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1.
Sci Total Environ ; 926: 171936, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38527554

RESUMO

There is limited understanding regarding the changes in the ecological processes and the mechanisms of archaeal community in response to heavy metal contamination in the marine sediments. In this study, sediment samples were collected from 46 locations near harbors, and the concentration of heavy metals and the diversity of archaeal communities were investigated to understand the impact of Cd on archaeal communities. The results demonstrated a significant correlation between the diversity of archaeal community and Cd concentration, particularly showing a linear decrease in the species richness with rising Cd concentration. ANME-1b was identified as a significantly enriched archaeal taxon in the higher Cd environment. Null model and neutral community model indicated that the ecological assembly of archaeal communities in marine sediments was primarily governed by the stochastic processes, with dispersal limitation being the primary factor. The contribution of deterministic process to the assembly of archaeal communities in higher Cd environments increased clearly, accompanied by a notable reduction in species migration rates and widths of ecological niche of archaeal populations. Co-occurrence network analysis revealed an obvious increase in species interactions in higher Cd environments, with an apparent rise in the proportion of competitive relationships and an increase in the number of keystone species. Moreover, archaeal species formed a more complex and stable community to cope with Cd stress. This study provides new insights into the impacts of heavy metals on the ecological processes of marine microorganisms and the underlying mechanisms.


Assuntos
Archaea , Metais Pesados , Archaea/genética , Cádmio/análise , Sedimentos Geológicos , RNA Ribossômico 16S/análise , Metais Pesados/análise
2.
Eur J Nutr ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478042

RESUMO

BACKGROUND: While folic acid (FA) is widely used to treat elevated total homocysteine (tHcy), promoting vascular health by reducing vascular oxidative stress and modulating endothelial nitric oxide synthase, the optimal daily dose and individual variation by MTHFR C677T genotypes have not been well studied. Therefore, this study aimed to explore the efficacy of eight different FA dosages on tHcy lowering in the overall sample and by MTHFR C677T genotypes. METHODS: This multicentered, randomized, double-blind, controlled clinical trial included 2697 eligible hypertensive adults with elevated tHcy (≥ 10 mmol/L) and without history of stroke and cardiovascular disease. Participants were randomized into eight dose groups of FA combined with 10 mg enalapril maleate, taken daily for 8 weeks of treatment. RESULTS: The intent to treat analysis included 2163 participants. In the overall sample, increasing FA dosage led to steady tHcy reduction within the FA dosing range of 0-1.2 mg. However, a plateau in tHcy lowering was observed in FA dose range of 1.2-1.6 mg, indicating a ceiling effect. In contrast, FA doses were positively and linearly associated with serum folate levels without signs of plateau. Among MTHFR genotype subgroups, participants with the TT genotype showed greater efficacy of FA in tHcy lowering. CONCLUSIONS: This randomized trial lent further support to the efficacy of FA in lowering tHcy; more importantly, it provided critically needed evidence to inform optimal FA dosage. We found that the efficacy of FA in lowering tHcy reaches a plateau if the daily dosage exceeds 1.2 mg, and only has a small gain by increasing the dosage from 0.8 to 1.2 mg. GOV IDENTIFIER: NCT03472508 (Registration Date: March 21, 2018).

