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1.
J Phys Chem Lett ; : 4792-4798, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38666719

RESUMO

Sn-doped lead halide perovskites (LHPs) have attracted considerable attention for their lower bandgap and lower toxicity. While it is well-established that Sn doping easily introduces a lot of structural defects into LHP films, the extent to which these defects impact carrier dynamics has yet to be fully elucidated. Herein, we take Sn-doped MAPbBr3 films as an example to explore the influence of Sn doping on their carrier dynamics. The results show that Sn doping can simultaneously introduce many fillable electron traps and unfillable hole traps, consequently instigating an ultrafast carrier capture process. This further elicits long-lived internal charge separation between band edge and trap states or between two kinds of trap states, thereby enabling these carriers to persist for up to ∼2.6 µs. Our findings suggest that Sn doping potentially serves as an effective strategy to prolong the carrier lifetime in LHPs, which could pave the way for potential applications within Sn-based perovskites.

2.
Clin Breast Cancer ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38641470

RESUMO

OBJECTIVE: The association of FGFR2-rs13387042 polymorphism with breast cancer (BC) susceptibility in women remains inconclusive due to varying reports. In this study, we conducted a meta-analysis to explore the relationship between FGFR2-rs13387042 polymorphism and susceptibility to BC. METHODS: Relevant literature were acquired through searches across multiple databases. Odds ratio (OR) values were pooled to assess the risk of BC for different alleles and genotypes. The heterogeneity among the included literature was evaluated. Sensitivity analysis was used to verify the stability of the results. Egger's linear regression test was used to assess the significance of publication bias of the included literature. RESULTS: A total of 17 publications were included, encompassing 122,607 cases and 175,966 controls. There was significantly increased risk of BC for allele A compared with G (OR = 1.15, 95% CI = 1.14-1.67, P < .001), genotype AA compared with GG (OR = 1.34, 95% CI = 1.29-1.38, P < .001), and genotype GA compared with GG (OR = 1.19, 95% CI = 1.12-1.26, P < .001). Both Egger's test and funnel plot indicated the presence of publication bias. After adjusting potential publication bias by the trim-and-fill method, the comparison of allele A versus G (OR = 1.15, 95% CI = 1.13-1.17, P < .001), genotype AA versus GG (OR = 1.32, 95% CI = 1.28-1.37, P < .001), and genotype GA versus GG (OR = 1.15, 95% CI = 1.09-1.22, P < .001) remained statistically significant. In various subgroups, the allele A showed significantly higher risk of BC upon allele G in estrogen receptor (ER) positive BC, ER negative BC, progesterone receptor (PR) positive BC, PR negative BC, triple-negative BC, pathological grade I BC, grade II BC, and grade III breast cancer. The subsequent sensitivity analysis suggested the above findings stable and reliable. CONCLUSION: In this study, we found that the allele A of the FGFR2-rs13387042 polymorphism is associated with increased risk of developing breast cancer. This study underscores its potential as a genetic marker for personalized risk assessment and targeted interventions.

3.
Clin Lab ; 70(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38623678

RESUMO

BACKGROUND: The goal was to develop a risk assessment model for predicting red blood cell (RBC) transfusion in neonatal patients to assist hospital blood supply departments in providing small portions of RBCs to those requiring RBC transfusion on time. METHODS: Clinical information was collected from 1,201 children admitted to the neonatal unit. Clinical factors associated with predicting RBC transfusion were screened, and prediction models were developed using stepwise and multifactorial logistic regression analyses, followed by the evaluation of prediction models using receiver operating characteristic curves, calibration curves, and decision curve analysis (DCA). RESULTS: Overall, 81 neonatal patients were transfused with RBCs, and the variables of gestational age at birth, age < 1 month, receipt of mechanical ventilation, and infant anemia were included in the final prediction model. The area under the curve of the prediction model was 0.936 (0.921 - 0.949), which was significantly higher than that of the individual indicators of gestational age at birth, age at admission < 1 month, receipt of mechanical ventilation, and infant anemia (p < 0.001). DCA showed a standardized net benefit for the possible risk of infant RBC transfusion at 0.1 - 1.0. CONCLUSIONS: We developed a risk assessment model to predict the risk of RBC transfusion in neonatal patients that can effectively assess the risk of RBC transfusion in children.


