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1.
Eur J Ophthalmol ; : 11206721241267028, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39094558

RESUMO

OBJECTIVE: This study aims to examine the characteristics and influencing factors of crystalline lens tilt and decentration in ultra-high myopic cataract patients, as measured by the CASIA2. METHODS AND ANALYSIS: 60 eyes scheduled for cataract surgery with an axial length (AL) ≥ 28 mm were included. The IOLMaster700 was utilized to measure AL and the white-to-white (WTW) distance. The CASIA2 was employed to measure front curvature radius (FCR), crystalline lens tilt, and crystalline lens decentration. The relationships between lens tilt, decentration, and related factors were evaluated. RESULTS: The degree of lens tilt was 4.62 ± 2.44°, and the decentration was 0.20 (Q1 0.13, Q3 0.28) mm. Among the 60 eyes, 11 (18.3%) had a tilt ≥7°, and 6 (10%) had a decentratiolens tilt ≥7° (P = 0.038, P = 0.018). Eyes with AL >30.00 mm and FCR <8.45 mm had a higher degree of lens tilt. Additionally, a tilt ≥7° was associated with a greater decentration (P = 0.032), n. CONCLUSION: Preoperative crystalline lenses in eyes with ultra-high myopia and cataract exhibit certain degrees of tilt and decentration. An AL >30 mm is a risk factor for a lens tilt ≥7° and an decentration ≥0.4 mm. An FCR <8.45 mm is a risk factor for increased lens tilt, and a tilt ≥7° is a risk factor for increased lens decentrati ≥ 0.4 mm. An increase in AL and FCR <8.45 mm were risk factors for a and eyes with AL >30.00 mm had a higher degree of decentration (P = 0.005).

2.
Front Psychol ; 15: 1375698, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39108422

RESUMO

Objective: Depression is a common mental illness with a high prevalence rate and is a significant contributor to the global burden of diseases. Various factors are associated with depression, and its etiology is complex. Instead of focusing on single-factor effects, this study aimed to explore a combination of high-risk factor sets for depression among adult community residents. Methods: We conducted a cross-sectional survey in Shenzhen, China, from January 2021 to March 2021. A simple sampling method was used to enroll participants. A total of 1,965 adult residents completed the survey and were assessed using the Patient Health Questionnaire-9 (PHQ-9), the Eysenck Personality Questionnaire-Revised Short Scale for Chinese (EPQ-RSC), and the Psychosocial Stress Survey for Groups (PSSG). The fuzzy-set qualitative comparative analysis method was used to explore the high-risk factor sets for depression among adult community residents. Results: The prevalence of depression among the surveyed adult residents in Shenzhen was 6.36%. The mean scores of PHQ-9 were higher among women and unmarried residents. The combination of low extroversion (e) and high neuroticism (N) in personality traits, along with high scores for life events (V), negative emotional responses to events (G), positive emotional responses to events (O), and positive coping styles to events (I) (denoted as e*N*V*G*O*I) constituted a high-risk factor set for depression. The overall consistency was 0.843, and the overall coverage was 0.330. Conclusion: Our study suggested that stressful life events together with personality traits including neuroticism and introversion serve as crucial factors for depression among adult community residents, regardless of the coping strategies they adopt. This study provides data for developing comprehensive interventions such as regulating neuroticism and introversion levels and reducing stressors to prevent the occurrence of depression among adult community residents.

3.
Transl Androl Urol ; 13(7): 1145-1163, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39100843

RESUMO

Background: Methyltransferase-like (METTL) plays an important role in various biological processes, but its role in prostate cancer (PCa) is still unclear. This study aimed to explore the mechanism by which methyltransferase-like 14 (METTL14) inhibits the physiological activity of PCa cells by increasing the N6-methyladenosine (m6A) modification of cyclin-dependent kinase 4 (CDK4). Methods: Clinical samples were collected for bioinformatics analysis. A PCa mouse model was constructed. Cell counting kit-8 (CCK-8), flow cytometry, colony formation assays, scratch assays, Transwell assays, real-time quantitative polymerase chain reaction (RT-qPCR), immunofluorescence and western blotting were used to detect the corresponding indicators. Results: METTL14 was found to be beneficial to inhibit the proliferation, invasion, and migration of PCa cells. When the m6A RNA increased, the half-life of CDK4 mRNA decreased after oe-METTL14 (overexpression of METTL14). Overexpression of CDK4 reversed the effect of oe-METTL14. Coimmunoprecipitation experiments revealed there were interactions between CDK4 and forkhead box M1 (FOXM1). Transfection of si-CDK4 was similar to transfection of oe-METTL14. After transfection with oe-FOXM1, the invasion and migration ability of cells increased, and cell apoptosis decreased. After transfection with si-FOXM1 alone, autophagy related 7 (ATG7) expression was significantly downregulated, and autophagy levels were reduced. The overexpression of ATG7 reversed the effect of si-FOXM1. The tumor volume and weight of the oe-METTL14 group mice were significantly reduced, and tumor proliferation was decreased in comparison to untreated tumor-bearing mice. Conclusions: METTL14 inhibits the invasion and migration of PCa cells and induces cell apoptosis by inhibiting CDK4 stability and FOXM1/ATG7-mediated autophagy.