3.
Biochem Genet ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526708

RESUMO

The study aims to explore the fluctuating expression of C/EBP Homologous Protein (CHOP) following rat carotid artery injury and its central role in vascular stenosis. Using in vivo rat carotid artery injury models and in vitro ischemia and hypoxia cell models employing human aortic endothelial cells (HAECs) and vascular smooth muscle cells (T/G HA-VSMCs), a comprehensive investigative framework was established. Histological analysis confirmed intimal hyperplasia in rat models. CHOP expression in vascular tissues was assessed using Western blot and immunohistochemical staining, and its presence in HAECs and T/G HA-VSMCs was determined through RT-PCR and Western blot. The study evaluated HAEC apoptosis, inflammatory cytokine secretion, cell proliferation, and T/G HA-VSMCs migration through Western blot, ELISA, CCK8, and Transwell migration assays. The rat carotid artery injury model revealed substantial fibrous plaque formation and vascular stenosis, resulting in an increased intimal area and plaque-to-lumen area ratio. Notably, CHOP is markedly elevated in vessels of the carotid artery injury model compared to normal vessels. Atorvastatin effectively mitigated vascular stenosis and suppresses CHOP protein expression. In HAECs, ischemia and hypoxia-induced CHOP upregulation, along with heightened TNFα, IL-6, caspase3, and caspase8 levels, while reducing cell proliferation. Atorvastatin demonstrated a dose-dependent suppression of CHOP expression in HAECs. Downregulation of CHOP or atorvastatin treatment led to reduced IL-6 and TNFα secretion, coupled with augmented cell proliferation. Similarly, ischemia and hypoxia conditions increased CHOP expression in T/G HA-VSMCs, which was concentration-dependently inhibited by atorvastatin. Furthermore, significantly increased MMP-9 and MMP-2 concentrations in the cell culture supernatant correlated with enhanced T/G HA-VSMCs migration. However, interventions targeting CHOP downregulation and atorvastatin usage curtailed MMP-9 and MMP-2 secretion and suppressed cell migration. In conclusion, CHOP plays a crucial role in endothelial injury, proliferation, and VSMCs migration during carotid artery injury, serving as a pivotal regulator in post-injury fibrous plaque formation and vascular remodeling. Statins emerge as protectors of endothelial cells, restraining VSMCs migration by modulating CHOP expression.

4.
Am J Clin Nutr ; 119(3): 821-828, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38432716

RESUMO

BACKGROUND: The optimal dosage range for B-vitamin supplementation for stroke prevention has not received sufficient attention. OBJECTIVE: Our aim was to determine the optimal dosage range of a combination of folic acid, vitamin B12, and vitamin B6 supplementation in stroke prevention. METHODS: We searched PubMed, the Cochrane Central Register of Controlled Trials, and Embase database for randomized controlled trials published between January 1966 and April 2023, whose participants received B-vitamin supplementation and that reported the number of stroke cases. Relative risk (RR) was used to measure the effect of combined supplementation on risk of stroke using a fixed-effects model. Risk of bias was assessed with the Cochrane risk-of-bias algorithm. RESULTS: The search identified 14 randomized controlled trials of folic acid combined with vitamin B12 and vitamin B6 supplementation for stroke prevention that included 76,664 participants with 2720 stroke cases. In areas without and with partial folic acid fortification, combined B-vitamin supplementation significantly reduced the risk of stroke by 34% [RR: 0.66; 95% confidence interval (CI): 0.50, 0.86] and 11% (RR: 0.89; 95% CI: 0.79, 1.00), respectively. Further analysis showed that a dosage of folic acid ≤0.8 mg/d and vitamin B12 ≤0.4 mg/d was best for stroke prevention (RR: 0.65; 95% CI: 0.48, 0.86) in these areas. In contrast, no benefit of combined supplementation was found in fortified areas (RR: 1.04; 95% CI: 0.94, 1.16). CONCLUSIONS: Our meta-analysis found that the folic acid combined with vitamin B12 and vitamin B6 supplementation strategy significantly reduced the risk of stroke in areas without and with partial folic acid fortification. Combined dosages not exceeding 0.8 mg/d for folic acid and 0.4 mg/d for vitamin B12 supplementation may be more effective for populations within these areas. This trial was registered at PROSPERO asCRD42022355077.


Assuntos
Acidente Vascular Cerebral , Vitaminas , Humanos , Vitamina B 12/uso terapêutico , Ácido Fólico/uso terapêutico , Vitamina B 6/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Suplementos Nutricionais
5.
Adv Healthc Mater ; : e2304400, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38551206

RESUMO

The management of critical-sized bone defects presents a formidable clinical challenge, especially given the increasing incidence of bone diseases in the aging population. Consequently, there is an increased demand for minimally invasive bone repair materials that can effectively address this challenge, particularly in outpatient settings. In this study, the goal is to develop an injectable and biodegradable biomaterial that adheres to and fills bone-defect sites to support bone regeneration. The osteogenic and angiogenic activities of animal horn peptides are investigated by incorporating them into biologically active moieties, in combination with a novel thermosensitive hydrogel. The resulting thermosensitive hydrogel exhibited essential biological functionalities, allowing precise modulation of its physical and chemical properties. Notably, the hydrogel incorporating the horn peptide rapidly filled the bone defect site, promoting both angiogenesis and bone induction. Consequently, this approach significantly accelerates new bone regeneration. In summary, the findings of this study present a promising, minimally invasive solution for addressing critical-sized bone defects.

