The prognostic predictive stability of the SMLs was validated using Kaplan-Meier. Univariate and multivariate Cox, receiver operating characteristic (ROC) and clinical stratification analyses were used to comprehensively assess the SMLs. Gene set variation analysis (GSVE), gene ontology (GO) and tumor mutation burden (TMB) analysis explored the potential mechanisms. Additionally, single sample gene set enrichment analysis (ssGSEA), ESTIMATE, immune checkpoints and drug sensitivity analysis were used to investigate the potential predictive function of the SMLs. Finally, an SMLs-based consensus clustering algorithm was utilized to differentiate patients and determine the suitable population for immunotherapy. The results showed that the SMLs consists of seven sphingolipid metabolism-related lncRNAs, which can well determine the clinical outcome of individuals with PAAD, with high stability and general applicability. In addition, the SMLs-based consensus clustering algorithm divided the TCGA-PAAD cohort into two clusters, with Cluster 1 showing better survival than Cluster 2. Additionally, Cluster 1 had a higher level of immune cell infiltration than Cluster 2, which combined with the higher levels of immune checkpoints in Cluster 1 suggests that Cluster 1 is more consistent with an immune 'hot tumor' profile and may respond better to immune checkpoint inhibitors (ICIs). This study offers new insights regarding the potential role of sphingolipid metabolism-related lncRNAs as biomarkers in PAAD. The constructed SMLs and the SMLs-based clustering are valuable tools for predicting clinical outcomes in PAAD and provide a basis for clinical selection of individualized treatments.

8.
Aging (Albany NY) ; 16(3): 2410-2437, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38284890

RESUMO

BACKGROUND: PANoptosis is involved in the interaction of apoptosis, necroptosis and pyroptosis, playing a role in programmed cell death. Moreover, long non-coding RNAs (lncRNAs) regulate the PCD. This work aims to explore the role of PANoptosis-associated lncRNAs in hepatocellular carcinoma (HCC). METHODS: Co-expression analysis identified PANoptosis-associated lncRNAs in HCC. Cox and Least Absolute Shrinkage and Selection Operator (LASSO) algorithms were utilised to filter lncRNAs and establish a PANoptosis-related lncRNA index (PANRI). Additionally, Cox, Kaplan-Meier and receiver operating characteristic (ROC) curves were utilised to systematically evaluate the PANRI. Furthermore, Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE), single sample gene set enrichment analysis (ssGSEA) and immune checkpoints were performed to analyse the potential of the PANRI in differentiating different tumour immune microenvironment (TIME) populations. The consensus clustering algorithm was used to distinguish individuals with HCC having different TIME subtypes. Finally, HCC cell lines HepG2 were utilised for further validation in in vitro experiments. RESULTS: The PANRI differentiates patients according to risk. Notably, ESTIMATE and ssGSEA algorithms revealed a high immune infiltration status in high-risk patients. Additionally, consensus clustering divided the patients into three clusters to identify different subtypes of TIME. Moreover, in vitro results showed that siRNA-mediated silencing of AL049840.4 inhibited the viability and migration of HepG2 cells and promoted apoptosis. CONCLUSIONS: This is the first PANoptosis-related, lncRNA-based risk index in HCC to assess patient prognosis, TIME and response to immunotherapy. This study offers novel perspectives on the role of PANoptosis-associated lncRNAs in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Medicina de Precisão , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Prognóstico , Microambiente Tumoral/genética
9.
IEEE Trans Biomed Eng ; 71(6): 1879-1888, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38231824

RESUMO

To improve the signal collection efficiency of Optical Coherence Tomography (OCT) for biomedical applications. A novel coaxial optical design was implemented, utilizing a wavefront-division beam splitter in the sample arm with a 45-degree rod mirror. This design allowed for the simultaneous collection of bright and dark field signals. The bright field signal was detected within its circular aperture in a manner similar to standard OCT, while the dark field signal passed through an annular-shaped aperture and was collected by the same spectrometer via a fiber array. This new configuration improved the signal collection efficiency by ∼3 dB for typical biological tissues. Dark-field OCT images were found to provide higher resolution, contrast and distinct information compared to standard bright-field OCT. By compounding bright and dark field images, speckle noise was suppressed by ∼ √2 . These advantages were validated using Teflon phantoms, chicken breast ex vivo, and human skin in vivo. This new OCT configuration significantly enhances signal collection efficiency and image quality, offering great potential for improving OCT technology with better depth, contrast, resolution, speckles, and signal-to-noise ratio. We believe that the bright and dark field signals will enable more comprehensive tissue characterization with the angled scattered light. This advancement will greatly promote the OCT technology in various clinical and biomedical research applications.


