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1.
J Cell Physiol ; 239(2): e31129, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38192063

RESUMO

Myelodysplastic syndromes (MDS) are a group of heterogeneous myeloid clonal disorders characterized by ineffective hematopoiesis. Accumulating evidence has shown that macrophages (MΦs) are important components in the regulation of tumor progression and hematopoietic stem cells (HSCs). However, the roles of bone marrow (BM) MΦs in regulating normal and malignant hematopoiesis in different clinical stages of MDS are largely unknown. Age-paired patients with lower-risk MDS (N = 15), higher-risk MDS (N = 15), de novo acute myeloid leukemia (AML) (N = 15), and healthy donors (HDs) (N = 15) were enrolled. Flow cytometry analysis showed increased pro-inflammatory monocyte subsets and a decreased classically activated (M1) MΦs/alternatively activated (M2) MΦs ratio in the BM of patients with higher-risk MDS compared to lower-risk MDS. BM MФs from patients with higher-risk MDS and AML showed impaired phagocytosis activity but increased migration compared with lower-risk MDS group. AML BM MΦs showed markedly higher S100A8/A9 levels than lower-risk MDS BM MΦs. More importantly, coculture experiments suggested that the HSC supporting abilities of BM MΦs from patients with higher-risk MDS decreased, whereas the malignant cell supporting abilities increased compared with lower-risk MDS. Gene Ontology enrichment comparing BM MΦs from lower-risk MDS and higher-risk MDS for genes was involved in hematopoiesis- and immunity-related pathways. Our results suggest that BM MΦs are involved in ineffective hematopoiesis in patients with MDS, which indicates that repairing aberrant BM MΦs may represent a promising therapeutic approach for patients with MDS.


Assuntos
Infecções , Macrófagos , Síndromes Mielodisplásicas , Humanos , Medula Óssea/patologia , Hematopoese , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Macrófagos/patologia , Síndromes Mielodisplásicas/genética , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Infecções/patologia
2.
BMC Med ; 22(1): 176, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664766

RESUMO

BACKGROUND: There is an urgent unmet need for effective initial treatment for acute graft-versus-host disease (aGVHD) adding to the standard first-line therapy with corticosteroids after allogeneic haematopoietic stem cell transplantation (allo-HSCT). METHODS: We performed a multicentre, open-label, randomized, phase 3 study. Eligible patients (aged 15 years or older, had received allo-HSCT for a haematological malignancy, developed aGVHD, and received no previous therapies for aGVHD) were randomly assigned (1:1) to receive either 5 mg/m2 MTX on Days 1, 3, or 8 and then combined with corticosteroids or corticosteroids alone weekly. RESULTS: The primary endpoint was the overall response rate (ORR) on Day 10. A total of 157 patients were randomly assigned to receive either MTX plus corticosteroids (n = 78; MTX group) or corticosteroids alone (n = 79; control group). The Day 10 ORR was 97% for the MTX group and 81% for the control group (p = .005). Among patients with mild aGVHD, the Day 10 ORR was 100% for the MTX group and 86% for the control group (p = .001). The 1-year estimated failure-free survival was 69% for the MTX group and 41% for the control group (p = .002). There were no differences in treatment-related adverse events between the two groups. CONCLUSIONS: In conclusion, mini-dose MTX combined with corticosteroids can significantly improve the ORR in patients with aGVHD and is well tolerated, although it did not achieve the prespecified 20% improvement with the addition of MTX. TRIAL REGISTRATION: The trial was registered with clinicaltrials.gov (NCT04960644).


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Metotrexato , Metilprednisolona , Humanos , Doença Enxerto-Hospedeiro/tratamento farmacológico , Feminino , Masculino , Metotrexato/administração & dosagem , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Adulto , Metilprednisolona/uso terapêutico , Metilprednisolona/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adulto Jovem , Resultado do Tratamento , Quimioterapia Combinada , Idoso , Adolescente , Doença Aguda
3.
Small ; 20(40): e2401134, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38816761