6.
Adv Healthc Mater ; : e2303527, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411334

RESUMO

Pathological angiogenesis with subsequent disturbed microvascular remodeling is a major cause of irreversible blindness in a number of ischemic retinal diseases. The current anti-vascular endothelial growth factor therapy can effectively inhibit angiogenesis, but it also brings significant side effects. The emergence of stem cell derived extracellular vesicles provides a new underlining strategy for ischemic retinopathy. Apoptotic vesicles (apoVs) are extracted from stem cells from human exfoliated deciduous teeth (SHED). SHED-apoVs are delivered into the eyeballs of oxygen-induced retinopathy (a most common model of angiogenic retinal dieseases) mice through intravitreal injection. The retinal neovascularization and nonperfusion area, vascular structure, and density changes are observed during the neovascularization phase (P17) and vascular remodeling phase (P21), and visual function is measured. The expression of extracellular acidification rate and lactic acid testing are used to detect endothelial cells (ECs) glycolytic activity. Furthermore, lentivirus and neutralizing antibody are used to block PD1-PDL1 axis, investigating the effects of SHED-apoVs on glycolysis and angiogenic activities. This work shows that SHED-apoVs are taken up by ECs and modulate the ECs glycolysis, leading to the decrease of abnormal neovessels and vascular remodeling. Furthermore, it is found that, at the molecular level, apoVs-carried PD1 interacts with PDL1 on hypoxic ECs to regulate the angiogenic activation. SHED-apoVs inhibit pathological angiogenesis and promote vascular remodeling in ischemic retinopathy partially by modulating ECs glycolysis through PD1/PDL1 axis. This study provides a new potential strategy for the clinical treatment of pathological retinal neovascularization.

7.
Sci Total Environ ; 921: 171194, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38408677

RESUMO

Soil near waste rock often contains high concentrations of antimony (Sb), but the mechanisms that mobilize Sb in a soil closely impacted by the waste rock piles are not well understood. We investigated these mobility mechanisms in soils near historical waste rock at the world's largest Sb mine. The sequential extraction (BCR) of soil reveal that over 95 % Sb is present in the residual fraction. The leached Sb concentration is related to the surface protonation and deprotonation of soil minerals. SEM-EDS shows Sb in the soil is associated with Fe and Ca. Moreover, X-ray absorption spectroscopy (XAS) results show Sb is predominantly present as Sb(V) and is associated with Fe in the form of tripuhyite (FeSbO4) as well as edge- and corner-sharing complexes on ferrihydrite and goethite. Thus, Fe in soils is important in controlling the mobility of Sb via surface complexation and co-precipitation of Sb by Fe oxides. The initially surface-adsorbed Sb(V) or co-precipitation is likely to undergo a phase transformation as the Fe oxides age. In addition, Sb mobility may be controlled by small amounts of calcium antimonate. These results further the understanding of the effect of secondary minerals in soils on the fate of Sb from waste rock weathering and inform source treatment for Sb-contaminated soils.