4.
Inflammation ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977539

RESUMO

Rheumatic heart disease (RHD) is an important and preventable cause of cardiovascular death and disability, but the lack of clarity about its exact mechanisms makes it more difficult to find alternative methods or prevention and treatment. We previously demonstrated that increased IL-17 expression plays a crucial role in the development of RHD-related valvular inflammatory injury. Macrophage autophagy/polarization may be a pro-survival strategy in the initiation and resolution of the inflammatory process. This study investigated the mechanism by which IL-17 regulates autophagy/polarization activation in macrophages. A RHD rat model was generated, and the effects of anti-IL-17 and 3-methyladenine (3-MA) were analyzed. The molecular mechanisms underlying IL-17-induced macrophage autophagy/polarization were investigated via in vitro experiments. In our established RHD rat model, the activation of the macrophage PINK1/Parkin autophagic pathway in valve tissue was accompanied by M1 macrophage infiltration, and anti-IL-17 treatment inhibited autophagy and reversed macrophage inflammatory infiltration, thereby attenuating endothelial-mesenchymal transition (EndMT) in the valve tissue. The efficacy of 3-MA treatment was similar to that of anti-IL-17 treatment. Furthermore, in THP-1 cells, the pharmacological promotion of autophagy by IL-17 induced M1-type polarization, whereas the inhibition of autophagy by 3-MA reversed this process. Mechanistically, silencing PINK1 in THP-1 blocked autophagic flux. Moreover, IL-17-induced M1-polarized macrophages promoted EndMT in HUVECs. This study revealed that IL-17 plays an important role in EndMT in RHD via the PINK1/Parkin autophagic pathway and macrophage polarization, providing a potential therapeutic target.

5.
Ren Fail ; 46(2): 2374013, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38967153

RESUMO

OBJECTIVE: To evaluate the clinical efficacy and safety of fractionated plasma separation and adsorption combined with continuous veno-venous hemofiltration (FPSA-CVVH) treatment in patients with acute bipyridine herbicide poisoning. METHODS: A retrospective analysis of 18 patients with acute bipyridine herbicide poisoning was conducted, of which 9 patients were poisoned by diquat and 9 patients by paraquat. All patients underwent FPSA-CVVH treatment. The serum cytokine levels in pesticide-poisoned patients were assessed. The efficacy of FPSA-CVVH in eliminating cytokines, the 90-d survival rate of poisoned patients, and adverse reactions to the treatment were observed. RESULTS: Fourteen patients (77.8%) had acute kidney injuries and 10 (55.6%) had acute liver injuries. The serum cytokine levels of high mobility group protein B-1 (HMGB-1), interleukin-6 (IL-6), IL-8, interferon-inducible protein-10 (IP-10), monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-1ß (MIP-1ß) were significantly elevated. A total of 41 FPSA-CVVH treatment sessions were administered. After a single 8-h FPSA-CVVH treatment, the decreases in HMGB-1, IL-6, IL-8, IP-10, MCP-1, and MIP-1ß were 66.0%, 63.5%, 73.3%, 63.7%, 53.9%, and 54.1%, respectively. During FPSA-CVVH treatment, one patient required a filter change due to coagulation in the plasma component separator, and one experienced a bleeding adverse reaction. The 90-d patient survival rate was 50%, with 4 patients with diquat poisoning and 5 patients with paraquat poisoning, and both liver and kidney functions were restored to normal. CONCLUSION: Cytokine storms may play a significant role in the progression of multiorgan dysfunction in patients with acute bipyridine herbicide poisoning. FPSA-CVVH can effectively reduce cytokine levels, increase the survival rate of patients with acute bipyridine herbicide poisoning, and decrease the incidence of adverse events.