Assuntos
Anemia , Transfusão de Eritrócitos , Recém-Nascido , Lactente , Criança , Humanos , Transfusão de Eritrócitos/efeitos adversos , Anemia/diagnóstico , Anemia/terapia , Idade Gestacional , Eritrócitos , Medição de Risco
4.
Adv Mater ; : e2401018, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602072

RESUMO

It remains a significant challenge to construct active sites to break the trade-off between oxidation and reduction processes occurring in battery cathodes with conversion mechanism, especially for the oxygen reduction and evolution reactions (ORR/OER) involved in the zinc-air batteries (ZABs). Here, using a high-entropy-driven electric dipole transition strategy to activate and stabilize the tetrahedral sites is proposed, while enhancing the activity of octahedral sites through orbital hybridization in a FeCoNiMnCrO spinel oxide, thus constructing bipolar dual-active sites with high-low valence states, which can effectively decouple ORR/OER. The FeCoNiMnCrO high-entropy spinel oxide with severe lattice distortion, exhibits a strong 1s→4s electric dipole transition and intense t2g(Co)/eg(Ni)-2p(OL) orbital hybridization that regulates the electronic descriptors, eg and t2g, which leads to the formation of low-valence Co tetrahedral sites (Coth) and high-valence Ni octahedral sites (Nioh), resulting in a higher half-wave potential of 0.87 V on Coth sites and a lower overpotential of 0.26 V at 10 mA cm-2 on Nioh sites as well as a superior performance of ZABs compared to low/mild entropy spinel oxides. Therefore, entropy engineering presents a distinctive approach for designing catalytic sites by inducing novel electromagnetic properties in materials across various electrocatalytic reactions, particularly for decoupling systems.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38569189

RESUMO

BACKGROUND: The metabolic score for insulin resistance (METS-IR) has emerged as a noninsulin-based index for the approximation of IR, yet longitudinal evidence supporting the utility of METS-IR in primary prevention of type 2 diabetes mellitus (T2DM) remains limited. OBJECTIVE: We aimed to investigate the longitudinal association between METS-IR, which combines fasting plasma glucose (FPG), lipid profiles and anthropometrics that can be routinely obtained in resource-limited primary care settings, and incidence of new-onset T2DM. METHODS: We conducted a closed-cohort analysis of a nationwide, prospective cohort of 7,583 Chinese middle-aged and older adults who were free of T2DM at baseline, sampled from 28 out of 31 provinces in China. We examined the characteristics of subjects stratified by elevated blood pressure (BP) at baseline and new-onset T2DM at follow-up. We performed Cox proportional hazard regression analysis to explore associations of baseline METS-IR with incident T2DM in subjects overall, and in subjects stratified by baseline BP. We also applied net reclassification improvement (NRI) and integrated discrimination improvement (IDI) to examine the incremental value of METS-IR. RESULTS: During a mean follow-up period of 6.3 years, T2DM occurred in 527 subjects, among which, two-thirds (63.0%, 95% confidence interval [CI]: 58.7% to 67.1%) had baseline FPG <110 mg/dL. A standard deviation unit increase in baseline METS-IR was associated with the first incidence of T2DM (adjusted hazard ratio [aHR]=1.33, 1.22 to 1.45, P<.001) in all participants. Similar results were obtained in subjects with normal baseline BP (aHR=1.41, 1.22 to 1.62, P<.001) and elevated baseline BP (aHR=1.29, 1.16 to 1.44, P<.001). The predictive capability for incident T2DM improved by adding METS-IR to FPG. In study subjects with new-onset T2DM whose baseline FPG <126 mg/dL and <110 mg/dL, 63.0% (95%CI, 60.0% to 65.9%) and 58.1% (95%CI, 54.3% to 61.9%) of subjects had baseline METS-IR above the cut-off values, respectively. CONCLUSIONS: METS-IR was significantly associated with new-onset T2DM regardless of baseline BP level. Regular monitoring of METS-IR on top of routine blood glucose in clinical practice may add to the ability to enhance the early identification of primary care population at risk for T2DM.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38572719