8.
BMC Geriatr ; 24(1): 187, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402390

RESUMO

BACKGROUND: Hypertension and frailty often occur concurrently, exhibiting increasing prevalence in the older population. In this study, we analyzed the frailty status among older adults with hypertension and the impact of their interaction on death risk. METHOD: This prospective cohort survey study included data from older people in an urban community in Beijing collected between 2009 and 2020 using the cluster random sampling method. The participants were older adults who were ≥ 60 years old at the time of investigation and had lived at the place of investigation for > 1 year. The survey variables comprised those related to health and frailty status assessed during the 2009 baseline survey, along with death-related information as outcome variables in 2020. Additionally, a frailty index (FI) model was used to examine the frailty status among the older adults at baseline. The effects of hypertension prevalence on the age-related frailty changes as well as on mortality for varying degrees of frailty were further analyzed. Lastly, Cox regression and Kaplan-Meier curves were applied to evaluate the impact of the interaction between hypertension and frailty on death risk. RESULTS: Ultimately, 1197 older individuals aged between 60 and 101 years(average age at baseline: 74.8 ± 8.6 years) were included .Among them, 475 individuals were men (mean age:74.8 ± 8.8 years), and 722 were women (mean age:74.8 ± 8.4 years).Frailty was identified in 151 individuals, leading to a prevalence rate of 12.6%(151/1197),while hypertension was detected in 593 (prevalence rate:49.5% [593/1197]).A total of 443 deaths were recorded by 2020, resulting in a mortality rate of 37.0% (443/1197).Moreover, FI values and mortality rates were higher at any age in older adults with hypertension compared with those without hypertension. Survival time analysis showed that the median survival time of older adults with hypertension and frailty was the shortest (39.0[95%CI: 35.6-42.3] months)when compared with that of older adults without hypertension but with frailty (52.9 [95%CI: 46.6-59.3] months), those with hypertension but without frailty (102.7 [95%CI: 98.7-106.8] months), and those without hypertension and frailty (127.9 [95%CI: 113.5-134.7] months),with log-rank x2 = 999.686 and P < 0.001. Furthermore, Cox regression results demonstrated that older adults with hypertension and frailty had the highest death risk when compared with that of older adults without hypertension and frailty (HR = 1.792, P < 0.001), those without hypertension but with frailty (HR = 1.484, P < 0.001), and those with hypertension but without frailty (HR = 1.406, P = 0.005). CONCLUSION: Frailty is prevalent among older adults with hypertension; however, older adults with both hypertension and frailty have a relatively higher mortality risk. Therefore, screening and assessment of frailty in the older population with hypertension are crucial for its early identification, thereby enabling timely and appropriate interventions to prevent or delay the adverse effects of this concurrent condition.


Assuntos
Fragilidade , Hipertensão , Masculino , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Seguimentos , Estudos Prospectivos , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Projetos de Pesquisa , Idoso Fragilizado , Avaliação Geriátrica/métodos
9.
Langmuir ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329721

RESUMO

The coexistence of lead, zinc, and copper ions in wastewater constitutes an environmental challenge of pressing concern. This research delves into the preparation of innovative oxidation-doped conjugated microporous poly(aniline) frameworks, exploring their prospective efficacy in regulating lead ion adsorption from aqueous solutions. H2SO4-CMPTA demonstrates the capability to reach adsorption equilibrium within 15 min at a lead concentration of 50 ppm. Even at a lead concentration of 20 ppm, it still efficaciously attenuates these levels to sub-10 ppb, a value surpassing extant standard. H2SO4-CMPTA retains over 78.8% adsorption efficiency after six cycles. Analytical characterization coupled with computational calculations suggests that sulfate-coordinated nitrogen cationic structure plays a crucial role in adsorption. A deeper investigation reveals the cardinal role of electrostatic attraction and exclusive chelation adsorption underpinning the efficient capture of lead ions by doped sulfate ions. Intriguingly, in a mixed heavy metal solution containing lead, zinc, and copper ions, H2SO4-CMPTA exhibits an initial predilection toward zinc ions, yet an eventual ion-exchange adsorption gravitating toward lead ions was discerned, governed by the latter's superior binding energy. Our study elucidates a promising material as an efficacious tool for the remediation of aquatic environments tainted with lead contaminants.

