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1.
Small Methods ; 5(3): e2000777, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34927816

RESUMO

The assembly of gigantic heterometallic metal clusters remains a great challenge for synthetic chemistry. Herein, based on the slow release strategy of lanthanide ions and in situ formation of lacunary polyoxometalates, two giant 3d-4f polyoxometalate inorganic clusters [LaNi12 W35 Sb3 P3 O139 (OH)6 ]23- (LaNi12 ) and [La10 Ni48 W140 Sb16 P12 O568 (OH)24 (H2 O)20 ]86- (La10 Ni48 ) are obtained. The nanoscopic inorganic cluster La10 Ni48 possesses a super tetrahedron structure, which can be viewed as assembly from four LaNi12 molecules encapsulating a central [La6 (SbO3 )4 (H2 O)20 ]6+ octahedron core. This giant aesthetic La10 Ni48 tetrahedron containing 214 metal ions is the largest 3d-4f cluster reported thus far in polyoxometalate system. More interestingly, the LaNi12 and La10 Ni48 display high stability in solution and La10 Ni48 displays excellent proton conductivity.

2.
JAMA Netw Open ; 4(12): e2141498, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34967878

RESUMO

Importance: The associations of gestational weight gain (GWG) with infant morbidity and mortality are unclear, and the existing recommendations for GWG have not been stratified by the severity of obesity. Objectives: To identify optimal GWG ranges associated with reduced risks of infant morbidity and mortality across maternal body mass index (BMI) categories. Design, Setting, and Participants: This retrospective cohort study used US nationwide, linked birth and infant death data between 2011 and 2015 to assess the associations of GWG in 2.0-kg groups with infant morbidity and mortality and identified optimal GWG ranges associated with reduced risks of both outcomes, using multivariable logistic regression models. Statistical analysis was performed from February 11 to October 14, 2021. Exposure: Gestational weight gain equivalent to 40 weeks. Main Outcomes and Measures: The 2 main outcomes were (1) significant morbidity of the newborn infant, defined as any presence of assisted ventilation, admission to the neonatal intensive care unit, surfactant therapy, antibiotic therapy, or seizures; and (2) infant mortality younger than 1 year of age (<1 hour, 1-23 hours, 1-6 days, 7-27 days, or 28-365 days after birth). Results: In this study of 15 759 945 mother-infant dyads, the mean (SD) age of the women was 28.1 (5.9) years. Women gained a mean (SD) of 14.1 (7.3) kg during pregnancy, and the mean (SD) GWG decreased with BMI categories (underweight, 15.7 [6.4] kg; normal weight, 15.4 [6.2] kg; overweight, 14.2 [7.4] kg; obesity class 1, 12.2 [8.0] kg; obesity class 2, 10.3 [8.4] kg; obesity class 3, 8.2 [9.2] kg; P < .001). A total of 8.8% of the newborns experienced significant morbidity, with the lowest prevalence among infants delivered by women in the normal weight BMI class (8.0%) and the highest among infants delivered by women with class 3 obesity (12.4%); 0.34% of infants died within 1 year of birth, with the lowest prevalence among infants delivered by women in the normal weight BMI class (0.28%) and the highest among infants delivered by women with class 3 obesity (0.58%). Optimal GWG ranges were 12.0 to less than 24.0 kg for underweight and normal weight women, 10.0 to less than 20.0 kg for overweight women, 8.0 to less than 16.0 kg for women with class 1 obesity, 6.0 to less than 16.0 kg for class 2 obesity, and 6.0 to less than 10.0 kg for class 3 obesity. The lower bounds of the optimal GWG ranges appeared to be higher than the existing recommendations for overweight women (10.0 vs 7.0 kg) and for those with class 1 (8.0 vs 5.0 kg), class 2 (6.0 vs 5.0 kg), and class 3 (6.0 vs 5.0 kg) obesity. Conclusions and Relevance: This study analyzed the associations of GWG with infant morbidity and mortality across BMI categories and found that inadequate GWG was associated with increased risks of adverse infant outcomes even for women with obesity. The results suggested that weight maintenance or weight loss should not be used as routine guidelines.