RESUMO

Strain engineering has been widely used to optimize platinum-based oxygen reduction reaction (ORR) catalysts for proton exchange membrane fuel cells (PEMFCs). PtM3 (M is base metals), a well-known high-compressive-strain intermetallic alloy, shows promise as a low platinum ORR catalyst due to high intrinsic activity. However, during the alloying of Pt with a threefold amount of M, a notable phase separation between Pt and M may occur, with M particles rapidly sintering while Pt particles grow slowly, posing a challenge in achieving a well-defined PtM3 intermetallic alloy. Here, an entropy-driven Ostwald ripening reversal phenomenon is discovered that enables the synthesis of small-sized Pt(FeCoNiCu)3 intermetallic ORR catalysts. High entropy promotes the thermodynamic driving force for the alloying Pt with M, which triggers the Ostwald ripening reversal of sintered FeCoNiCu particles and facilitates the formation of uniform Pt(FeCoNiCu)3 intermetallic catalysts. The prepared Pt(FeCoNiCu)3 catalysts exhibit a high specific activity of 3.82 mA cm-2, along with a power density of ≈1.3 W cm-2 at 0.67 V and 94 °C with a cathode Pt loading of 0.1 mg cm-2 in H2-air fuel cell.

4.
J Viral Hepat ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373164

RESUMO

Low-level viraemia (LLV) occurs in chronic hepatitis B (CHB) patients despite antiviral treatment, which may cause failed histological regression. Our study aimed to investigate the impact of different LLV types on fibrosis regression. The prospective study enrolled CHB patients with paired liver biopsies before and after 260 weeks of entecavir treatment. Fibrosis regression was defined by the Ishak score or P-I-R system. Patients were grouped as the SVR (HBV DNA < 20 IU/mL persistently) or LLV (HBV DNA between 20 and 2000 IU/mL), which were further grouped as very low-level viraemia (VLLV, HBV DNA < 50 IU/mL), occasionally LLV (OLLV, HBV DNA ≥ 50 IU/mL only once) and multiple LLV (MLLV, HBV DNA ≥ 50 IU/mL more than once). Logistic regression models were used to calculate the adjusted odds ratios (aORs) and 95% confidence intervals (CIs). The analysis included 111 CHB patients. In the SVR group (n = 54), 39 (72.2%) patients had fibrosis regression, which was higher than the LLV (56.1%, p = 0.080). The fibrosis regression rates for VLLV (30 patients), OLLV (17 patients) and MLLV (10 patients) were 70.0%, 52.9% and 30.0%, respectively. Compared with SVR, VLLV (aOR = 0.78; 95% CI: 0.28-2.21; p = 0.644) was not associated with fibrosis regression, but patients with non-VLLV (aOR = 0.27; 95% CI: 0.09-0.85; p = 0.025), especially with MLLV (aOR = 0.19; 95% CI: 0.04-0.97; p = 0.046) is significantly associated with hindered fibrosis regression. Our study suggests that patients with detectable serum HBV DNA levels higher than 50 IU/mL need to be monitored carefully, especially in those with more than once. Trial Registration: ClinicalTrials.gov identifiers NCT01938781 and NCT01938820.

5.
Am J Hematol ; 99(4): 633-641, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37772366

RESUMO

Herpes zoster (HZ) refers to the rash appearing on dermatomes due to varicella zoster virus (VZV) reactivation. The incidence of HZ is significantly higher in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients than in non-HSCT recipients. Although acyclovir prophylaxis is routinely administered to every allo-HSCT recipient for 1 year after transplantation, some individuals eventually develop late-onset HZ after completing prophylaxis. Little information is known about the clinical features of HZ after prophylactic antiviral treatment discontinuation, and an effective predictive model of late-onset HZ needs to be established. A total of 3366 patients who had received allo-HSCT from 2012 to 2017 were included in our study, among whom 201 developed HZ after 1 year (late-onset HZ). We designed a nested case-control study to identify potential predictors of late-onset HZ. Finally, we established a predictive model using binary logistic regression analysis. Age (p < .001), use of immunosuppressants at +1 year (p < .001), CD4-CD8 ratio at +1 year (p < .001), certain mental disorders (depression, anxiety, insomnia and adjustment disorder) (p < .001), engraftment time of neutrophils (p < .001), and CD8+ cell count at +30 days (p < .001) were independent predictors of late-onset HZ. A risk grading system was established based on regression coefficients. Discrimination and calibration analysis indicated that the model had good performance. We also identified several predictive factors of the incidence of HZ-related complications. This is the first scoring system for predicting the incidence of late-onset HZ after allo-HSCT. This model can be applied to identify individuals at high risk of late-onset HZ in the early period after receiving allo-HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Herpes Zoster , Humanos , Herpesvirus Humano 3 , Antivirais/uso terapêutico , Estudos de Casos e Controles , Transplante Homólogo/efeitos adversos , Herpes Zoster/epidemiologia , Herpes Zoster/etiologia , Herpes Zoster/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Estudos Retrospectivos
6.
J Environ Manage ; 370: 122390, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39243647