10.
J Med Chem ; 67(2): 1044-1060, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38173250

RESUMO

Antimicrobial peptides (AMPs) offer an opportunity to overcome multidrug resistance. Here, novel peptides were designed based on AMP fragments derived from sea cucumber hemolytic lectin to enhance anti-methicillin-resistant Staphylococcus aureus (MRSA) activity with less side effects. Two designed peptides, CGS19 (LARVARRVIRFIRRAW-NH2) and CGS20 (RRRLARRLIFFIRRAW-NH2), exhibited strong antibacterial activities against clinically isolated MRSA with MICs of 3-6 µM, but no obvious cytotoxicity was observed. Consistently, CGS19 and CGS20 exerted rapid bactericidal activity and effectively induced 5.9 and 5.8 log reduction of MRSA counts in mouse subeschar, respectively. Further, CGS19 and CGS20 kill bacteria not only through disturbing membrane integrity but also by binding formate-tetrahydrofolate ligase, a key enzyme in the folate metabolism pathway, thereby inhibiting the folate pathway of MRSA. CGS19 and CGS20 are promising lead candidates for drug development against MRSA infection. The dual mechanisms on the identical peptide sequence or scaffold might be an underappreciated manner of treating life-threatening pathogens.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Camundongos , Animais , Antibacterianos/farmacologia , Peptídeos/farmacologia , Testes de Sensibilidade Microbiana , Sequência de Aminoácidos
11.
Trauma Violence Abuse ; : 15248380241226618, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38265028

RESUMO

Dating and sexual violence (DSV) is a common occurrence among school aged youth and has been associated with numerous harmful long-term outcomes. The goal of this article is to better understand the range of outcomes associated with DSV during youth and adolescence. This systematic review consists of 28 school-based studies from 20 journals discussing outcomes of youth experiences of DSV. Results demonstrate significant associations between DSV victimization and mental health symptoms, substance use, sexual health, academic, and social outcomes. To better understand this issue, this article recommends that schools offer additional training for staff on recognizing DSV. Additionally, improved research is needed in this area including surveys that are inclusive of diverse student identities and include more comprehensive measures of DSV, and additional research on DSV explicitly focused on minoritized groups.

12.
Cardiovasc Diabetol ; 22(1): 346, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38093283

RESUMO

BACKGROUND: This study aimed to evaluate the association of triglyceride-glucose (TyG) index, an insulin resistance surrogate biomarker, with first stroke in a hypertensive population and to explore potential influencing factors. METHODS: This study, a cohort study among a rural Chinese hypertensive population, utilized data from the China Stroke Primary Prevention Trial (CSPPT). The TyG index was calculated as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. Multivariate analysis using Cox proportional hazards models was conducted. RESULTS: A total of 7569 hypertensive patients were included in this study. When TyG index was assessed as quartiles, compared with the reference group (Quartile 1), the hazard ratio of stroke was 1.04 in Quartile 2, 1.43 in Quartile 3, and 1.45 in Quartile 4, with a significant trend test (P = 0.013). When Quartiles 3 and 4 were combined (≥ 8.8), the hazard ratio was 1.41 compared with combined Quartiles 1 and 2 (< 8.8). Similar findings were observed for the association of TyG index with ischemic stroke. Further, a joint effect of baseline TyG index and age on first stroke was found. Using the group with TyG < 8.8 and age < 60 years as a reference, the highest hazard ratio of stroke was found in the group with a higher TyG index and aged 60 or greater (HR: 2.15, 95% CI 1.50, 3.07, P < 0.001). CONCLUSIONS: In a hypertensive population, baseline TyG index was associated with a significantly higher risk of first stroke. In addition, age was a significant effect modifier for this association.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Estudos de Coortes , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Glucose , Triglicerídeos , Glicemia , Fatores de Risco , Biomarcadores
13.
PeerJ ; 11: e16540, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111660

RESUMO

Background: Little is known about the relationship between sleep quality and lung cancer incidence. Thus, this study was conducted to investigate the potential connection between sleep quality and lung cancer incidence. Methods: We performed and selected a nested case-control study that included 150 lung cancer cases and 150 matched controls based on the Lianyungang cohort. Univariate and multivariate logistic regression was utilized to investigate the connection between potential risk factors and lung cancer incidence risk. Results: In this study, the average age of participants was 66.5 ± 9.1 years, with 58.7% being male, and 52.7% reportedly experiencing sleep quality problems. The results of multivariate logistic regression showed that poor sleep quality was connected to an increased lung cancer incidence risk (P = 0.033, odds ratio = 1.83, 95% confidence interval = [1.05-3.19]) compared with those with good sleep quality. The stratified analyses showed a significantly positive connection between poor sleep quality (vs. good sleep quality) and cancer risk in smokers (vs. non-smoker, P for interaction = 0.085). The combined effect analysis indicated that smokers with poor sleep quality suffered from a 2.79-fold increase in cancer incidence rates when compared with non-smokers with good sleep quality. Conclusions: Poor sleep quality was positively connected to an increased lung cancer incidence risk. In addition, among those individuals with poor sleep quality, smoking increased the lung cancer incidence risk.