Assuntos
Ganho de Peso na Gestação , Mortalidade Infantil/tendências , Obesidade , Complicações na Gravidez , Adulto , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Resultado da Gravidez , Cuidado Pré-Natal , Estudos Retrospectivos , Fatores de Risco , Estados Unidos/epidemiologia
3.
Nat Cell Biol ; 23(11): 1136-1147, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34750583

RESUMO

The development of a functional vasculature requires the coordinated control of cell fate, lineage differentiation and network growth. Cellular proliferation is spatiotemporally regulated in developing vessels, but how this is orchestrated in different lineages is unknown. Here, using a zebrafish genetic screen for lymphatic-deficient mutants, we uncover a mutant for the RNA helicase Ddx21. Ddx21 cell-autonomously regulates lymphatic vessel development. An established regulator of ribosomal RNA synthesis and ribosome biogenesis, Ddx21 is enriched in sprouting venous endothelial cells in response to Vegfc-Flt4 signalling. Ddx21 function is essential for Vegfc-Flt4-driven endothelial cell proliferation. In the absence of Ddx21, endothelial cells show reduced ribosome biogenesis, p53 and p21 upregulation and cell cycle arrest that blocks lymphangiogenesis. Thus, Ddx21 coordinates the lymphatic endothelial cell response to Vegfc-Flt4 signalling by balancing ribosome biogenesis and p53 function. This mechanism may be targetable in diseases of excessive lymphangiogenesis such as cancer metastasis or lymphatic malformation.

4.
J Neurol ; 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34731309

RESUMO

Aneurysm wall permeability has recently emerged as an in vivo marker of aneurysm wall remodeling. We sought to study the spatial relationship between hemodynamic forces derived from 4D-flow MRI and aneurysm wall permeability by DCE-MRI in a region-based analysis of unruptured saccular intracranial aneurysms (IAs). We performed 4D-flow MRI and DCE-MRI on patients with unruptured IAs of ≥ 5 mm to measure hemodynamic parameters, including wall shear stress (WSS), oscillatory shear index (OSI), WSS temporal (WSSGt) and spatial (WSSGs) gradient, and aneurysm wall permeability (Ktrans) in different sectors of aneurysm wall defined by evenly distributed radial lines emitted from the aneurysm center. The spatial association between Ktrans and hemodynamic parameters measured at the sector level was evaluated. Thirty-one patients were scanned. Ktrans not only varied between aneurysms but also demonstrated spatial heterogeneity within an aneurysm. Among all 159 sectors, higher Ktrans was associated with lower WSS, which was seen in both Spearman's correlation analysis (rho = - 0.18, p = 0.025) and linear regression analysis using generalized estimating equation to account for correlations between multiple sectors of the same aneurysm (regression coefficient = - 0.33, p = 0.006). Aneurysm wall permeability by DCE-MRI was shown to be spatially heterogenous in unruptured saccular IAs and associated with local WSS by 4D-flow MRI.

5.
Small ; 17(45): e2104144, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34605170

RESUMO

Perovskite-based oxides attract great attention as catalysts for energy and environmental devices. Nanostructure engineering is demonstrated as an effective approach for improving the catalytic activity of the materials. The mechanism for the enhancement, nevertheless, is still not fully understood. In this study, it is demonstrated that compressive strain can be introduced into freestanding perovskite cobaltite La0.8 Sr0.2 CoO3- δ (LSC) nanofibers with sufficient small size. Crystal structure analysis suggests that the LSC fiber is characterized by compressive strain along the ab plane and less distorted CoO6 octahedron compared to the bulk powder sample. Accompanied by such structural changes, the nanofiber shows significantly higher oxygen reduction reaction (ORR) activity and better stability at elevated temperature, which is attributed to the higher oxygen vacancy concentration and suppressed Sr segregation in the LSC nanofibers. First-principle calculations further suggest that the compressive strain in LSC nanofibers effectively shortens the distance between the Co 3d and O 2p band center and lowers the oxygen vacancy formation energy. The results clarify the critical role of surface stress in determining the intrinsic activity of perovskite oxide nanomaterials. The results of this work can help guide the design of highly active and durable perovskite catalysts via nanostructure engineering.