RESUMO

The establishment of S-scheme heterojunctions represents an effective strategy for enhancing the transfer and separation of charge carriers, thereby bolstering redox capacities and consequently benefiting subsequent photocatalytic reactions. In this study, the pristine Bi7O9I3 underwent a facile vulcanization process to in-situ produce various composites. Systematical characterizations confirmed the simultaneous generation of Bi7O9I3/Bi2S3 (BI-BS) heterojunctions with surface oxygen vacancies (OVs). Under visible light, these BI-BS composites exhibited improved NO removal efficiencies with reduced NO2 generation compared to bare Bi7O9I3. Particularly, the best candidate BI-BS2 possesses the highest NO removal (43.02%) and lowest NO2 generation (5.44%) among all tested samples. The improvement was primarily attributed to synergetic effects of heterojunction and surface OVs, including enhanced charge separation, heightened light responsiveness, and improved generation of reactive oxygen-containing species through an S-scheme mode. Furthermore, the Density Functional Theory (DFT) calculations had demonstrated that the establishment of BI-BS heterojunctions with surface OVs not only optimized the electronic structure to facilitate the transfer and separation of charge carriers, but also significantly enhanced the adsorption of NO, H2O, and O2 molecules, ultimately favoring the generation of NO3- species. These as-synthesized composites indicated sufficient structural stability and hold potential for the photocatalytic removal of NO at ppb levels.

7.
Wei Sheng Yan Jiu ; 53(2): 223-228, 2024 Mar.
Artigo em Zh | MEDLINE | ID: mdl-38604957

RESUMO

OBJECTIVE: To evaluate the dietary quality of the rural elderly aged 65 years and above. METHODS: In February-March 2023, a convenience sampling method was adopted to select 454 rural elderly aged 65 years and above in a township of Luzhou City. The dietary survey was conducted using a semi-quantitative food frequency questionnaire(FFQ-25), and the questionnaire information was collected by face-to-face interviews. Dietary quality was evaluated using the Dietary Balance Index-16(DBI-16) score. RESULTS: The proportion of older people in the region with moderate and high dietary imbalances was 79.7%. Inadequate and excessive dietary intake coexisted. The average daily intake of cereals and potatoes and livestock and meat foods were 356.7 g and 76.2 g, exceeding the recommended intake. The average daily intake of fruit, milk and fish and shrimp intake was 22.8 g, 36 g and 3.7 g, respectively, which was only 10% of the recommended amount, and the intake was seriously insufficient. In addition, the degree of food diversity is relatively low, with most of the average daily intake of food types ranging from five to eight, and only 4.6% of the elderly having more than eight. A total of seven dietary patterns were found among the rural elderly in the region, including a certain degree of under-consumption pattern, a severe under-consumption pattern, a certain degree of over-consumption pattern, and a pattern of both under-consumption and over-consumption. That was dominated by the pattern of severe underconsumption and the pattern of some degree of underconsumption and higher degree of overconsumption, which accounted for 72.3% of the total. CONCLUSION: The rural elderly aged 65 years and above in Luzhou City have a serious dietary imbalance, with a high proportion of insufficient intake of vegetables, fruits and milk, as well as aquatic products and eggs; and excessive intake of livestock, poultry, meat and cereals and potatoes.


Assuntos
Dieta , Verduras , Idoso , Animais , Humanos , Frutas , Cidades , Carne , China , Comportamento Alimentar
8.
Angew Chem Int Ed Engl ; 63(24): e202401943, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38594205

RESUMO

Electrochemical C-N coupling reaction based on carbon dioxide and nitrate have been emerged as a new "green synthetic strategy" for the synthesis of urea, but the catalytic efficiency is seriously restricted by the inherent scaling relations of adsorption energies of the active sites, the improvement of catalytic activity is frequently accompanied by the decrease in selectivity. Herein, a doping engineering strategy was proposed to break the scaling relationship of intermediate binding and minimize the kinetic barrier of C-N coupling. A thus designed SrCo0.39Ru0.61O3-δ catalyst achieves a urea yield rate of 1522 µg h-1 mgcat. -1 and faradic efficiency of 34.1 % at -0.7 V versus reversible hydrogen electrode. A series of characterizations revealed that Co doping not only induces lattice distortion but also creates rich oxygen vacancies (OV) in the SrRuO3. The oxygen vacancies weaken the adsorption of *CO and *NH2 intermediates on the Co and Ru sites respectively, and the strain effects over the Co-Ru dual sites promoting the occurrence of C-N coupling of the two monomers instead of selective hydrogenating to form by-products. This work presents an insight into molecular coupling reactions towards urea synthesis via the doping engineering on SrRuO3.