Assuntos
Galinhas , Desenho de Equipamento , Imagens de Fantasmas , Tomografia de Coerência Óptica , Tomografia de Coerência Óptica/métodos , Tomografia de Coerência Óptica/instrumentação , Animais , Humanos , Pele/diagnóstico por imagem , Razão Sinal-Ruído , Processamento de Sinais Assistido por Computador , Processamento de Imagem Assistida por Computador/métodos
10.
bioRxiv ; 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-37398439

RESUMO

Objective or purpose: Physiological changes in retinal ganglion cells (RGCs) have been reported in rodent models of photoreceptor (PR) loss but this has not been investigated in primates. By expressing both a calcium indicator (GCaMP6s) and an optogenetic actuator (ChrimsonR) in foveal RGCs of the macaque, we reactivated RGCs in vivo and assessed their response in the weeks and years following PR loss. Design: We used an in vivo calcium imaging approach to record optogenetically evoked activity in deafferented RGCs in primate fovea. Cellular scale recordings were made longitudinally over a 10 week period following photoreceptor ablation and compared to responses from RGCs that had lost photoreceptor input more than two years prior. Participants: Three eyes received photoreceptor ablation, OD of a male Macaca mulatta (M1), OS of a female Macaca fascicularis (M2) and OD of a male Macaca fascicularis (M3). Two animals were used for in vivo recording, one for histological assessment. Methods: Cones were ablated with an ultrafast laser delivered through an adaptive optics scanning light ophthalmoscope (AOSLO). A 0.5 s pulse of 25Hz 660nm light optogenetically stimulated RGCs, and the resulting GCaMP fluorescence signal was recorded using AOSLO. Measurements were repeated over 10 weeks immediately after PR ablation, at 2.3 years and in control RGCs. Main Outcome measures: The calcium rise time, decay constant and sensitivity index of optogenetic mediated RGC were derived from GCaMP fluorescence recordings from 221 RGCs (Animal M1) and 218 RGCs (Animal M2) in vivo. Results: Following photoreceptor ablation, the mean decay constant of the calcium response in RGCs decreased 1.5 fold (1.6±0.5 s to 0.6±0.3 s SD) over the 10 week observation period in subject 1 and 2.1 fold (2.5±0.5 s to 1.2±0.2 s SD) within 8 weeks in subject 2. Calcium rise time and sensitivity index were stable. Optogenetic reactivation remained possible 2.3 years after PR ablation. Conclusions: Altered calcium dynamics developed in primate foveal RGCs in the weeks after photoreceptor ablation. The mean decay constant of optogenetic mediated calcium responses decreased 1.5 - 2-fold. This is the first report of this phenomenon in primate retina and further work is required to understand the role these changes play in cell survival and activity.

11.
Inorg Chem ; 62(44): 18198-18208, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37871926

RESUMO

A series of cyclometalated C,N-chelate half-sandwich ruthenium complexes based on N-heterocyclic ligands were prepared through a simple route with good yields. These air- and moisture-stable cyclometalated ruthenium complexes showed excellent catalytic efficiency in phenoxy carbonylation of aryl halides with phenyl formate derivatives as a CO source and phenol as a coupling partner under air. Ester products were obtained with high yields at room temperature and without the need for an inert atmosphere. The excellent catalytic activity, broad substrate range, and mild reaction conditions made this catalytic system potential for industrial production. In addition, DFT study has been carried out to elaborate the possible mechanism of this Ru-catalyzed reaction.