RESUMO

PURPOSE: This study was designed to conduct pooled comparisons of the relative clinical efficacy and safety of computed tomography (CT)-guided localization for pulmonary nodules (PNs) using either coil- or liquid material-based approaches. MATERIAL AND METHODS: Relevant articles published as of July 2023 were identified in the Web of Science, PubMed, and Wanfang databases, and pooled analyses of relevant endpoints were then conducted. RESULTS: Six articles that enrolled 287 patients (341 PNs) and 247 patients (301 PNs) that had respectively undergone CT-guided localization procedures using coil- and liquid material-based approaches prior to video-assisted thoracic surgery (VATS) were included in this meta-analysis. The liquid material group exhibited a significantly higher pooled successful localization rate as compared to the coil group (p = 0.01), together with significantly lower pooled total complication rates (p = 0.0008) and pneumothorax rates (p = 0.01). Both groups exhibited similar rates of pulmonary hemorrhage (p = 0.44) and successful wedge resection (p = 0.26). Liquid-based localization was also associated with significant reductions in pooled localization and VATS procedure durations (p = 0.004 and 0.007). CONCLUSIONS: These data are consistent with CT-guided localization procedures performed using liquid materials being safer and more efficacious than coil-based localization in patients with PNs prior to VATS resection.

7.
iScience ; 27(4): 109469, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38577101

RESUMO

The extracellular superoxide dismutases (ecSODs) secreted by Microplitis bicoloratus reduce the reactive oxygen species (ROS) stimulated by the Microplitis bicoloratus bracovirus. Here, we demonstrate that the bacterial transferase hexapeptide (hexapep) motif and bacterial-immunoglobulin-like (BIg-like) domain of ecSODs bind to the cell membrane and transiently open hemichannels, facilitating ROS reductions. RNAi-mediated ecSOD silencing in vivo elevated ROS in host hemocytes, impairing parasitoid larva development. In vitro, the ecSOD-monopolymer needed to be membrane bound to open hemichannels. Furthermore, the hexapep motif in the beta-sandwich of ecSOD49 and ecSOD58, and BIg-like domain in the signal peptides of ecSOD67 were required for cell membrane binding. Hexapep motif and BIg-like domain deletions induced ecSODs loss of adhesion and ROS reduction failure. The hexapep motif and BIg-like domain mediated ecSOD binding via upregulating innexins and stabilizing the opened hemichannels. Our findings reveal a mechanism through which ecSOD reduces ROS, which may aid in developing anti-redox therapy.

8.
Nat Commun ; 15(1): 2905, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575613

RESUMO

Two-dimensional materials with ultrahigh in-plane thermal conductivity are ideal for heat spreader applications but cause significant thermal contact resistance in complex interfaces, limiting their use as thermal interface materials. In this study, we present an interfacial phonon bridge strategy to reduce the thermal contact resistance of boron nitride nanosheets-based composites. By using a low-molecular-weight polymer, we are able to manipulate the alignment of boron nitride nanosheets through sequential stacking and cutting, ultimately achieving flexible thin films with a layer of arc-like structure superimposed on perpendicularly aligned ones. Our results suggest that arc-like structure can act as a phonon bridge to lower the contact resistance by 70% through reducing phonon back-reflection and enhancing phonon coupling efficiency at the boundary. The resulting composites exhibit ultralow thermal contact resistance of 0.059 in2 KW-1, demonstrating effective cooling of fast-charging batteries at a thickness 2-5 times thinner than commercial products.