9.
Br J Haematol ; 200(6): 759-768, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36464324

RESUMO

Prolonged isolated thrombocytopenia (PT) is a life-threatening comorbidity associated with allogeneic haematopoietic stem cell transplantation (allo-HSCT). Our previous study indicated that dysfunctional bone marrow mesenchymal stromal cells (BM MSCs) played a role in PT pathogenesis and that reactive oxygen species (ROS) accumulation was related to BM MSC senescence and apoptosis. However, the mechanism of the increase in ROS levels in the BM MSCs of PT patients is unknown. In the current case-control study, we investigated whether nuclear factor erythroid 2-related factor 2 (NRF2), which is a central regulator of the cellular anti-oxidant response that can clear ROS in human BM MSCs, was associated with PT after allo-HSCT. We evaluated whether an NRF2 agonist (tert-butylhydroquinone, TBHQ) could enhance BM MSCs from PT patients in vitro. We found that BM MSCs from PT patients exhibited increased ROS levels and reduced NRF2 expression. Multivariate analysis showed that low NRF2 expression was an independent risk factor for primary PT [p = 0.032, Odds ratio (OR) 0.868, 95% confidence interval (CI) 0.764-0.988]. In-vitro treatment with TBHQ improved the quantity and function of BM MSCs from PT patients by downregulating ROS levels and rescued the impaired BM MSC support of megakaryocytopoiesis. In conclusion, these results suggested that NRF2 downregulation in human BM MSCs might be involved in the pathogenesis of PT after allo-HSCT and that BM MSC impairment could be improved by NRF2 agonist in vitro. Although further validation is needed, our data indicate that NRF2 agonists might be a potential therapeutic approach for PT patients after allo-HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Trombocitopenia , Humanos , Medula Óssea/patologia , Estudos de Casos e Controles , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transplante Homólogo/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Células da Medula Óssea/patologia , Trombocitopenia/etiologia , Células-Tronco Mesenquimais/metabolismo , Transplante de Células-Tronco Mesenquimais/efeitos adversos
10.
Small ; 19(15): e2206865, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36634977

RESUMO

Defect engineering for vacancies, holes, nano precipitates, dislocations, and strain are efficient means of suppressing lattice thermal conductivity. Multiple microstructural defects are successfully designed in Cu1- x Agx GaTe2 (0 ≤ x ≤ 0.5) solid solutions through high-ratio alloying and vibratory ball milling, to achieve ultra-low thermal conductivity and record-breaking thermoelectric performance. Extremely low total thermal conductivities of 1.28 W m-1  K-1 at 300 K and 0.40 W m-1  K-1 at 873 K for the Cu0.5 Ag0.5 GaTe2 are observed, which are ≈79% and ≈58% lower than that of the CuGaTe2 matrix. Multiple phonon scattering mechanisms are collectively responsible for the reduction of thermal conductivity in this work. On one hand, large amounts of nano precipitates and dislocations are formed via vibrating ball milling followed by the low-temperature hot press, which can enhance phonon scattering. On the other hand, the difference in atomic sizes, distorted chemical bonds, elements fluctuation, and strained domains are caused by the high substitution ratio of Ag and also function as a center for the strong phonon scattering. As a result, the Cu0.7 Ag0.3 GaTe2 exhibits a record high ZTmax of ≈1.73 at 873 K and ZTave of ≈0.69 between 300-873 K, which are the highest values of CuGaTe2 -based thermoelectric materials.

11.
Nano Lett ; 22(8): 3503-3511, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35315671

RESUMO

Metal ion substitution and anion exchange are two effective strategies for regulating the electronic and geometric structure of spinel. However, the optimal location of foreign metallic cations and the exact role of these metals and anions remain elusive. Herein, CoFe2O4-based hollow nanospheres with outstanding oxygen evolution reaction activity are prepared by Cr3+ substitution and S2- exchange. X-ray absorption spectra and theoretical calculations reveal that Cr3+ can be precisely doped into octahedral (Oh) Fe sites and simultaneously induce Co vacancy, which can activate adjacent tetrahedral (Td) Fe3+. Furthermore, S2- exchange results in structure distortion of Td-Fe due to compressive strain effect. The change in the local geometry of Td-Fe causes the *OOH intermediate to deviate from the y-axis plane, thus enhancing the adsorption of the *OOH. The Co vacancy and S2- exchange can adjust the geometric and electronic structure of Td-Fe, thus activating the inert Td-Fe and improving the electrochemical performance.