6.
Int J Obes (Lond) ; 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34628467

RESUMO

OBJECTIVE: To investigate the impact of body mass index (BMI) on the success rate and prenatal outcomes of fresh embryo transfer in women undergoing their first in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment. METHODS: It is a post-hoc analysis of a prospective observational cohort study. 2569 Chinese women were grouped in quintiles of BMI and according to the official Chinese classification of body weight. IVF/ICSI and pregnancy outcomes were compared between groups. RESULTS: BMI was not associated with IVF/ICSI pregnancy outcomes including hCG positive rate, clinical pregnancy rate, implantation rate, ectopic pregnancy rate, ongoing pregnancy rate, early miscarriage rate, and live birth rate. However, it was negatively related to some pregnancy complications such as gestational diabetes mellitus (GDM) and hypertension. Additionally, the proportion of Cesarean-section was increased with BMI. As for prenatal outcomes, the current results showed no statistical difference in the number of male and female newborn, the proportion of low live birth weight (<2500 g), macrosomia (≥4000 g) (both in all live birth and full-term live birth), and premature delivery (<37 weeks). CONCLUSIONS: The current study showed that BMI was not associated with embryo transfer outcomes after fresh embryo transfer in women undergoing their first IVF/ICSI treatment, whereas BMI was associated with GDM and gestational hypertension.

7.
Adv Sci (Weinh) ; 8(22): e2102713, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34658158

RESUMO

Doping perovskite oxide with different cations is used to improve its electro-catalytic performance for various energy and environment devices. In this work, an activated lattice oxygen activity in Pr0.4 Sr0.6 Cox Fe0.9- x Nb0.1 O3- δ (PSCxFN, x = 0, 0.2, 0.7) thin film model system by B-site cation doping is reported. As Co doping level increases, PSCxFN thin films exhibit higher concentration of oxygen vacancies ( V o • • ) as revealed by X-ray diffraction and synchrotron-based X-ray photoelectron spectroscopy. Density functional theory calculation results suggest that Co doping leads to more distortion in FeO octahedra and weaker metaloxygen bonds caused by the increase of antibonding state, thereby lowering V o • • formation energy. As a consequence, PSCxFN thin film with higher Co-doping level presents larger amount of exsolved particles on the surface. Both the facilitated V o • • formation and B-site cation exsolution lead to the enhanced hydrogen oxidation reaction (HOR) activity. Excessive Co doping until 70%, nevertheless, results in partial decomposition of thin film and degrades the stability. Pr0.4 Sr0.6 (Co0.2 Fe0.7 Nb0.1 )O3 with moderate Co doping level displays both good HOR activity and stability. This work clarifies the critical role of B-site cation doping in determining the V o • • formation process, the surface activity, and structure stability of perovskite oxides.

9.
J Reprod Immunol ; 147: 103362, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34482188

RESUMO

Many factors impede embryonic implantation, and excluding obvious known factors such as chronic endometritis, the immune status of the endometrium may be related to pregnancy. Although an abundantly large number of immune cells infiltrate the endometrium during the secretory phase, whether these immune cells can be used as a predictor of prognosis in ART has not yet been clarified. In the present study we therefore retrospectively analyzed 97 CD138-negative women with a previous fresh-embryo-transfer failure. We assessed the expression of CD56+ uNK cells, CD16+ NK cells, CD57+ NK cells, CD68+ pan-macrophages, CD163+ M2 macrophages, CD4+T cells, CD8+T cells, FOXP3+ regulatory T cells, and CD19+ B cells in the endometrium by IHC to evaluate mid-luteal endometrial immune cells as prognostic indicators of pregnancy outcome in the next frozen-embryo-transfer cycle. CD19-positive cells and the intraglandular CD163-positivity rate increased significantly in the clinically non-pregnant group (0.47 % vs. 0.20 %, P = 0.021; 61 % vs. 30 %, P = 0.017). The ratios of CD4/CD8 were also higher in the non-pregnant group (1.96 vs. 1.45, P = 0.005).The area under the ROC curve of CD19 cell number alone, the intraglandular CD163-positivity alone, and CD19 number combined with the intraglandular CD163-positivity were 0.692 (95 % CI, 0.55-0.834), 0.661 (95 % CI, 0.514-0.809), and 0.748 (95 % CI, 0.614-0.882), respectively. The optimal cut-off value of CD19 was 0.464 %, and the clinical pregnancy rate and live-birth rate diminished significantly when the CD19 level was above this cut-off value. Our study suggests that CD19-positive cells and intraglandular CD163-positivity can be used as prognostic indicators of pregnancy outcome in CD138-negative patients who experienced first-fresh-embryo transfer failure.