9.
Toxicol Appl Pharmacol ; : 116920, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38582373

RESUMO

Asparaginase-associated pancreatitis (AAP) is a severe and potentially life-threatening drug-induced pancreas targeted toxicity in the combined chemotherapy of acute lymphoblastic leukemia among children and adolescents. The toxicological mechanism of AAP is not yet clear, and there are no effective preventive and treatment measures available clinically. Fibroblast growth factor 21 (FGF21) is a secretory hormone that regulates lipid, glucose, and energy metabolism balance. Acinar tissue is the main source of pancreatic FGF21 protein and plays an important role in maintaining pancreatic metabolic balance. In this study, we found that the decrease of FGF21 in pancreas is closely related to AAP. Pegaspargase (1 IU/g) induces widespread edema and inflammatory infiltration in the pancreas of rats/mice. The specific expression of FGF21 in the acinar tissue of AAP rats was significantly downregulated. Asparaginase caused dysregulation of the ATF4/ATF3/FGF21 axis in acinar tissue or cells, and thus mediated the decrease of FGF21. It greatly activated ATF3 in the acinar, which competed with ATF4 for the Fgf21 promoter, thereby inhibiting the expression of FGF21. Pharmacological replacement of FGF21 (1 mg/kg) or PERK inhibitors (GSK2656157, 25 mg/kg) can significantly mitigate the pancreatic tissue damage and reduce markers of inflammation associated with AAP, representing potential strategies for the prevention and treatment of AAP.

10.
Blood ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657191

RESUMO

Hematopoietic differentiation is controlled by intrinsic regulators and the extrinsic hematopoietic niche. Activating transcription factor 4 (ATF4) plays a crucial role in the function of fetal and adult hematopoietic stem cell maintenance; however, the precise function of ATF4 in the bone marrow niche and the mechanism by which ATF4 regulates adult hematopoiesis remain largely unknown. Here, we employ four cell-type-specific mouse Cre lines to achieve conditional knockout of Atf4 in Cdh5+ endothelial cells, Prx1+ bone marrow stromal cells, Osx+ osteo-progenitor cells, and Mx1+ hematopoietic cells, and uncover the role of Atf4 in niche cells and hematopoiesis. Intriguingly, depletion of Atf4 in niche cells does not affect hematopoiesis; however, Atf4-deficient hematopoietic cells exhibit erythroid differentiation defects, leading to hypoplastic anemia. Mechanistically, ATF4 mediates direct regulation of Rps19bp1 transcription, which is, in turn, involved in 40S ribosomal subunit assembly to coordinate ribosome biogenesis and promote erythropoiesis. Finally, we demonstrate that under conditions of 5-fluorouracil-induced stress, Atf4 depletion impedes the recovery of hematopoietic lineages, which requires efficient ribosome biogenesis. Taken together, our findings highlight the indispensable role of the ATF4-RPS19BP1 axis in the regulation of erythropoiesis.

11.
Nature ; 628(8007): 313-319, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38570689

RESUMO

Transition metal tellurides (TMTs) have been ideal materials for exploring exotic properties in condensed-matter physics, chemistry and materials science1-3. Although TMT nanosheets have been produced by top-down exfoliation, their scale is below the gram level and requires a long processing time, restricting their effective application from laboratory to market4-8. We report the fast and scalable synthesis of a wide variety of MTe2 (M = Nb, Mo, W, Ta, Ti) nanosheets by the solid lithiation of bulk MTe2 within 10 min and their subsequent hydrolysis within seconds. Using NbTe2 as a representative, we produced more than a hundred grams (108 g) of NbTe2 nanosheets with 3.2 nm mean thickness, 6.2 µm mean lateral size and a high yield (>80%). Several interesting quantum phenomena, such as quantum oscillations and giant magnetoresistance, were observed that are generally restricted to highly crystalline MTe2 nanosheets. The TMT nanosheets also perform well as electrocatalysts for lithium-oxygen batteries and electrodes for microsupercapacitors (MSCs). Moreover, this synthesis method is efficient for preparing alloyed telluride, selenide and sulfide nanosheets. Our work opens new opportunities for the universal and scalable synthesis of TMT nanosheets for exploring new quantum phenomena, potential applications and commercialization.