Assuntos
Metais , Oxigênio , Catálise , Cátions/química , Metais/química , Oxigênio/química
12.
Angew Chem Int Ed Engl ; 62(10): e202217275, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36629025

RESUMO

Alkaline fuel cells can permit the adoption of platinum group metal-free (PGM-free) catalysts and cheap bipolar plates, thus further lowering the cost. With the exploration of PGM-free hydrogen oxidation reaction (HOR) catalysts, nickel-based compounds have been considered as the most promising HOR catalysts in alkali. Here we report an interfacial engineering through the formation of nickel-vanadium oxide (Ni/V2 O3 ) heterostructures to activate Ni for efficient HOR catalysis in alkali. The strong electron transfer from Ni to V2 O3 could modulate the electronic structure of Ni sites. The optimal Ni/V2 O3 catalyst exhibits a high intrinsic activity of 0.038 mA cm-2 and outstanding stability. Experimental and theoretical studies reveal that Ni/V2 O3 interface as the active sites can enable to optimize the hydrogen and hydroxyl bindings, as well as protect metallic Ni from extensive oxidation, thus achieving the notable activity and durability.

13.
J Am Chem Soc ; 144(29): 13163-13173, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35849786

RESUMO

Hydrogen production from water electrolysis in neutral-pH electrolytes can not only avoid the corrosion and safety issues and expand the catalyst option but also potentially integrate with artificial photosynthesis and bioelectrocatalysis. However, heterogeneous catalysts that can efficiently negotiate the sluggish oxygen evolution reaction (OER) in neutral solutions are considerably lacking. Herein, we report a template-assisted strategy for the synthesis of 13 kinds of tube-like nanostructured perovskite oxides (TNPOs) with markedly high Brunauer-Emmett-Teller surface areas. By systematic examination of these TNPOs, we found that the OER activity of TNPOs in neutral solution exhibits a volcano shape as a function of the covalency of transition metal-oxygen bonds. Consequently, our designed Sm-doped LaCoO3 catalyst yields a geometric current density of 8.5 mA cm-2 at 1.75 V versus the reversible hydrogen electrode in 1 M phosphate buffer solution (pH 7) due to the optimized covalency of Co 3d and O 2p states, representing the most active noble-metal-free OER catalyst in neutral electrolytes reported as yet.


Assuntos
Elementos de Transição , Água , Compostos de Cálcio , Hidrogênio , Óxidos , Oxigênio/química , Titânio
14.
J Am Chem Soc ; 144(21): 9271-9279, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35549330

RESUMO

The two-dimensional surface or one-dimensional interface of heterogeneous catalysts is essential to determine the adsorption strengths and configurations of the reaction intermediates for desired activities. Recently, the development of single-atom catalysts has enabled an atomic-level understanding of catalytic processes. However, it remains obscure whether the conventional concept and mechanism of one-dimensional interface are applicable to zero-dimensional single atoms. In this work, we arranged the locations of single atoms to explore their interfacial interactions for improved oxygen evolution. When iridium single atoms were confined into the lattice of CoOOH, efficient electron transfer between Ir and Co tuned the adsorption strength of oxygenated intermediates. In contrast, atomic iridium species anchored on the surface of CoOOH induced inappreciable modification in electronic structures, whereas steric interactions with key intermediates at its Ir-OH-Co interface played a primary role in reducing its energy barrier toward oxygen evolution.

