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1.
J Magn Reson Imaging ; 54(1): 263-272, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33559371

RESUMO

BACKGROUND: Several published studies have shown alterations of brain development in third-trimester fetuses with congenital heart disease (CHD). However, little is known about the timing and pattern of altered brain development in fetuses with CHD. PURPOSE: To investigate the changes in the volume of intracranial structures in fetuses with CHD by three-dimensional (3D) volumetric magnetic resonance imaging (MRI) in the earlier stages of pregnancy (median gestational age [GA], 26 weeks). STUDY TYPE: Retrospective. POPULATION: Forty women carrying a fetus with CHD (including 20 fetuses with GA <26 weeks) and 120 pregnant women carrying a healthy fetus (including 50 fetuses with GA <26 weeks). FIELD STRENGTH/SEQUENCE: Two-dimensional single-shot turbo spin echo sequence at 1.5 -T. ASSESSMENT: Three-dimensional volumetric parameters from slice-to-volume registered images, including cortical gray matter volume (GMV), subcortical brain tissue volume (SBV), intracranial cavity volume (ICV), lateral ventricles volume (VV), cerebellum, brainstem, and extra-cerebrospinal fluid (e-CSF) were quantified by manual segmentation from one primary and two secondary observers. STATISTICAL TESTS: Volumes were presented graphically with quadratic curve fitting. Scatterplots were produced mapping volumes against GA in normal and CHD fetuses. For GA <26 weeks, Z scores were calculated and Student's t-tests were conducted to compare volumes between the normal and CHD fetuses. RESULTS: In fetuses with CHD GMV, SBV, cerebellum, and brainstem were significantly reduced (all P < 0.05) in early stages of pregnancy (GA <26 weeks), with differences becoming progressively greater with increasing GA. Compared with normal fetuses, e-CSF, e-CSF to ICV ratio, and VV were higher in fetuses with CHD (all P < 0.05). However, ICV volume and the GMV to SBV ratio were not significantly reduced in the CHD group (P = 0.94 and P = 0.13, respectively) during the middle gestation (GA <26 weeks). DATA CONCLUSION: There appear to be alterations of brain development trajectory in CHD fetuses that can be detected by 3D volumetric MRI in the earlier stages of pregnancy. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 3.


Assuntos
Cardiopatias Congênitas , Diagnóstico Pré-Natal , Encéfalo/diagnóstico por imagem , Feminino , Feto , Cardiopatias Congênitas/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Lactente , Imageamento por Ressonância Magnética , Gravidez , Estudos Retrospectivos
2.
Front Pediatr ; 12: 1354475, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567183

RESUMO

Objective: There are differences in the vulnerability of male and female fetal brains to adverse intrauterine exposure, preterm birth, and associated perinatal brain injury. The main objective of this study was to identify any statistically significant difference in the change of apparent diffusion coefficient (ADC) in the intracranial regions of male and female fetuses in the second and third trimesters. Methods: Diffusion-weighted imaging (DWI) was performed in 200 fetuses between 20 and 37 gestational ages (GA) with normal results or suspicious results on sonography followed by structural MRI. Pairwise ADC values of the regions of interest (ROIs) were manually delineated on either side of the cerebral white matter: frontal white matter (FWM), parietal white matter (PWM), occipital white matter (OWM), temporal white matter (TWM), basal ganglia (BG), thalamus (THA), cerebellar hemisphere (CBM), and a single measurement in the pons. The changes in these values were studied over the gestational range, along with potential sex differences and asymmetries of the cerebral hemispheres. Results: During the third trimester, ADC values in OWM, TWM, and CBM were significantly higher in male fetuses than those in female fetuses (p < 0.05). After the correction of false-discovery rates (FDR), the difference in CBM was the only statistically significant (p = 0.0032). However, the decreased rate of ADC values in male fetuses in CWM (except for FWM), BG, THA, CBM, and pons was higher than that in female fetuses during the second and third trimesters. Conclusions: We have shown some differences in the intracranial regional ADC changes between male and female fetuses using in utero DWI during the second and third trimesters.

3.
Behav Sci (Basel) ; 13(2)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36829341

RESUMO

A World Heritage Site is a masterpiece of mankind and/or nature that possesses outstanding universal value (OUV). In this regard, the 5Cs strategic objectives (credibility, communication, capacity-building, conservation, and community) set by the World Heritage Committee have become a main issue for WHS sustainable development. As one of the key stakeholders of WHS, tourist's perceived OUV attractiveness, congestion, and attitudinal behavior have significant implications for heritage protection and tourism's sustainable development. Based on the perspectives of OUV attractiveness and perceived tourist crowding, and taking into account destination attachment, the influencing factors and mechanisms of tourist satisfaction are investigated. In view of the 536 questionnaire responses from tourists of Mount Sanqingshan National Park, the structural equation modeling approach was employed to study tourist satisfaction. The conclusions were sketched: (1) tourist crowding perception did not have a significant negative effect on OUV attractiveness; destination attachment, and tourist satisfaction, and the degree of crowding perception was low; (2) the OUV attractiveness has a significant positive influence on destination attachment and tourist satisfaction, which fully highlights the charm of OUV and its important role in shaping tourists' attitudes/behaviors; (3) destination attachment has a significant positive effect on tourist satisfaction, indicating that tourists' heritage-place attachment contributes to tourist satisfaction. Finally, the analysis of tourism crowding, OUV, and the satisfaction framework proposed broaden the horizons of visitor satisfaction research, which is also a positive response to the strategic objectives of the 5Cs of WHS, with some practical implications for heritage preservation and visitor management in World Heritage Sites.