Assuntos
Neoplasias Pulmonares , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Neoplasias Pulmonares/epidemiologia , Estudos de Casos e Controles , Qualidade do Sono , Fatores de Risco , Fumar/efeitos adversos
14.
Int J Mol Sci ; 24(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37958500

RESUMO

Galectin-3 is the most studied member of the Galectin family, with a large range of mediation in biological activities such as cell growth, proliferation, apoptosis, differentiation, cell adhesion, and tissue repair, as well as in pathological processes such as inflammation, tissue fibrosis, and angiogenesis. As is known to all, inflammation, aberrant cell apoptosis, and neovascularization are the main pathophysiological processes in retinal degeneration and many ocular diseases. Therefore, the review aims to conclude the role of Gal3 in the retinal degeneration of various diseases as well as the occurrence and development of the diseases and discuss its molecular mechanisms according to research in systemic diseases. At the same time, we summarized the predictive role of Gal3 as a biomarker and the clinical application of its inhibitors to discuss the possibility of Gal3 as a novel target for the treatment of ocular diseases.


Assuntos
Galectina 3 , Degeneração Retiniana , Humanos , Galectina 3/genética , Degeneração Retiniana/tratamento farmacológico , Galectinas , Biomarcadores , Inflamação
15.
Sci Rep ; 13(1): 19946, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968276

RESUMO

To investigate the fluorescein angiography (FA) findings and compare the extent of retinal vascularization in retinopathy of prematurity (ROP), recovered after intravitreal ranibizumab (IVR) monotherapy and those regressed spontaneously. Infants with a history of ROP who underwent FA between April 2018 and November 2021 were retrospectively included. The patients were divided into two groups based on whether they had received IVR (IVR group) or had ROP that regressed spontaneously without treatment (untreated group). The differences between the two groups in zone II ROP were also compared, to equalize the subgroups as much as possible in terms of disease severity. FA findings were recorded. The extent of vascularization was measured by the ratio of the distance from the center of the disk to the border of the vascularized zone (DB) and the distance from the center of the disk to the center of the fovea (DF). The width of the persistent avascular retina (PAR) was counted by disc diameters (DD). One hundred and ten eyes of 55 infants were included in the IVR group and 76 eyes of 38 babies in the untreated group. The ratio of abnormal shape of vessels was significantly higher in the IVR group than in the untreated group (50.9% vs. 35.5%; P = 0.038), while the linear choroidal filling pattern, tortuosity of vessels over the posterior pole, dye leakage, anomalous branching of vessels, circumferential vessels, arteriovenous shunt, abnormal capillary bed, and macular abnormalities were similarly. There was a smaller temporal DB/DF ratio (4.48 vs. 4.63; P = 0.003) and greater PAR (2.63 vs. 1.76; P < 0.001) in the IVR group compared to the untreated group. In zone II ROP, the progression of retinal vascularization was significantly larger in the IVR group than that in the untreated group (P = 0.003), while no statistical differences were observed in FA features, the DB/DF ratio, and PAR between the two subgroups. The residual vascular abnormalities and PAR may be common results of ROP regression. The DB/DF ratio of 4.0 temporally and 3.3 nasally could be used as the preliminary indicators for safe retinal vascularization in the completion of ROP regression.