15.
BMC Med ; 20(1): 140, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35473809

RESUMO

BACKGROUND: Poor graft function (PGF) or prolonged isolated thrombocytopenia (PT), which are characterized by pancytopenia or thrombocytopenia, have become serious complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Our previous single-arm trial suggests that N-acetyl-L-cysteine (NAC) prophylaxis reduced PGF or PT after allo-HSCT. Therefore, an open-label, randomized, phase 3 trial was performed to investigate the efficacy and tolerability of NAC prophylaxis to reduce PGF or PT after allo-HSCT. METHODS: A phase 3, open-label randomized trial was performed. Based on the percentage of CD34+VEGFR2 (CD309)+ endothelial cells (ECs) in bone marrow (BM) detected by flow cytometry at 14 days before conditioning, patients aged 15 to 60 years with acute leukemia undergoing haploidentical HSCT were categorized as low-risk (EC ≥ 0.1%) or high-risk (EC < 0.1%); patients at high risk were randomly assigned (2:1) to receive NAC prophylaxis or nonprophylaxis. The primary endpoint was PGF and PT incidence at +60 days post-HSCT. RESULTS: Between April 18, 2019, and June 24, 2021, 120 patients with BM EC <0.1% were randomly assigned for NAC (group A, N = 80) or nonprophylaxis (group B, N = 40), and 105 patients with EC≥0.1% (group C) were also analyzed. The +60 days incidence of PGF and PT was 7.5% (95% CI, 1.7 to 13.3%) and 22.5% (95% CI, 9.1 to 35.9%) in group A and group B (hazard ratio, 0.317; 95% CI, 0.113 to 0.890; P = 0.021) and 11.4% (95% CI, 5.2 to 17.6%) in group C (hazard ratio, 0.643; 95% CI, 0.242 to 1.715; P = 0.373). Consistently, NAC prophylaxis gradually improved BM ECs and CD34+ cells in group A, whereas reduced their reactive oxygen species (ROS) levels post-HSCT. Within 60 days post-HSCT, the most common grade 3 to 5 adverse events for the NAC and control groups were infections (19/80 [24%] vs. 10/40 [25%]) and gastrointestinal adverse events (16/80 [20%] vs. 7/40 [18%]). There were no treatment-related deaths. CONCLUSIONS: N-Acetyl-L-cysteine prophylaxis can prevent the occurrence of poor hematopoietic function and is well tolerated in haploidentical HSCT. It may offer a potential pathogenesis-oriented therapeutic approach for patients with poor hematopoietic function. TRIAL REGISTRATION: This trial was registered at ClinicalTrials.gov as #NCT03967665.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Trombocitopenia , Humanos , Acetilcisteína/uso terapêutico , Células Endoteliais , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Trombocitopenia/etiologia
16.
J Transl Med ; 20(1): 144, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35351133

RESUMO

BACKGROUND: Myelodysplastic syndromes (MDS) are a group of heterogeneous myeloid clonal disorders characterized by ineffective haematopoiesis and immune deregulation. Emerging evidence has shown the effect of bone marrow (BM) endothelial progenitor cells (EPCs) in regulating haematopoiesis and immune balance. However, the number and functions of BM EPCs in patients with different stages of MDS remain largely unknown. METHODS: Patients with MDS (N = 30), de novo acute myeloid leukaemia (AML) (N = 15), and healthy donors (HDs) (N = 15) were enrolled. MDS patients were divided into lower-risk MDS (N = 15) and higher-risk MDS (N = 15) groups according to the dichotomization of the Revised International Prognostic Scoring System. Flow cytometry was performed to analyse the number of BM EPCs. Tube formation and migration assays were performed to evaluate the functions of BM EPCs. In order to assess the gene expression profiles of BM EPCs, RNA sequencing (RNA-seq) were performed. BM EPC supporting abilities of haematopoietic stem cells (HSCs), leukaemia cells and T cells were assessed by in vitro coculture experiments. RESULTS: Increased but dysfunctional BM EPCs were found in MDS patients compared with HDs, especially in patients with higher-risk MDS. RNA-seq indicated the progressive change and differences of haematopoiesis- and immune-related pathways and genes in MDS BM EPCs. In vitro coculture experiments verified that BM EPCs from HDs, lower-risk MDS, and higher-risk MDS to AML exhibited a progressively decreased ability to support HSCs, manifested as elevated apoptosis rates and intracellular reactive oxygen species (ROS) levels and decreased colony-forming unit plating efficiencies of HSCs. Moreover, BM EPCs from higher-risk MDS patients demonstrated an increased ability to support leukaemia cells, characterized by increased proliferation, leukaemia colony-forming unit plating efficiencies, decreased apoptosis rates and apoptosis-related genes. Furthermore, BM EPCs induced T cell differentiation towards more immune-tolerant cells in higher-risk MDS patients in vitro. In addition, the levels of intracellular ROS and the apoptosis ratios were increased in BM EPCs from MDS patients, especially in higher-risk MDS patients, which may be therapeutic candidates for MDS patients. CONCLUSION: Our results suggest that dysfunctional BM EPCs are involved in MDS patients, which indicates that improving haematopoiesis supporting ability and immuneregulation ability of BM EPCs may represent a promising therapeutic approach for MDS patients.