12.
Adv Mater ; : e2402580, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630978

RESUMO

Inherently immunogenic materials offer enormous prospects in enhancing vaccine efficacy. However, the understanding and improving material adjuvanticity remain elusive. Herein how the structural presentation of immunopotentiators in a material governs the dynamic dialogue between innate and adaptive immunity for enhanced cancer vaccination is reported. The immunopotentiator manganese into six differing structures that resemble the architectures of two types of pathogens (spherical viruses or rod-like bacteria) is precisely manipulated. The results reveal that innate immune cells accurately sense and respond to the architectures, of which two outperformed material candidates (151 nm hollow spheres and hollow microrods with an aspect ratio of 4.5) show higher competence in creating local proinflammatory environment with promoted innate immune cell influx and stimulation on dendritic cells (DCs). In combination with viral peptides, model proteins, or cell lysate antigens, the outperformed microrod material remarkably primes antigen-specific CD8 cytolytic T cells. In prophylactic and therapeutic regimens, the microrod adjuvanted vaccines display optimal aptitude in tumor suppression in four aggressive murine tumor models, by promoting the infiltration of heterogeneous cytolytic effector cells while decreasing suppressive immunoregulatory populations in tumors. This study demonstrates that a rationally selected architecture of immunogenic materials potentially advances the clinical reality of cancer vaccination.

13.
Small ; : e2401146, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38618939

RESUMO

Lithium-carbon dioxide (Li-CO2) batteries offer the possibility of synchronous implementation of carbon neutrality and the development of advanced energy storage devices. The exploration of low-cost and efficient cathode catalysts is key to the improvement of Li-CO2 batteries. Herein, high-entropy alloys (HEAs)@C hierarchical nanosheet is synthesized from the simulation of the recycling solution of waste batteries to construct a cathode for the first time. Owing to the excellent electrical conductivity of the carbon material, the unique high-entropy effect of the HEAs, and the large number of catalytically active sites exposed by the hierarchical structure, the FeCoNiMnCuAl@C-based battery exhibits a superior discharge capability of 27664 mAh g-1 and outstanding durability of 134 cycles as well as low overpotential with 1.05 V at a discharge/recharge rate of 100 mA g-1. The adsorption capacity of different sites on the HEAs is deeply understood through density functional theory calculations combined with experiments. This work opens up the application of HEAs in Li-CO2 batteries catalytic cathodes and provides unique insights into the study of adsorption active sites in HEAs.

14.
Int J Colorectal Dis ; 39(1): 33, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38436757

RESUMO

OBJECTIVE: The use of goal-directed fluid therapy (GDFT) has been shown to reduce complications and improve prognosis in high-risk abdominal surgery patients. However, the utilization of pulse pressure variation (PPV) guided GDFT in laparoscopic surgery remains a subject of debate. We hypothesized that utilizing PPV guidance for GDFT would optimize short-term prognosis in elderly patients undergoing laparoscopic radical resection for colorectal cancer compared to conventional fluid therapy. METHODS: Elderly patients undergoing laparoscopic radical resection of colorectal cancer were randomized to receive either PPV guided GDFT or conventional fluid therapy and explore whether PPV guided GDFT can optimize the short-term prognosis of elderly patients undergoing laparoscopic radical resection of colorectal cancer compared with conventional fluid therapy. RESULTS: The incidence of complications was significantly lower in the PPV group compared to the control group (32.8% vs. 57.1%, P = .009). Additionally, the PPV group had a lower occurrence of gastrointestinal dysfunction (19.0% vs. 39.3%, P = .017) and postoperative pneumonia (8.6% vs. 23.2%, P = .033) than the control group. CONCLUSION: Utilizing PPV as a monitoring index for GDFT can improve short-term prognosis in elderly patients undergoing laparoscopic radical resection of colorectal cancer. REGISTRATION NUMBER: ChiCTR2300067361; date of registration: January 5, 2023.