10.
Transplant Proc ; 53(8): 2503-2508, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482997

RESUMO

BACKGROUND: Patients with early-stage renal cell carcinoma (RCC) are considered to be eligible donors. Although preliminary experience in using kidneys of specific pathologic types, mainly those with small renal masses (SRMs), have been established, multiorgan utilization of the same donor with SRMs is limited. METHODS: One deceased donor whose left-side kidney was diagnosed with Fuhrman grade I RCC was included. The tumor mass in the kidney was removed through partial nephrectomy according to the gold standard. Then, 3 transplant surgeries were performed, in which 1 recipient accepted kidney transplant after tumor exeresis, 1 simultaneous heart-kidney (the contralateral one) transplant, and 1 liver transplant. Recipients were followed up according to our standard protocol for renal cancers. (All allografts were allocated in compliance with the Declaration of Helsinki and the Declaration of Istanbul.) RESULTS: After 32 months, no radiographic findings showed any morphologic changes of the lesion, and all patients were in good condition, with neither tumor recurrence nor allograft rejection or infection. No complaints such as pain, oliguria, dyspnea, nausea, or fatigue were recorded. CONCLUSIONS: To the best of knowledge, this initial work takes the lead in elaborating the organ utilization of multiorgan donors with SRMs. We hope the experience will provide support for cross discussion concerned with multiorgan transplant from tumor-affected donors in clinical practices, further expand the donor pool and address the donor shortage problem.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Transplante de Rim , Carcinoma de Células Renais/cirurgia , Sobrevivência de Enxerto , Humanos , Neoplasias Renais/cirurgia , Transplante de Rim/efeitos adversos , Recidiva Local de Neoplasia , Doadores de Tecidos
11.
Artigo em Inglês | MEDLINE | ID: mdl-34415990

RESUMO

BACKGROUND: The risk of developing gestational diabetes mellitus (GDM) is higher in women undergoing assisted reproductive treatment than in women conceiving spontaneously. OBJECTIVES: To determine whether the GDM risk after day-3 embryo transfer differs from the GDM risk after day-5 blastocyst transfer. METHODS: Prospective observational study in women becoming pregnant after first fresh embryo or blastocyst transfer. RESULTS: 1579 women got pregnant and had life birth. 1300 women got day three embryo transfer only, whereas 279 women received at least one blastocyst. 252 out of the 1579 women developed GDM. Age, body mass index, baseline estradiol, baseline high-density lipoprotein, and progesterone on the day of hCG injection were not different in women receiving day three embryos only versus women receiving at least one blastocyst. The number and quality of retrieved oocytes were not different in women receiving day 3 embryo transfer (ET) from those receiving blastocysts. Our study confirmed already established GDM risk factors such as age and body mass index, baseline estradiol and high-density lipoprotein, as well as progesterone after ovarian stimulation. We could furthermore demonstrate that the GDM incidence in women receiving day five blastocyst transfer was significantly higher than those who received day three embryo transfer (21.15% vs. 14.85%, P=.009). Considering confounding factors, we likewise saw that blastocyst transfer was an independent procedure-related GDM risk factor (P = 0.009, Exp (B): 1.56, 95% CI: 1.12-2.18). CONCLUSION: Blastocyst transfer after IVF/ICSI increases the risk of developing GDM.