Assuntos
Neovascularização Retiniana , Retinopatia da Prematuridade , Recém-Nascido , Lactente , Humanos , Ranibizumab/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Retinopatia da Prematuridade/diagnóstico por imagem , Retinopatia da Prematuridade/tratamento farmacológico , Recém-Nascido Prematuro , Estudos Retrospectivos , Angiofluoresceinografia/métodos , Injeções Intravítreas , Diálise Renal , Neovascularização Retiniana/diagnóstico por imagem , Neovascularização Retiniana/tratamento farmacológico , Idade Gestacional
16.
Antioxidants (Basel) ; 12(11)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38001832

RESUMO

The outer blood-retina barrier (oBRB), comprises tightly connected retinal pigment epithelium (RPE) cells, Bruch's membrane, and choroid blood vessels, and is essential for retinal health and normal visual function. Disruption of the RPE barrier and its dysfunction can lead to retinal disorders such as age-related macular degeneration (AMD). In the present study, we investigated the essential role of choroid endothelial cells (ECs) in the RPE barrier formation process and its dysfunction. We discovered that ECs promoted RPE barrier formation through angiocrine signaling. Through blocking or activating endothelial Notch signaling and conducting experiments in vitro and in vivo, we confirmed that endothelial Notch signaling regulated the expression of heparin-binding epidermal growth factor (HBEGF) and consequently impacted the expression and activity of matrix metalloproteinases (MMP)-9 in RPE cells. This modulation influenced the RPE extracellular matrix deposition, tight junctions and RPE barrier function. In in vivo experiments, the intravitreal administration of recombinant HBEGF (r-HBEGF) alleviated the RPE barrier disruption induced by subretinal injection (SI) or laser treatment and also rescued RPE barrier disruption in endothelial Notch-deficient mice. Our results showed that the endothelial Notch signaling drove HBEGF expression through angiocrine signaling and effectively improved RPE barrier function by regulating the MMP-9 expression in RPE cells. It suggests that the modulation of Notch signaling in the choroidal endothelium may offer a novel therapeutic strategy for retinal degenerative diseases.

17.
Materials (Basel) ; 16(22)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38005135

RESUMO

The oxidation of ß-NiAl at high temperatures leads to the preferential formation of metastable alumina, such as θ-Al2O3, which exhibits a significantly faster growth rate compared to stable α-Al2O3. However, our recent research has shown that through the use of the surface-dispersing nanoparticles (NPs) of metal oxides with a hexagonal closed pack (hcp), such as α-Al2O3, the thermal growth of α-Al2O3 can be facilitated. The present study employed laser additive manufacturing (LAM) to develop an integrated α-Al2O3 NPs surface-seeded two-phase intermetallic alloy comprising brittle ß-NiAl and tougher γ'-Ni3Al, which demonstrated better comprehensive mechanical properties. It was found that seeding the α-Al2O3 NPs promoted the early stage growth of α-Al2O3 on both ß and γ' phases during oxidation in air at 1000 °C. This led to a decrease in the oxidation rate but an enhancement in adhesion of the formed alumina scale in comparison to the naked ß/γ' two-phase alloy. The reasons for this result were interpreted.

18.
Sci Rep ; 13(1): 19069, 2023 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-37925518

RESUMO

Glutamate, the major excitatory neurotransmitter in the central nervous system, has also been found to play a role in embryonic stem (ES) cells. However, the exact mechanism and function of glutamatergic signaling in ES cells remain poorly understood. In this study, we identified a glutamatergic transmission circuit in ES cells that operates through an autocrine mechanism and regulates cell proliferation. We performed biological analyses to identify the key components involved in glutamate biosynthesis, packaging for secretion, reaction, and reuptake in ES cells, including glutaminase, vesicular glutamate transporter, glutamate N-methyl-D-aspartate (NMDA) receptor, and cell membrane excitatory amino-acid transporter (EAAT). We directly quantified the released glutamate signal using microdialysis-high performance liquid chromatography-tandem mass spectrometry (MD-HPLC-MS-MS). Pharmacological inhibition of endogenous glutamate release and the resulting tonic activation of NMDA receptors significantly affected ES cell proliferation, suggesting that ES cells establish a glutamatergic autocrine niche via releasing and responding to the transmitter for their own regulation.