Assuntos
Neoplasias Colorretais , Laparoscopia , Idoso , Humanos , Pressão Sanguínea , Objetivos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Laparoscopia/efeitos adversos , Hidratação , Neoplasias Colorretais/cirurgia
15.
Nat Commun ; 15(1): 2167, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461148

RESUMO

Developing highly efficient catalysts is significant for Li-CO2 batteries. However, understanding the exact structure of catalysts during battery operation remains a challenge, which hampers knowledge-driven optimization. Here we use X-ray absorption spectroscopy to probe the reconstruction of CoSx (x = 8/9, 1.097, and 2) pre-catalysts and identify the local geometric ligand environment of cobalt during cycling in the Li-CO2 batteries. We find that different oxidized states after reconstruction are decisive to battery performance. Specifically, complete oxidation on CoS1.097 and Co9S8 leads to electrochemical performance deterioration, while oxidation on CoS2 terminates with Co-S4-O2 motifs, leading to improved activity. Density functional theory calculations show that partial oxidation contributes to charge redistributions on cobalt and thus facilitates the catalytic ability. Together, the spectroscopic and electrochemical results provide valuable insight into the structural evolution during cycling and the structure-activity relationship in the electrocatalyst study of Li-CO2 batteries.

16.
Chem Rev ; 124(5): 2839-2887, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38427022

RESUMO

The popularity of portable electronic devices and electric vehicles has led to the drastically increasing consumption of lithium-ion batteries recently, raising concerns about the disposal and recycling of spent lithium-ion batteries. However, the recycling rate of lithium-ion batteries worldwide at present is extremely low. Many factors limit the promotion of the battery recycling rate: outdated recycling technology is the most critical one. Existing metallurgy-based recycling methods rely on continuous decomposition and extraction steps with high-temperature roasting/acid leaching processes and many chemical reagents. These methods are tedious with worse economic feasibility, and the recycling products are mostly alloys or salts, which can only be used as precursors. To simplify the process and improve the economic benefits, novel recycling methods are in urgent demand, and direct recycling/regeneration is therefore proposed as a next-generation method. Herein, a comprehensive review of the origin, current status, and prospect of direct recycling methods is provided. We have systematically analyzed current recycling methods and summarized their limitations, pointing out the necessity of developing direct recycling methods. A detailed analysis for discussions of the advantages, limitations, and obstacles is conducted. Guidance for future direct recycling methods toward large-scale industrialization as well as green and efficient recycling systems is also provided.

17.
Biol Reprod ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38452209

RESUMO

Indoleamine 2, 3-dioxygenase (IDO) plays important roles in maternal immune tolerance. Female Sprague Dawley rats (9-11 weeks old) were randomly divided into an autoplastic transplantation group (n = 75) and an allograft transplantation group (n = 300) further divided into subgroups of ovarian transplantation, allograft ovarian transplantation, allograft ovarian transplantation with cyclosporine A treatment, allograft ovarian transplantation and transfection with IDO-expressing lentiviruses, and allograft ovarian transplantation and transfection with control lentiviruses. IDO was successfully transfected intothe transplanted ovarian tissue. The survival rate, success rate of ovarian transplantation, period until estrous cycle restoration, and estrogen levels of rats that received IDO-expressing lentiviruseswere significantly different from those of rats that underwent allograft transplantation and with control transfection (all P < 0.05), but not significantly different from those of rats that received autoplastic transplantation (all P > 0.05). The number of ovarian follicles in the transplanted ovarian tissue of rats that received IDO-expressing lentiviruses was also significantly higher. The expression level of IDO protein detected by immunohistochemistry and western blotting was especially high in ovaries that had received IDO-containing lentiviruses. Naturally pregnant rats were found in each group postoperatively. These results indicate that IDO-expressing lentiviruses were successfully transfected into transplanted ovarian tissues of rats and that IDO was stably expressed within a certain time. These findings suggest that the expression level of IDO protein is associated with an enhanced success rate of ovarian tissue transplantation and a short restoration period of endocrine function.