12.
PLoS One ; 16(8): e0256263, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34398930

RESUMO

BACKGROUND AND PURPOSE: Several studies have evaluated the effects of high-intensity aerobic training (HIAT) on pain severity and quality of life (QoL) among women with primary dysmenorrhea. However, to date, no studies have evaluated the effectiveness of HIAT on academic performance or absenteeism or examined the cost-effectiveness of HIAT relative to other treatments in women with primary dysmenorrhea. Furthermore, the mechanisms underlying aerobic exercise-induced analgesia in primary dysmenorrhea remain unclear. The objectives of this study are to: (1) evaluate the effects of HIAT on absenteeism and academic performance among university students, (2) identify the underlying mechanisms associated with aerobic exercise-induced analgesia in primary dysmenorrhea, and (3) determine the cost-effectiveness of HIAT compared with a wait-list control (WLC) group receiving usual care. METHODS: A sequential, embedded, mixed-methods study design, including a crossover, randomised controlled trial (RCT) and semi-structured focus groups, will be conducted alongside an economic evaluation. A total of 130 women aged 18-24 years will be randomised into either HIAT (n = 65) or wait-list control (n = 65) groups. Primary outcomes will include average pain intensity, absenteeism from university, and academic performance. Primary mediators will include salivary progesterone and prostaglandin F2α levels. Outcome and meditator variables will be assessed at baseline and post-treatment, at 12 and 28 weeks. An economic analysis will be conducted from the societal and healthcare perspective of Hong Kong. Semi-structured focus groups will be conducted at 32 weeks. Of the 130 participants included in the RCT, 70 will be included in the focus groups. STATISTICAL ANALYSIS: All statistical analyses will be performed on an intention-to-treat basis, using SPSS (version 24). Preliminary analysis using an independent samples t-test and a two-sided, unpaired Student's t-test will be performed to exclude carryover effects and identify within-participant differences in outcome variables between the study periods, respectively. Treatment effects will be evaluated using analysis of variance via a mixed-effects model with fixed effects for intervention, period, and sequence. In all models, random effects will include the participants nested within the sequence as a sampling cluster. The mediation effects will be assessed using the Sobel test. The EQ-5D responses will be converted into utility scores to estimate the gain or loss of quality-adjusted life-years. Seemingly unrelated regression analyses will be used to estimate the total cost differences and effect differences. Qualitative data will be analysed using the process of thematic analysis.

13.
Pharmaceuticals (Basel) ; 14(7)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206901

RESUMO

Lymphangiogenesis, the formation of new lymphatic vessels from pre-existing vasculature, plays critical roles in disease, including in cancer metastasis and chronic inflammation. Preclinical and recent clinical studies have now demonstrated therapeutic utility for several anti-lymphangiogenic agents, but optimal agents and efficacy in different settings remain to be determined. We tested the anti-lymphangiogenic property of 3,4-Difluorobenzocurcumin (CDF), which has previously been implicated as an anti-cancer agent, using zebrafish embryos and cultured vascular endothelial cells. We used transgenic zebrafish labelling the lymphatic system and found that CDF potently inhibits lymphangiogenesis during embryonic development. We also found that the parent compound, Curcumin, does not inhibit lymphangiogenesis. CDF blocked lymphatic and venous sprouting, and lymphatic migration in the head and trunk of the embryo. Mechanistically, CDF impaired VEGFC-VEGFR3-ERK signalling in vitro and in vivo. In an in vivo pathological model of Vegfc-overexpression, treatment with CDF rescued endothelial cell hyperplasia. CDF did not inhibit the kinase activity of VEGFR3 yet displayed more prolonged activity in vivo than previously reported kinase inhibitors. These findings warrant further assessment of CDF and its mode of action as a candidate for use in metastasis and diseases of aberrant lymphangiogenesis.

14.
Can J Physiol Pharmacol ; 99(9): 857-863, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34143694

RESUMO

The present study aims to explore the role of microRNA 145-5p (miR-145-5p) in hyperlipidemia. Using bioinformatics tools and a wide range of function and mechanism assays, we attempted to understand the specific function and potential mechanism of miR-145-5p in hyperlipidemia. A cholesterol-enriched diet induced an increase of serum cholesterol and triacylglycerol but a decrease of serum high-density lipoprotein. MiR-145-5p level was decreased in hyperlipidemia rat models. MiR-145-5p regulated lipid metabolism by antagonizing the alteration of high-density lipoprotein, cholesterol, and triacylglycerol in serum mediated by a cholesterol-enriched diet. In mechanism, miR-145-5p directly bound with p21 protein (RAC1)-activated kinase 7 (PAK7) and negatively regulated mRNA and protein levels of PAK7 in THP-1 cells. Furthermore, miR-145-5p level was negatively associated with PAK7 level in rat cardiac tissues. Finally, overexpression of PAK7 reversed the effects of miR-145-5p on ß-catenin activation and M2 macrophages polarization in THP-1 cells. In conclusion, MiR-145-5p modulated lipid metabolism and M2 macrophage polarization by targeting PAK7 and regulating ß-catenin signaling in hyperlipidemia, which may provide a potential biomarker for the treatment of hyperlipidemia-induced cardiovascular diseases.