Assuntos
Injúria Renal Aguda , Terapia de Substituição Renal Contínua , Herbicidas , Humanos , Masculino , Feminino , Herbicidas/intoxicação , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade , Injúria Renal Aguda/terapia , Injúria Renal Aguda/induzido quimicamente , Citocinas/sangue , Paraquat/intoxicação , Diquat/intoxicação , Adulto Jovem , Idoso , Hemofiltração/métodos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/terapia
6.
Clin Invest Med ; 47(2): 23-39, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38958477

RESUMO

PURPOSE: Over the past 20 years, much of the research on diabetes has focused on pancreatic beta cells. In the last 10 years, interest in the important role of pancreatic alpha cells in the pathogenesis of diabetes, which had previously received little attention, has grown. We aimed to summarize and visualize the hotspot and development trends of pancreatic alpha cells through bibliometric analysis and to provide research direction and future ideas for the treatment of diabetes and other islet-related diseases. METHODS: We used two scientometric software packages (CiteSpace 6.1.R6 and VOSviewer1.6.18) to visualize the information and connection of countries, institutions, authors, and keywords in this field. RESULTS: A total of 532 publications, published in 752 institutions in 46 countries and regions, were included in this analysis. The United States showed the highest output, accounting for 39.3% of the total number of published papers. The most active institution was Vanderbilt University, and the authors with highest productivity came from Ulster University. In recent years, research hotspots have concentrated on transdifferentiation, gene expression, and GLP-1 regulatory function. Visualization analysis shows that research hotspots mainly focus on clinical diseases as well as physiological and pathological mechanisms and related biochemical indicators. CONCLUSIONS: This study provides a review and summary of the literature on pancreatic alpha cells through bibliometric and visual methods and shows research hotspot and development trends, which can guide future directions for research.


Assuntos
Bibliometria , Células Secretoras de Glucagon , Humanos , Células Secretoras de Glucagon/metabolismo , Pesquisa Biomédica/tendências , Animais , Diabetes Mellitus
7.
Drug Des Devel Ther ; 18: 2555-2570, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952487

RESUMO

Purpose: The aim of this review was to provide all the pharmacokinetic data for semaglutide in humans concerning its pharmacokinetics after subcutaneously and oral applications in healthy and diseased populations, to provide recommendations for clinical use. Methodology: The PubMed and Embase databases were searched to screen studies associated with the pharmacokinetics of semaglutide. The pharmacokinetic parameters included area under the curve plasma concentrations (AUC), maximal plasma concentration (Cmax), time to Cmax, half-life (t1/2), and clearance. The systematic literature search retrieved 17 articles including data on pharmacokinetic profiles after subcutaneously and oral applications of semaglutide, and at least one of the above pharmacokinetic parameter was reported in all included studies. Results: Semaglutide has a predictable pharmacokinetic profile with a long t1/2 that allows for once-weekly subcutaneous administration. The AUC and Cmax of both oral and subcutaneous semaglutide increased with dose. Food and various dosing conditions including water volume and dosing schedules can affect the oral semaglutide exposure. There are limited drug-drug interactions and no dosing adjustments in patients with upper gastrointestinal disease, renal impairment or hepatic impairment. Body weight may affect semaglutide exposure, but further studies are needed to confirm this. Conclusion: This review encompasses all the pharmacokinetic data for subcutaneous and oral semaglutide in both healthy and diseased participants. The existing pharmacokinetic data can assist in developing and evaluating pharmacokinetic models of semaglutide and will help clinicians predict semaglutide dosages. In addition, it can also help optimize future clinical trials.