12.
Appl Opt ; 62(24): 6447-6455, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37706838

RESUMO

Real-time 3D reconstruction has been applied in many fields, calling for many ongoing efforts to improve the speed and accuracy of the used algorithms. Phase shifting profilometry based on the Lucas-Kanade optical flow method is a fast and highly precise method to construct and display the three-dimensional shape of objects. However, in this method, a dense optical flow calculation is required for the modulation image corresponding to the acquired deformed fringe pattern, which consumes a lot of time and affects the real-time performance of 3D reconstruction and display. Therefore, this paper proposes a dynamic 3D phase shifting profilometry based on a corner optical flow algorithm to mitigate this issue. Therein, the Harris corner algorithm is utilized to locate the feature points of the measured object, so that the optical flow needs to calculate for only the feature points which, greatly reduces the amount of calculation time. Both our experiments and simulations show that our method improves the efficiency of pixel matching by four times and 3D reconstruction by two times.

13.
J Org Chem ; 88(19): 14115-14130, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37766467

RESUMO

The Ni-catalyzed alkylboration of endocyclic olefins is a stereo- and regioselective approach for the synthesis of boron-containing compounds. We report a detailed density functional theory (DFT) study to elucidate the mechanism and origins of the stereo-, chemo-, and regioselectivity of alkylboration of endocyclic olefins enabled by nickel catalysis. The alkylboration proceeds via the migratory insertion of alkenes, ß-H elimination of the Ni(II) complex, subsequent migratory insertion leading to a new Ni(II) complex, combined with an alkyl radical, and reductive eliminations. The electronic effects of the endocyclic olefins synergistically control the regioselectivity toward the C1- and C2-position boration. In C1-position boration, a more electron-deficient carbon atom tends to combine with an electron-rich -Bpin group and leads to C1-position boration products. The stereoselectivity is influenced by the solvent effect, and the interaction between the substrate and Ni-catalyzed groups, the low-polarity solvent 1,4-dioxane, and a favorable steric hindrance effect result in the cis-alkylboration product. Chemoselectivity toward 1,3-alkylboration results from the steric hindrance effects of the -Bpin group.

14.
bioRxiv ; 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37546797

RESUMO

Though the responses of the rich variety of retinal ganglion cells (RGCs) reflect the totality of visual processing in the retina and provide the sole conduit for those processed responses to the brain, we have much to learn about how the brain uses these signals to guide behavior. An impediment to developing a comprehensive understanding of the role of retinal circuits in behavior is the paucity of causal studies in the intact primate visual system. Here we demonstrate the ability to optogenetically activate individual RGCs with flashes of light focused on single RGC somas in vivo , without activation of neighboring cells. The ability to selectively activate specific cells is the first step toward causal experiments that directly link retinal circuits to visual experience and behavior.

15.
Materials (Basel) ; 15(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36431633

RESUMO

Electrochemical polishing (ECP) is an efficient and low-cost technology for polishing difficult-to-machine materials with complex structures. However, when an environmentally friendly neutral salt solution is used as the polishing electrolyte, a dense passivation film forms on the surface of passive metals, such as titanium alloy, with a serious detrimental effect on the polishing efficiency and surface quality. In this paper, we introduce an ECP method assisted by a high-speed flow of micro-abrasive particles (ECFAP). The contribution of the flowing micro-abrasive particles in the ECP process enables the electrochemical dissolution and abrasive polishing to occur simultaneously on the workpiece surface. The high-speed abrasive particles remove the passivation film formed under ECP, thereby improving the polishing efficiency and quality. We carried out the comparative tests of conventional ECP and the proposed ECFAP on a Ti6Al4V alloy in 10% NaNO3 electrolyte; the results show that, while the matrix material forms a soft high-impedance passivation film under ECP, this film is removed by the high-speed flowing abrasive particles under ECFAP. The proposed ECFAP method improves both the polishing efficiency and the surface quality. Finally, ECFAP-treated specimens with an optimum voltage of 3 V for 10 min exhibited an average surface roughness of 0.0953 µm.