Assuntos
Células Progenitoras Endoteliais , Síndromes Mielodisplásicas , Apoptose , Medula Óssea , Células-Tronco Hematopoéticas , Humanos , Síndromes Mielodisplásicas/genética
17.
Haematologica ; 107(10): 2365-2380, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35354250

RESUMO

Bone marrow (BM) endothelial progenitor cell (EPC) damage of unknown mechanism delays the repair of endothelial cells (EC) and recovery of hematopoiesis after chemo-radiotherapy. We found increased levels of the glycolytic enzyme PFKFB3 in the damaged BM EPC of patients with poor graft function, a clinical model of EPC damage-associated poor hematopoiesis after allogeneic hematopoietic stem cell transplantation. Moreover, in vitro the glycolysis inhibitor 3-(3-pyridinyl)- 1-(4-pyridinyl)-2-propen-1-one (3PO) alleviated the damaged BM EPC from patients with poor graft function. Consistently, PFKFB3 overexpression triggered BM EPC damage after 5-fluorouracil treatment and impaired hematopoiesis-supporting ability in vitro. Mechanistically, PFKFB3 facilitated pro-apoptotic transcription factor FOXO3A and expression of its downstream genes, including p21, p27, and FAS, after 5-fluorouracil treatment in vitro. Moreover, PFKFB3 induced activation of NF-κB and expression of its downstream adhesion molecule E-selectin, while it reduced hematopoietic factor SDF-1 expression, which could be rescued by FOXO3A silencing. High expression of PFKFB3 was found in damaged BM EC of murine models of chemo-radiotherapy-induced myelosuppression. Furthermore, a murine model of BM EC-specific PFKFB3 overexpression demonstrated that PFKFB3 aggravated BM EC damage, and impaired the recovery of hematopoiesis after chemotherapy in vivo, effects which could be mitigated by 3PO, indicating a critical role of PFKFB3 in regulating BM EC damage. Clinically, PFKFB3-induced FOXO3A expression and NF-κB activation were confirmed to contribute to the damaged BM EPC of patients with acute leukemia after chemotherapy. 3PO repaired the damaged BM EPC by reducing FOXO3A expression and phospho-NF-κB p65 in patients after chemotherapy. In summary, our results reveal a critical role of PFKFB3 in triggering BM EPC damage and indicate that endothelial-PFKFB3 may be a potential therapeutic target for myelosuppressive injury.


Assuntos
Células Progenitoras Endoteliais , NF-kappa B , Animais , Humanos , Camundongos , Medula Óssea/metabolismo , Selectina E/metabolismo , Células Progenitoras Endoteliais/metabolismo , Fluoruracila/farmacologia , Glicólise , NF-kappa B/metabolismo , Fosfofrutoquinase-2/genética , Fosfofrutoquinase-2/metabolismo
18.
BMC Cancer ; 22(1): 1043, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36199039

RESUMO

BACKGROUND: Rectal cancer is one of the most lethal of gastrointestinal malignancies. Metabonomics has gradually developed as a convenient, inexpensive and non-destructive technique for the study of cancers. METHODS: A total of 150 tissue samples from 25 rectal cancer patients were analyzed by liquid chromatography-mass spectrometry (LC-MS), and 6 tissue samples were collected from each patient (group 1: tumor; group 2: 0.5 cm from tumor; group 3:1 cm from tumor; group 4:2 cm from tumor; group 5:3 cm from tumor and group 6:5 cm from tumor). The differential metabolites of tumor tissues and 5 cm from the tumor (normal tissues) were first selected. The differential metabolites between tumor tissues and normal tissues were regrouped by hierarchical clustering analysis, and further selected by discriminant analysis according to the regrouping of clustering results. The potential safe margin of clinical T(cT)1,cT2 stage rectal cancer and cT3,cT4 stage rectal cancer at the metabolomic level was further identified by observing the changes in the level of differential metabolites within the samples from group 1 to group 6. RESULTS: We found 22 specific metabolites to distinguish tumor tissue and normal tissue. The most significant changes in metabolite levels were observed at 0.5 cm (cT1, cT2) and 2.0 cm (cT3, cT4) from the tumor, while the changes in the tissues afterwards showed a stable trend. CONCLUSIONS: There are differential metabolites between tumor tissues and normal tissues in rectal cancer. Based on our limited sample size, the safe distal incision margin for rectal cancer surgery in metabolites may be 0.5 cm in patients with cT1 and cT2 stage rectal cancer and 2.0 cm in patients with cT3 and cT4 stage rectal cancer.