15.
Tissue Eng Part A ; 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34128385

RESUMO

With the expected rise in patients undergoing refractive lenticule extraction worldwide, the number of discarded corneal stromal lenticules will increase. Therefore, establishing a lenticule bank to collect, catalog, process, cryopreserve, and distribute the lenticules (for future therapeutic needs) could be advantageous. In this study, we validated the safety of lenticule banking that involved the collection of human lenticules from our eye clinic, transportation of the lenticules to a Singapore Ministry of Health-licensed lenticule bank, processing, and cryopreservation of the lenticules, which, after 3 months or, a longer term, 12 months, were retrieved and transported to our laboratory for implantation in rabbit corneas. The lenticule collection was approved by the SingHealth Centralised Institutional Review Board (CIRB). Both short-term and long-term cryopreserved lenticules, although not as transparent as fresh lenticules due to an altered collagen fibrillar packing, did not show any sign of rejection and cytotoxicity, and did not induce haze or neovascularization for 16 weeks even when antibiotic and steroidal administration were withdrawn after 8 weeks. The lenticular transparency progressively improved and was mostly clear after 4 weeks, the same period when we observed the stabilization of corneal hydration. We showed that the equalization of the collagen fibrillar packing of the lenticules with that of the host corneal stroma contributed to the lenticular haze clearance. Most importantly, no active wound healing and inflammatory reactions were seen after 16 weeks. Our study suggests that long-term lenticule banking is a feasible approach for the storage of stromal lenticules after refractive surgery.

16.
J Nutr ; 151(9): 2835-2842, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34191031

RESUMO

BACKGROUND: Brain iron accumulation is a feature of Alzheimer disease (AD) but whether a chronic dietary iron overload contributes to AD induction is unknown. We previously showed that young mice fed a high iron diet did not display cognitive impairment despite the AD pathological markers in hippocampus. OBJECTIVES: We aim to compare the impact of high dietary iron on brain pathologic changes and cognitive function in young and old mice. METHODS: Male C57BL/6J mice at 1 mo and 13 mo of age were fed with either a control diet (66 mg Fe/kg; Young-Ctrl and Old-Ctrl) or a high iron diet (14 g Fe/kg; Young-High Fe and Old-High Fe) for 7 mo, and outcomes were evaluated at 8 mo and 20 mo of age. Iron concentrations in brain regions were measured by atomic absorption spectrophotometry. Perls's Prussian blue staining and amyloid-ß (Aß) immunostaining were performed. Protein expression in the cerebral cortex and hippocampus was determined by immunoblotting. Superoxide dismutase activity and malondialdehyde concentration were examined. Cognitive functions were tested with the Morris water maze system. Two-factor ANOVA was used to analyze most data. RESULTS: Compared with Old-Ctrl mice, Old-High Fe mice showed significantly higher iron concentrations in cerebral cortex (60% higher), cerebellum (60% higher), and hippocampus (90% higher), paralleled by lower superoxide dismutase activity and greater malondialdehyde concentration in cerebral cortex and hippocampus and worse cognitive function. In contrast, these variables did not significantly differ between the 2 young groups. Nevertheless, ferritin, phospho-tau, and Aß1-42 expression in hippocampus and ferritin and Aß1-42 expression in cerebral cortex were induced by the high iron diet irrespective of the age of mice (40-200% greater). CONCLUSIONS: High dietary iron induced cognitive defects in old mice but not young mice, suggesting that elderly people should avoid consuming abnormally high concentrations of iron.

17.
Elife ; 102021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34003110

RESUMO

The formation of new blood vessel networks occurs via angiogenesis during development, tissue repair, and disease. Angiogenesis is regulated by intracellular endothelial signalling pathways, induced downstream of vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs). A major challenge in understanding angiogenesis is interpreting how signalling events occur dynamically within endothelial cell populations during sprouting, proliferation, and migration. Extracellular signal-regulated kinase (Erk) is a central downstream effector of Vegf-signalling and reports the signalling that drives angiogenesis. We generated a vascular Erk biosensor transgenic line in zebrafish using a kinase translocation reporter that allows live-imaging of Erk-signalling dynamics. We demonstrate the utility of this line to live-image Erk activity during physiologically relevant angiogenic events. Further, we reveal dynamic and sequential endothelial cell Erk-signalling events following blood vessel wounding. Initial signalling is dependent upon Ca2+ in the earliest responding endothelial cells, but is independent of Vegfr-signalling and local inflammation. The sustained regenerative response, however, involves a Vegfr-dependent mechanism that initiates concomitantly with the wound inflammatory response. This work reveals a highly dynamic sequence of signalling events in regenerative angiogenesis and validates a new resource for the study of vascular Erk-signalling in real-time.