16.
Anticancer Drugs ; 33(10): 1004-1011, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36255067

RESUMO

GNG5 is suggested to exert a critical effect on tumor development in human beings; however, its function and related mechanism within breast cancer (BC) are still unclear. In this regard, the present work focused on identifying and evaluating GNG5's function and revealing its possible molecular mechanism. Subcutaneous tumorigenesis model of nude mice and in-vitro cell model was established. The relationship between GNG5 expression and BC was studied through knockdown and overexpression experiments. The proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of liver cancer cell lines overexpressing or silencing GNG5 were detected. Furthermore, the pathway mechanism of GNG5 was evaluated at the molecular level and was performed to further verify the possible targets and mechanisms of action. In comparison with that in normal tissue, GNG5 level within BC tissue was higher. In addition, GNG5 overexpression stimulated BC cell proliferation, invasion, migration and EMT. BC cells with reduced GNG5 expression exhibited significant decreases in glucose uptake, lactate levels, and ATP concentrations. In addition, GNG5 knockdown inhibited Wnt/ß-catenin signaling. This study indicates that GNG5 may generate a vital function in BC. The results of the current work demonstrated GNG5's effect on BC pathological process, also providing a reference for developing new targeted therapies for BC.


Assuntos
Neoplasias da Mama , Subunidades gama da Proteína de Ligação ao GTP , Via de Sinalização Wnt , Animais , Feminino , Humanos , Camundongos , Trifosfato de Adenosina/metabolismo , beta Catenina/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Glucose , Glicólise , Lactatos/farmacologia , Camundongos Nus , Subunidades Proteicas/metabolismo , Subunidades gama da Proteína de Ligação ao GTP/metabolismo
17.
Ecotoxicol Environ Saf ; 244: 114037, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36049335

RESUMO

Nickel is a common heavy metal pollutant in industrial areas and can cause oxidative damage to human and animal organs. As an essential amino acid with antioxidant function, methionine (Met) may protect the body from the oxidative stress induce by nickel, however, there is not enough research to study in this aspect. The study aims at investigating the effect of Met on the nickel-induced intestinal oxidative stress and further detected the gut microbiota changes. Mice were gavaged with quantitative NiCl2 (1.6 mg/ml, 0.25 ml) and fed with different doses of methionine in each group. The contents of intestinal oxidation product and antioxidant enzymes were determined by different biochemical quantitative methods, and the data showed that NiCl2 increased the content of intestinal oxidation product (MDA), and the antioxidant enzymes (GSH-Px, GR, SOD and CAT) were decreased. But this situation was alleviated in the group fed with additional methionine solution (0.5 mg/ml). In addition, we detected changes in the gut microbiota using high-throughput sequencing, the results showed that the structure of intestinal flora was disturbed by NiCl2, but methionine restored the germs with antioxidant capacity. Based on the results, we speculate that methionine can alleviate the impact of NiCl2 on the intestinal by enhancing the activity of antioxidant enzymes and the number of gut bacteria with anti-oxidation, suggesting that methionine as a nutritional additive may have the potential to treat nickel poisoning.


Assuntos
Poluentes Ambientais , Microbioma Gastrointestinal , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Galinhas/metabolismo , Poluentes Ambientais/farmacologia , Humanos , Metionina/metabolismo , Metionina/farmacologia , Camundongos , Níquel/toxicidade , Estresse Oxidativo , Racemetionina/metabolismo , Racemetionina/farmacologia , Superóxido Dismutase/metabolismo
18.
Medicine (Baltimore) ; 101(33): e28659, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35984121