Assuntos
Peptídeos Semelhantes ao Glucagon , Peptídeos Semelhantes ao Glucagon/farmacocinética , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Humanos , Administração Oral , Injeções Subcutâneas , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/administração & dosagem , Interações Medicamentosas
9.
Water Res ; 263: 122147, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39084093

RESUMO

Human-induced nutrient inputs to global coastal waters are leading to increasing nutrients and escalating eutrophication. However, how aquatic ecosystem functioning responds to these changes remains insufficiently studied. Here we report the long-term changes in the nutrient regime and planktonic ecosystem functioning in the Daya Bay, a typical subtropical semi-enclosed bay experiencing rapid economic and social development for several decades. Time-series (from 1991 to 2018) data with a mostly quarterly resolution were collected to depict long-term changes in dissolved inorganic nutrients and plankton abundances, based on which we constructed simplified abundance size spectra (SASS) and plankton abundance ratios to describe the functioning of the planktonic ecosystem. The results revealed a long-term increase in system productivity but a decrease in integrated energy transfer efficiency of the planktonic ecosystem, with rising concentrations of dissolved inorganic nitrogen (DIN). Shifts in the nutrient regime and planktonic ecosystem functioning were detected at a tipping point or threshold around 2006-2007. The shifts were characterized by abrupt changes in the trends of nutrient (phosphate, ammonia, nitrite) concentrations, nutrient ratios (DIN/phosphate, silicate/phosphate), plankton abundance, and total plankton biomass. Compared to the nutrient regime, the planktonic ecosystem functioning shifted several years later. Overall, this study indicates that the pelagic ecosystem regime can shift significantly in response to long-term increasing input of human-induced nutrients in coastal waters such as the Daya Bay. The regime shifts may have profound implications for fishery production, and ecosystem management in the bay.

10.
Biomedicines ; 12(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39062041

RESUMO

Cervical squamous cell carcinoma (CSCC) represents a significant global health concern among females. Identifying new biomarkers and therapeutic targets is pivotal for improving the prognosis of CSCC. This study investigates the prognostic relevance of CCZ1 in CSCC and elucidates its downstream pathways and targets using a combination of bioinformatics analysis and experimental validation. Transcriptomic analysis of 239 CSCC and 3 normal cervical samples from The Cancer Genome Atlas database reveals a marked upregulation of CCZ1 mRNA levels in CSCC, and elevated CCZ1 mRNA levels were associated with poor prognosis. Immunohistochemical analysis of clinical samples also confirmed these findings. Furthermore, functional assays, including Cell Counting Kit-8, colony formation, Transwell, and flow cytometry, elucidated the influence of CCZ1 on CSCC cell proliferation, migration, invasion, and cell cycle progression. Remarkably, CCZ1 knockdown suppressed CSCC progression both in vitro and in vivo. Mechanistically, CCZ1 knockdown downregulated MMP2 and MMP17 expression. Restoring MMP2 or MMP17 expression rescued phenotypic alterations induced by CCZ1 knockdown. Hence, CCZ1 promotes CSCC progression by upregulating MMP2 and MMP17 expression, emerging as a novel biomarker in CSCC and presenting potential as a therapeutic target in CSCC.

11.
BMC Med Res Methodol ; 24(1): 165, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080524

RESUMO

BACKGROUND: Standard systematic review can be labor-intensive and time-consuming meaning that it can be difficult to provide timely evidence when there is an urgent public health emergency such as a pandemic. The ClinicalTrials.gov provides a promising way to accelerate evidence production. METHODS: We conducted a search on PubMed to gather systematic reviews containing a minimum of 5 studies focused on safety aspects derived from randomized controlled trials (RCTs) of pharmacological interventions, aiming to establish a real-world dataset. The registration information of each trial from eligible reviews was further collected and verified. The meta-analytic data were then re-analyzed by using 1) the full meta-analytic data with all trials and 2) emulated rapid data with trials that had been registered and posted results on ClinicalTrials.gov, under the same synthesis methods. The effect estimates of the full meta-analysis and rapid meta-analysis were then compared. RESULTS: The real-world dataset comprises 558 meta-analyses. Among them, 56 (10.0%) meta-analyses included RCTs that were not registered in ClinicalTrials.gov. For the remaining 502 meta-analyses, the median percentage of RCTs registered within each meta-analysis is 70.1% (interquartile range: 33.3% to 88.9%). Under a 20% bias threshold, rapid meta-analyses conducted through ClinicalTrials.gov achieved accurate point estimates ranging from 77.4% (using the MH model) to 83.1% (using the GLMM model); 91.0% to 95.3% of these analyses accurately predicted the direction of effects. CONCLUSIONS: Utilizing the ClinicalTrials.gov platform for safety assessment with a minimum of 5 RCTs holds significant potential for accelerating evidence synthesis to support urgent decision-making.