Assuntos
Células Endoteliais/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Sistema de Sinalização das MAP Quinases/fisiologia , Neovascularização Patológica/metabolismo , Neovascularização Fisiológica , Transdução de Sinais , Animais , Células Cultivadas , Sistema de Sinalização das MAP Quinases/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Peixe-Zebra
18.
Inorg Chem ; 60(10): 6986-6990, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33913715

RESUMO

Multifunctional lanthanide coordination polymers (CPs) have the advantages of acting in two or more fields simultaneously. Herein, two single lanthanide CPs, formulated as LnL(D/L-Hlac)(H2O)2·0.5H2O (Ln = Eu (1), Tb (2); H2L = 4,4'-(pyridine-3,5-diyl)dibenzoic acid) and their doped lanthanide analogue Tb0.9373Eu0.0627L(D/L-Hlac)(H2O)2·0.5H2O (3) were prepared through hydrothermal methods. Luminescence measurements reveal that 1 displays red photoluminescence and its Commission International ed'Eclairage (CIE) coordinates are almost invariant in the temperature range from 80 to 300 K, while the emission color of 2 changes from yellow to green and its CIE coordinates change from (0.36132, 0.56365) at 80 K to (0.30448, 0.45566) at 300 K. Significantly, 3 not only displays white-light emission with CIE coordinates of (0.32999, 0.33406) but also exhibits a thermal sensitivity of 2.27% K-1 at 230-300 K. The obviously larger thermal sensitivity in 3 in comparison to that of 1.07% K-1 for 2 demonstrates that lanthanide CPs with both a heat-sensitive fluorescent thermometer and high-efficiency white-light emission can be expected by doping Eu(III) ions into Tb(III)-based CPs.

19.
Inorg Chem ; 60(10): 6981-6985, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33913721

RESUMO

Four pairs of chiral 3D coordination polymers (CPs), [Zn2(BDC)(lac)(DMF)]·guest (2) (H2BDC = benzene dicarboxylic acid; H2lac = lactic acid; guest = 1.5DMF + i-PrOH), [Co2(BDC)(lac)(DMF)]·guest (3) (guest = DMF + 2H2O), [Fe4(BDC)3(lac)2(DMF)2](CO3)·guest (4) (guest = DMF + 2H2O), and {Zn11(BPDC)6(lac)6[NH2(CH3)2]2}·guest (H2BPDC = 3,3'-biphenyldicarboxylic acid; guest = 6DMF + 18H2O) (5), are prepared through the reactions of racemic lactic acid (rac-H2lac) with different metal ions and auxiliary ligands. Structural analyses and DFT calculations reveal that forming more and stronger coordination bonds between the auxiliary ligand and metal ions is more conducive to the spontaneous resolution of enantiomers in 3D CPs than simply increasing the entropy of the auxiliary ligand itself.

20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(2): 525-529, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33812425

RESUMO

OBJECTIVE: To investigate the expression of HSP90 in bone marrow samples of multiple myeloma (MM) patients and explore its clinical significance. METHODS: Maxvision immunohistochemistry technique was used to detect the protein expression level of HSP90 76 MM patients and 29 normal healthy donors. The clinical characteristics of the patients were collected, and the correlation between the HSP90 expression and the clinical characteristics was analyzed. RESULTS: The count of MM patients with positive HSP90 protein was significantly higher than that of normal healthy donor, and there were no significant correlation between HSP90 expression and age, sex, hemoglobin (Hb), creatinine (CREA), blood calcium, lactate dehydrogenase (LDH), bone marrow plasma cell proportion and MM subtypes (P>0.05), but HSP90 expression was correlated with ß2-microglobulin (ß2-MG) and ISS stage (P<0.05). The survival time was lower in MM patients with high expression HSP90 as compared with low expression HSP90 MM patients. CONCLUSION: HSP90 protein was over-expressed in MM patients, and was correlated with ß2-microglobulin, ISS stage and OS of MM patients.


Assuntos
Mieloma Múltiplo , Medula Óssea , Proteínas de Choque Térmico HSP90 , Humanos , Prognóstico , Microglobulina beta-2
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