RESUMO

3-dimention (3D) Cube isotropic volumetric magnetic resonance imaging (MRI) facilitates comprehensive recognition of microinfarcts while it takes long scanning time. HyperSense compressed sensing is an emerging technique for accelerating MRI acquisition to reduce scanning time, while its application along with 3D Cube MRI for microinfarcts is seldom reported. Therefore, this study aimed to investigate the efficiency of 3D Cube FLAIR plus HyperSense compressed sensing technique versus conventional 2-dimention (2D) FLAIR scanning in the detection of cortical microinfarcts (CMIs). Totally 59 patients with cerebrovascular disease were enrolled then scanned by 3D Cube FLAIR plus HyperSense compressed sensing and 2D T2WI FLAIR sequences. The image quality scores, signal-to-noise ratio (SNR) for gray matter (GM), SNR for white matter (WM), their contrast-to-noise ratio (WM-to-GM CNR), detected number of CMIs were evaluated. 3D Cube FLAIR plus HyperSense showed a dramatically increased scores of uniformity, artifact, degree of lesion displacement, and overall image quality compared to 2D T2WI FLAIR. Meanwhile, it exhibited similar SNRwm and SNRgm, but a higher WM-to-GM contrast-to-noise ratio compared with 2D T2WI FLAIR. Furthermore, the scanning time of 3D Cube FLAIR plus HyperSense and 2D T2WI FLAIR were both set as 2.5 minutes. Encouragingly, 244 CMIs were detected by 3D Cube FLAIR plus HyperSense, which was higher compared to 2D T2WI FLAIR (106 detected CMIs). 3D Cube FLAIR plus HyperSense compressed sensing is superior to 2D T2WI FLAIR scanning regarding image quality, spatial resolution, detection rate for CMIs; meanwhile, it does not increase the scanning time. These findings may contribute to early detection and treatment of stroke.


Assuntos
Imageamento Tridimensional , Substância Branca , Substância Cinzenta , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Razão Sinal-Ruído
19.
Cell Discov ; 8(1): 59, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732626

RESUMO

Granulocyte colony-stimulating factor (G-CSF) has been widely used to mobilize bone marrow hematopoietic stem/progenitor cells for transplantation in the treatment of hematological malignancies for decades. Additionally, G-CSF is also accepted as an essential mediator in immune regulation, leading to reduced graft-versus-host disease following transplantation. Despite the important clinical roles of G-CSF, a comprehensive, unbiased, and high-resolution survey into the cellular and molecular ecosystem of the human G-CSF-primed bone marrow (G-BM) is lacking so far. Here, we employed single-cell RNA sequencing to profile hematopoietic cells in human bone marrow from two healthy donors before and after 5-day G-CSF administration. Through unbiased bioinformatics analysis, our data systematically showed the alterations in the transcriptional landscape of hematopoietic cells in G-BM, and revealed that G-CSF-induced myeloid-biased differentiation initiated from the stage of lymphoid-primed multipotent progenitors. We also illustrated the cellular and molecular basis of hyporesponsiveness of T cells and natural killer (NK) cells caused by G-CSF stimulation, including the potential direct mechanisms and indirect regulations mediated by ligand-receptor interactions. Taken together, our data extend the understanding of lymphomyeloid divergence and potential mechanisms involved in hyporesponsiveness of T and NK cells in human G-BM, which might provide basis for optimization of stem cell transplantation in hematological malignancy treatment.

20.
J Oncol ; 2022: 7633720, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401746

RESUMO

The aim of this study was to explore the regulatory role of epoxide hydrolase 3 (EPHX3) in head and neck squamous cell carcinoma (HNSCC) and to analyze its bioinformatic function, as well as, to screen and predict the miRNAs that can regulate EPHX3 expression in HNSCC. We examined the expression profile and prognostic potential of EPHX3 in TCGA and GTEX databases and performed functional enrichment analysis of EPHX3 using string database. Subsequently, we analyzed the regulatory role of miRNAs on EPHX3, including expression analysis, correlation analysis, and survival analysis. In addition, we also used TIMER to investigate the relationship among EPHX3 expression level, immune checkpoints, and immune infiltration in HNSCC. The results of data analysis after TGCA showed that EPHX3 is a key regulator of tumorigenesis in 13 cancers and can be used as a marker of poor prognosis in HNSCC patients. Bioinformatics analysis revealed that miR-4713-3p is a key miRNA of EPHX3 in HNSCC. Together, our findings indicate that EPHX3 exerts its anticancer effects by suppressing tumor immune checkpoint expression and immune cell infiltration. Overall, our data uncovered miRNA-mediated EPHX3 downregulation as a contributor to poor HNSCC prognosis and reduced tumor immune infiltration.

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