Assuntos
Estudos de Viabilidade , Metanálise como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Revisões Sistemáticas como Assunto/métodos , Sistema de Registros/estatística & dados numéricos , Bases de Dados Factuais/estatística & dados numéricos
12.
J Med Chem ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044437

RESUMO

Triple-negative breast cancer (TNBC) is a highly lethal malignancy, and its clinical management encounters severe challenges due to its high metastatic propensity and the absence of effective therapeutic targets. To improve druggability of aurovertin B (AVB), a natural polyketide with a significant antiproliferative effect on TNBC, a series of NO donor/AVB hybrids were synthesized and tested for bioactivities. Among them, compound 4d significantly inhibited the proliferation and metastasis of TNBC in vitro and in vivo with better safety than that of AVB. The structure-activity relationship analysis suggested that the types of NO donor and the linkers had considerable effects on the activities. Mechanistic investigations unveiled that 4d induced apoptosis and ferroptosis by the reduction of mitochondrial membrane potential and the down-regulation of GPX4, respectively. The antimetastatic effect of 4d was associated with the upregulation of DUSP1. Overall, these compelling results underscore the tremendous potential of 4d for treating TNBC.

13.
Adv Mater ; : e2311501, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39049723

RESUMO

The perovskite/silicon tandem solar cell represents one of the most promising avenues for exceeding the Shockley-Queisser limit for single-junction solar cells at a reasonable cost. Remarkably, its efficiency has rapidly increased from 13.7% in 2015 to 34.6% in 2024. Despite the significant research efforts dedicated to this topic, the "secret" to achieving high-performance perovskite/silicon tandem solar cells seems to be confined to a few research groups. Additionally, the discrepancies in preparation and characterization between single-junction and tandem solar cells continue to impede the transition from efficient single-junction to efficient tandem solar cells. This review first revisits the key milestones in the development of monolithic perovskite/silicon tandem solar cells over the past decade. Then, a comprehensive analysis of the background, advancements, and challenges in perovskite/silicon tandem solar cells is provided, following the sequence of the tandem fabrication process. The progress and limitations of the prevalent stability measurements for tandem devices are also discussed. Finally, a roadmap for designing efficient, scalable, and stable perovskite/silicon tandem solar cells is outlined. This review takes the growth history into consideration while charting the future course of perovskite/silicon tandem research.

14.
Mar Pollut Bull ; 206: 116737, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39053263

RESUMO

Hexabromocyclododecanes (HBCDs) are legacy additive brominated flame retardant. In present study, the distribution, biomagnification and potential human health risk associated with HBCDs were investigated in six edible marine fish species collected from three bays in the Beibu Gulf, China, between March and October 2021. The concentration of HBCDs ranged from 0.05 to 200 ng/g lipid weight (lw), with Scoliodon laticaudus and Trichiurus nanhaiensis having the highest and lowest concentration, respectively. The α-HBCD was dominant in most studied fish, expect for Scoliodon laticaudus. Dietary source was the primary factor for the diastereomeric profiles of HBCDs in fish. Only γ-HBCD demonstrated trophic magnification in the studied fish species. Finally, the estimated daily intake (EDI) was 0.18 ng/kg/day for adults, 0.17 ng/kg/day for teenager and children, and all corresponding margin of exposure (MOE) values were lager than 8 indicating relatively low human exposure risks from fish consumption.

15.
J Affect Disord ; 363: 292-299, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39029686

RESUMO

BACKGROUND: Depression is a significant public health issue, closely associated with epilepsy and oxidative stress (OS). This study aims to explore the level of OS in patients with epilepsy and its relationship with moderate to severe depression (MSD). METHODS: This cross-sectional study includes 10,819 participants aged 20-80 from the National Health and Nutrition Examination Survey (NHANES) database (2013-2020 pre-pandemic). Depression symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9), and epilepsy was diagnosed based on antiepileptic drug use in the past 30 days. The oxidative balance score (OBS) was calculated from dietary recall and lifestyle habits over the previous 24 h. RESULTS: Compared to non-epileptic subjects, epileptic patients have a significantly higher prevalence of depression. Epileptic patients exhibit lower OBS and Dietary Oxidative Balance Scores (DOBS), while there is no significant difference in Lifestyle Oxidative Balance Scores (LOBS). Depressed patients show lower OBS, DOBS, and LOBS. The mediation model indicates that DOBS mediates 3.44 % of epilepsy-related MSD. CONCLUSIONS: Epileptic patients exhibit significantly higher levels of OS and consume more pro-oxidant foods compared to the general population. However, their lifestyle habits do not differ significantly from those of the control group. Additionally, epileptic patients are at a higher risk of developing MSD. Although a pro-oxidant diet may be associated with epilepsy-mediated MSD, its mediating effect is relatively weak.