Assuntos
Células-Tronco Embrionárias , Ácido Glutâmico , Ácido Glutâmico/metabolismo , Células-Tronco Embrionárias/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Aminoácidos Excitatórios , Proliferação de Células
19.
Front Nutr ; 10: 1191610, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781132

RESUMO

Background: There is growing concern regarding elevated levels of circulating unmetabolized folic acid (UMFA) due to excessive intake of folic acid (FA). However, no randomized clinical trial has been conducted to examine the FA-UMFA dose-response relationship. Objective: This study aimed to investigate the FA-UMFA dose-response relationship in Chinese adults with hypertension and elevated homocysteine (H-type hypertension), a population with clear clinical indication for FA treatment. Methods: The data for this study were derived from a randomized, double-blind, multicenter clinical trial of 8 FA dosages on efficacy of homocysteine (Hcy) lowering. The parent trial had three 3 stages: screening period (2-10 days), run-in period (0-2 weeks, baseline visit), and double-blind treatment period (8 weeks) with follow-up visits at the end of the 2nd, 4th, 6th, and 8th weeks of treatment. Participants were randomly assigned to 8 treatment groups corresponding to FA dosages of 0, 0.4, 0.6, 0.8, 1.2, 1.6, 2.0 mg to 2.4 mg. Results: This study included 1,567 Chinese adults aged ≥45 years with H-type hypertension. There was a positive but non-linear association between FA supplementation and UMFA levels in the dosage range of 0 mg to 2.4 mg. In the regression analysis, the coefficients for the linear and quadratic terms of FA dosage were both statistically significant (P < 0.001). Notably, the slope for UMFA was greater for FA dosages >0.8 mg (ß = 11.21, 95% CI: 8.97, 13.45) compared to FA dosages ≤0.8 mg (ß = 2.94, 95% CI: 2.59, 3.29). Furthermore, FA dosages higher than 0.8 mg did not confer additional benefits in terms of increasing 5-methyl tetrahydrofolic acid (5-MTHF, active form of folate) or reducing homocysteine (Hcy). Conclusion: In Chinese adults with H-type hypertension, this study showed a positive, non-linear, dosage-response relationship between FA supplementation ranging from 0 to 2.4 mg and circulating UMFA levels. It revealed that 0.8 mg FA is an optimal dosage in terms of balancing efficacy (increasing 5-MTHF and lowering Hcy) while minimizing undesirable elevation of UMFA. Clinical trial registration: https://clinicaltrials.gov/ct2/show/NCT03472508?term=NCT03472508&draw=2&rank=1, identifier NCT03472508.

20.
Obesity (Silver Spring) ; 31(10): 2648-2657, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37724055

RESUMO

OBJECTIVE: The study aim was to investigate associations of 11 anthropometric measures with incident type 2 diabetes and compare their predictive performance. METHODS: This prospective cohort study included 161,127 White European UK Biobank participants who were free of diabetes at baseline. Anthropometric measures included height, weight, BMI, A Body Shape Index, waist circumference, waist to hip ratio, waist to height ratio (WHtR), hip circumference, visceral adiposity index, hip index, and anthropometric risk index. The associations were examined using Cox proportional hazard models. The differences in C-index were used to compare predictive performance between BMI and other anthropometric measures. RESULTS: The median follow-up was 10.0 (interquartile range: 9.3-10.8) years, during which 6315 participants developed type 2 diabetes. All markers except height and hip index were positively associated with incident type 2 diabetes. The strongest associations were found for WHtR (hazard ratio per 1-SD increment: 2.27 [95% CI 2.19-2.35] in women; 1.96 [95% CI 1.90-2.01] in men). Compared with BMI, WHtR and anthropometric risk index had significantly better type 2 diabetes risk discrimination. CONCLUSIONS: Although most adiposity markers were associated with type 2 diabetes, the magnitude of the associations differed. WHtR had the strongest associations and predictive ability for type 2 diabetes and thus could be a more suitable marker for clinical use.


Assuntos
Diabetes Mellitus Tipo 2 , Masculino , Humanos , Feminino , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Bancos de Espécimes Biológicos , Estudos Prospectivos , Adiposidade , Reino Unido/epidemiologia
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