Assuntos
Neoplasias Retais , Humanos , Margens de Excisão , Metabolômica , Neoplasias Retais/patologia , Reto/patologia
19.
Bioorg Chem ; 121: 105665, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35152138

RESUMO

Berberine is a quaternary isoquinoline alkaloid that exhibits potent hypoglycemic and hypolipidemic activity. Many medicinal chemists are currently working on structural modifications around the parent scaffold of berberine, expecting to further enhance its hypolipidemic activity and reducing its cytotoxicity. In this study, a focused berberine-like compound library containing 12,600 molecules was built via the introduction of various "drug-like" fragments at the C8 and C9 positions of berberine. Sixteen comopounds were hit by using the in-house QSAR models previously reported by our group. Considering synthesis feasibility and the cost of building-blocks, only four berberine analogs (library ID: 2028, 3847, 6033, and 12456) were selected and synthesized for investigating their lipid-lowering activities. Preliminary lipid-lowering study showed that compound 12456 with the phenylsulfonyl group at the C9 position had potent cholesterol inhibitory activity in HepG2 cells, superior to that of the parent compound berberine. Subsequently, a total of twenty-five 9-O-phenylsulfonyl-berberines (1a-1y) and twenty-four 9-O-phenylsulfonyl-tetrahydroberberine (2a-2x) were designed, synthesized, and evaluated by lipid-lowering experiments. The results displayed that most compounds exhibited more lipid-lowering activities than berberine. Among them, compound 1m inhibited cholesterol production close to 50% in both cell models when compared with the blank control; the inhibition of triglycerides exceeded 70%. Moreover, 1m also had significant pharmacological effects on the inhibition of LDLC and promotion of HDLC production, especially in the HepG2 cell model, in which the inhibitory rate against LDLC was close to 70% and the increase rate of HDLC was more than 75%. The hypolipidemic experiment of SD rats demonstrated that after 40 days of administration (1m, 15 mg/kg/d), blood cholesterol was reduced by 19.6%, triglycerides reduced by 34.52%, and LDLC reduced by 41.49%, when compared with the high-fat diet model (HFD). In addition, after 80 days of administration, the three indexes of 1m were still better than that of berberine. Oil Red O staining and H&E staining results showed that 1m exhibited potent lipid scavenging activity. All in all, 1m was discovered and identified as a potent lipid-lowering agent and a new berberine-like candidate, being evaluated by subsequent studies.


Assuntos
Berberina , Animais , Berberina/química , Berberina/farmacologia , Colesterol , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Ratos , Ratos Sprague-Dawley , Triglicerídeos
20.
Ecotoxicol Environ Saf ; 230: 113151, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34990992

RESUMO

Ultrasonic technology is an environment-friendly method in algae-laden water treatment with the advantages of wonderful efficiency and no chemical additions. However, ultrasonic technology is costly and can lead to the release of algae organic matter (AOM). Few studies considered algae removal efficiency, water safety, and economy. In this study, a Response Surface Methodology (RSM) and Elitist Non-dominated Sorting Genetic Algorithm (NSGA-II) integrated method was used to investigate the influence of ultrasound parameters on algal removal efficiency band AOM release and conduct the multi-objective optimization of ultrasonic technology for satisfactory algal removal, environment protection, and improved economy. The maximum algae removal rate (ρ), minimal energy consumption, and minimal UV254 value of algal solution were calculated. Quadratic polynomial models were obtained to illustrate the relationship between ultrasonic parameters and the responses. Ultrasonic frequency was the most important factor affecting algal removal efficiency, and high frequency was beneficial for algal removal because of its contribution to the break of air bubbles. High power density significantly increased the UV254 value, and the concentration of soluble microbial metabolites and humic acid-like substances significantly increased after ultrasound. The optimization solutions calculated by NSGA-II showed low deviation from single-objective optimization solution by RSM, demonstrating that the multi-objective optimization results were reliable. This study presents a novel RSM and NSGA-II combined method in optimizing ultrasonic technology for effective, safe, and economic algal removal. The optimization results can provide references for ultrasonic parameters to be selected in practical applications.

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