16.
Adv Radiat Oncol ; 9(8): 101549, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39055959

RESUMO

Purpose: Exosomes have been shown to play a role in most, if not all, steps of cancer progression. We still lack a comprehensive understanding of the bidirectional communication of exosomes between tumor cells and immune cells. This article aims to explore how exosomes can influence cancer growth and how they are affected by radiation therapy. Methods and Materials: We searched on PubMed and Web of Science on the impact of radiation on tumor derived exosomes and immune cell derived exosomes in tumor immune microenvironment. We screened all the related articles and summarized their main discoveries and important results. Results: This article reviewed the effects of tumor derived exosomes and immune cell-derived exosomes on TME and tumor progression after radiotherapy, suggesting the dual effects of exosomes which may refer to clinical practice. Moreover, we retrospected the clinical applications based on tumor derived exosomes, including liquid biopsy, radio-resistance and drug delivery, and discussed the challenges and prospects. Conclusions: Exosomes are important in cancer treatment, especially with radiation therapy. Learning more about them could lead to better treatments. However, there are still challenges to overcome. The review points out the need for more research in this area.

17.
Curr Biol ; 34(15): 3454-3472.e7, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39059395

RESUMO

Most land plants alternate between generations of sexual gametophytes and asexual sporophytes. Unlike seed plants, fern gametophytes are free living and grow independently of their sporophytes. In homosporous ferns such as Ceratopteris, gametophytes derived from genetically identical spores exhibit sexual dimorphism, developing as either males or hermaphrodites. Males lack meristems and promote cell differentiation into sperm-producing antheridia. In contrast, hermaphrodites initiate multicellular meristems that stay undifferentiated, sustain cell division and prothallus expansion, and drive the formation of egg-producing archegonia. Once initiating the meristem, hermaphrodites secrete the pheromone antheridiogen, which triggers neighboring slower-growing gametophytes to develop as males, while the hermaphrodites themselves remain insensitive to antheridiogen. This strategy promotes outcrossing and prevents all individuals in the colony from becoming males. This study reveals that an evolutionarily conserved GRAS-domain transcriptional regulator (CrHAM), directly repressed by Ceratopteris microRNA171 (CrmiR171), promotes meristem development in Ceratopteris gametophytes and determines the male-to-hermaphrodite ratio in the colony. CrHAM preferentially accumulates within the meristems of hermaphrodites but is excluded from differentiated antheridia. CrHAM sustains meristem proliferation and cell division through conserved hormone pathways. In the meantime, CrHAM inhibits the antheridiogen-induced conversion of hermaphrodites to males by suppressing the male program expression and preventing meristem cells from differentiating into sperm-producing antheridia. This finding establishes a connection between meristem indeterminacy and sex determination in ferns, suggesting both conserved and diversified roles of meristem regulators in land plants.


Assuntos
Células Germinativas Vegetais , Meristema , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Células Germinativas Vegetais/crescimento & desenvolvimento , Células Germinativas Vegetais/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Pteridaceae/genética , Pteridaceae/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Processos de Determinação Sexual
18.
Water Res ; 261: 122043, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38981351