18.
Immunity ; 57(3): 478-494.e6, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38447571

RESUMO

Emerging evidence has revealed a direct differentiation route from hematopoietic stem cells to megakaryocytes (direct route), in addition to the classical differentiation route through a series of restricted hematopoietic progenitors (stepwise route). This raises the question of the importance of two alternative routes for megakaryopoiesis. Here, we developed fate-mapping systems to distinguish the two routes, comparing their quantitative and functional outputs. We found that megakaryocytes were produced through the two routes with comparable kinetics and quantity under homeostasis. Single-cell RNA sequencing of the fate-mapped megakaryocytes revealed that the direct and stepwise routes contributed to the niche-supporting and immune megakaryocytes, respectively, but contributed to the platelet-producing megakaryocytes together. Megakaryocytes derived from the two routes displayed different activities and were differentially regulated by chemotherapy and inflammation. Our work links differentiation route to the heterogeneity of megakaryocytes. Alternative differentiation routes result in variable combinations of functionally distinct megakaryocyte subpopulations poised for different physiological demands.


Assuntos
Megacariócitos , Trombopoese , Diferenciação Celular/genética , Células-Tronco Hematopoéticas , Plaquetas
19.
Nat Commun ; 15(1): 2245, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472279

RESUMO

Bifacial perovskite solar cells have shown great promise for increasing power output by capturing light from both sides. However, the suboptimal optical transmittance of back metal electrodes together with the complex fabrication process associated with front transparent conducting oxides have hindered the development of efficient bifacial PSCs. Here, we present a novel approach for bifacial perovskite devices using single-walled carbon nanotubes as both front and back electrodes. single-walled carbon nanotubes offer high transparency, conductivity, and stability, enabling bifacial PSCs with a bifaciality factor of over 98% and a power generation density of over 36%. We also fabricate flexible, all-carbon-electrode-based devices with a high power-per-weight value of 73.75 W g-1 and excellent mechanical durability. Furthermore, we show that our bifacial devices have a much lower material cost than conventional monofacial PSCs. Our work demonstrates the potential of SWCNT electrodes for efficient, stable, and low-cost bifacial perovskite photovoltaics.

20.
J Assist Reprod Genet ; 41(4): 1067-1076, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38438769

RESUMO

PURPOSE: When resecting endometriomas with the stripping technique, in the majority of cases, a thin line of adjacent ovarian cortex is attached to the endometrioma. In this study, we performed histological analysis to determine (antral) follicle density in the ovarian cortex tissue attached to stripped endometriomas and assessed patient- and surgical characteristics that could affect this. METHODS: Histological slides of previously removed endometriomas were assessed. Follicles in the attached ovarian tissue were classified according to maturation, and follicular density was determined. Immunofluorescent staining of antral follicles in a subset of endometriomas was also performed. RESULTS: In 90 out of 96 included endometriomas (93.7%), ovarian tissue attached to the cyst wall was observed. One thousand nine hundred forty-four follicles at different maturation stages were identified (3 follicles/mm3). Follicle density was negatively associated with age (p < 0.001). Antral follicles (< 7-mm diameter) were present in the ovarian tissue attached to 35 endometriomas (36.5%) derived from younger patients compared to endometriomas where none were detected (30 versus 35 years, p = 0.003). Antral follicle density was 1 follicle/mm3. Based on immunofluorescence, healthy antral follicles were identified in two out of four examined endometriomas. CONCLUSIONS: Ovarian tissue attached to stripped endometriomas holds potential as a non-invasive source for antral follicles. In theory, application of IVM could be an interesting alternative FP option in young patients with endometriomas who undergo cystectomy in order to transform the surgical collateral damage to a potential oocyte source. Our results encourage future research with fresh tissue to further assess the quality and potential of these follicles. TRIAL REGISTRATION: Clinical Trials.gov Identifier: B21.055 (METC LDD), date of registration 12-08-2021, retrospectively registered.


Assuntos
Endometriose , Folículo Ovariano , Humanos , Feminino , Endometriose/patologia , Folículo Ovariano/patologia , Folículo Ovariano/crescimento & desenvolvimento , Adulto , Ovário/patologia
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