RESUMO

The bioaccumulation and trophic transfer of organophosphate flame retardants (OPFRs) in marine ecosystems have attracted great attention in recent research, but our understanding of the trophic transfer mechanisms involved is limited. In this study, we investigated the trophodynamics of OPFRs and their metabolites in a subtropical coastal food web collected from the northern Beibu Gulf, China, and characterized their trophodynamics using fugacity- and biotransformation-based approaches. Eleven OPFRs and all seven metabolites were simultaneously quantified in the shellfish, crustacean, pelagic fish, and benthic fish samples, with total concentrations ranging from 164 to 4.11 × 104 and 4.56-4.28 × 103 ng/g lipid weight, respectively. Significant biomagnification was observed only for tris (phenyl) phosphate (TPHP) and tris (2-ethylhexyl) phosphate (TEHP), while other compounds except for tris(2-chloroethyl) phosphate (TCEP) displayed biomagnification trends based on Monte Carlo simulations. Using a fugacity-based approach to normalize the accumulation of OPFRs in biota to their relative biological phase composition, storage lipid is the predominant biological phase for the mass distribution of 2-ethylhexyl diphenyl phosphate (EHDPHP) and TPHP. The water content and structure protein are equally important for TCEP, whereas lipid and structure protein are the two most important phases for other OPFRs. The mass distribution of these OPFRs along with TLs can explain their trophodynamics in the food web. The organophosphate diesters (as OPFR metabolites) also displayed biomagnification trends based on bootstrapped estimation. The correlation analysis and Korganism-water results jointly suggested the metabolites accumulation in high-TL organisms was related to biotransformation processes. The metabolite-backtracked trophic magnification factors for tri-n­butyl phosphate (TNBP) and TPHP were both greater than the values that accounted for only the parent compounds. This study highlights the incorporation of fugacity and biotransformation analysis to characterize the trophodynamic processes of OPFRs and other emerging pollutants in food webs.


Assuntos
Biotransformação , Retardadores de Chama , Cadeia Alimentar , Organofosfatos , Poluentes Químicos da Água , Retardadores de Chama/metabolismo , Organofosfatos/metabolismo , Animais , China , Poluentes Químicos da Água/metabolismo , Peixes/metabolismo , Monitoramento Ambiental
19.
Front Oncol ; 14: 1407016, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39040460

RESUMO

Purpose: Difficulties remain in dose optimization and evaluation of cervical cancer radiotherapy that combines external beam radiotherapy (EBRT) and brachytherapy (BT). This study estimates and improves the accumulated dose distribution of EBRT and BT with deep learning-based dose prediction. Materials and methods: A total of 30 patients treated with combined cervical cancer radiotherapy were enrolled in this study. The dose distributions of EBRT and BT plans were accumulated using commercial deformable image registration. A ResNet-101-based deep learning model was trained to predict pixel-wise dose distributions. To test the role of the predicted accumulated dose in clinic, each EBRT plan was designed using conventional method and then redesigned referencing the predicted accumulated dose distribution. Bladder and rectum dosimetric parameters and normal tissue complication probability (NTCP) values were calculated and compared between the conventional and redesigned accumulated doses. Results: The redesigned accumulated doses showed a decrease in mean values of V50, V60, and D2cc for the bladder (-3.02%, -1.71%, and -1.19 Gy, respectively) and rectum (-4.82%, -1.97%, and -4.13 Gy, respectively). The mean NTCP values for the bladder and rectum were also decreased by 0.02‰ and 0.98%, respectively. All values had statistically significant differences (p < 0.01), except for the bladder D2cc (p = 0.112). Conclusion: This study realized accumulated dose prediction for combined cervical cancer radiotherapy without knowing the BT dose. The predicted dose served as a reference for EBRT treatment planning, leading to a superior accumulated dose distribution and lower NTCP values.

20.
Int J Biol Macromol ; 276(Pt 2): 133798, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992555

RESUMO

In this paper, the size-controllable nano­silver particles (AgNPs) were synthesized from walnut green husk polysaccharide, and its cytotoxicity and antibacterial activity were evaluated. Firstly, acidic polysaccharide WGHP2 was extracted from walnut green husk, and then the silver ion in AgNO3 was reduced in WGHP2 aqueous solution using NaBH4, so as to synthesize the nano­silver composite. The nano­silver composite was characterized by transmission electron microscope, Fourier infrared spectroscopy, ultraviolet-visible spectrometer, scanning electron microscope, inductively coupled plasma mass spectrometry and X-ray photoelectron spectroscopy. The results show that AgNPs stabilized by WGHP2 are mainly regular spheres with an average particle size distribution of 15.04-19.23 nm. The particle size distribution and morphology of AgNPs changed with the concentration of silver precursor, which is related to the dispersion of silver precursor in polysaccharide aqueous solution and the formation of AgO coordination bond between silver precursor and polysaccharide molecules. These coordination bonds changed the ability of nanoparticles to produce and release Ag+, and thus regulated their antibacterial activity and cytotoxicity, as evidenced by the experimental result of the cytotoxicity of the nano­silver particle against PC12 cells and the bacteriostatic effect on E.coli and S.aureus. Conclusively, WGHP2-Ag has good stability, antibacterial activity and low cytotoxicity.

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