4.
Environ Sci Pollut Res Int ; 30(17): 48868-48902, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36884171

RESUMO

Concerns over the ecotoxicological effects of active pharmaceutical ingredients (APIs) on aquatic invertebrates have been raised in the last decade. While numerous studies have reported the toxicity of APIs in invertebrates, no attempt has been made to synthesize and interpret this dataset in terms of different exposure scenarios (acute, chronic, multigenerational), multiple crustacean species, and the toxic mechanisms. In this study, a thorough literature review was performed to summarize the ecotoxicological data of APIs tested on a range of invertebrates. Therapeutic classes including antidepressants, anti-infectives, antineoplastic agents, hormonal contraceptives, immunosuppressants, and neuro-active drugs exhibited higher toxicity to crustaceans than other API groups. The species sensitivity towards APIs exposure is compared in D. magna and other crustacean species. In the case of acute and chronic bioassays, ecotoxicological studies mainly focus on the apical endpoints including growth and reproduction, whereas sex ratio and molting frequency are commonly used for evaluating the substances with endocrine-disrupting properties. The multigenerational and "Omics" studies, primarily transcriptomics and metabolomics, were confined to a few API groups including beta-blocking agents, blood lipid-lowing agents, neuroactive agents, anticancer drugs, and synthetic hormones. We emphasize that in-depth studies on the multigenerational effects and the toxic mechanisms of APIs on the endocrine systems of freshwater crustacean are warranted.


Assuntos
Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/análise , Invertebrados , Reprodução , Crustáceos , Água Doce , Preparações Farmacêuticas , Daphnia
5.
Environ Toxicol Pharmacol ; 95: 103964, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36028164

RESUMO

Cytotoxic drugs have been recognized by the European Union as the potential threat in the aquatic environment. As a typical cytotoxic drug, effects of long-term exposure to cisplatin at the environmentally relevant concentrations on the crustacean health and its molecular mechanism remain undetermined. In this study, the growth and reproduction of Daphnia magna resulting from cisplatin exposure were initially assessed. While the phenotypes were not altered in 2 µg L-1, 20 µg L-1, and 200 µg L-1 treatment groups, cisplatin at 500 µg L-1 significantly reduced the offspring number to 8-13 neonates in each brood, which was lower than 13-27 neonates in the control group. In addition to the delay in the time of first pregnancy, the body length was decreased by approximate 12.13% at day 7. Meanwhile, all daphnids died after exposure to 500 µg L-1 cisplatin for 17 days. Transcriptome profiling bioassays were performed for 10 days to explore the alternation at the molecular level. Briefly, 980 (257 up- and 723 down-regulated), 429 (182 up- and 247 down-regulated) and 1984 (616 up-regulated and 1368 down-regulated) genes were differentially expressed (adj p < 0.05) in low (2 µg L-1), medium (200 µg L-1) and high (500 µg L-1) cisplatin treatment groups, respectively. Differentially expressed genes were primarily enriched in the digestion and absorption, nerve conduction, endocrine interference, and circulatory related pathways. Specifically, the down-regulated digestive secretion and nutrient absorption and neuronal conduction pathways may lead to insufficient energy supply involved in growth and reproduction, and hinder ovarian development and cell growth. Down-regulation of ovarian steroids and relaxin signaling pathways may be related to the reduction of offspring number and delayed pregnancy, and reduced body length of D. magna may attribute to the enrichment of insulin secretion pathway. In addition, the death of D. magna may result from the reduced expression of genes in cardiomyocyte contraction and apoptosome processes. Taken together, this study revealed the potential toxic mechanism of cisplatin in a model water flea.


Assuntos
Antineoplásicos , Cladocera , Insulinas , Relaxina , Poluentes Químicos da Água , Animais , Antineoplásicos/toxicidade , Apoptossomas , Cisplatino/toxicidade , Daphnia/genética , Insulinas/farmacologia , Relaxina/farmacologia , Reprodução , Transcriptoma , Poluentes Químicos da Água/toxicidade
6.
Front Neurosci ; 16: 886083, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35645723

RESUMO

Objective: The purpose of this study is to establish a reference of intracranial structure volumes in normal fetuses ranging from 19 to 37 weeks' gestation (mean 27 weeks). Materials and Methods: A retrospective analysis of 188 MRI examinations (1.5 T) of fetuses with a normal brain appearance (19-37 gestational weeks) from January 2018 to December 2021 was included in this study. Three dimensional (3-D) volumetric parameters from slice-to-volume reconstructed (SVR) images, such as total brain volume (TBV), cortical gray matter volume (GMV), subcortical brain tissue volume (SBV), intracranial cavity volume (ICV), lateral ventricles volume (VV), cerebellum volume (CBV), brainstem volume (BM), and extra-cerebrospinal fluid volume (e-CSFV), were quantified by manual segmentation from two experts. The mean, SD, minimum, maximum, median, and 25th and 75th quartiles for intracranial structures volume were calculated per gestational week. A linear regression analysis was used to determine the gestational weekly age-related change adjusted for sex. A t-test was used to compare the mean TBV and ICV values to previously reported values at each gestational week. The formulas to calculate intracranial structures volume derived from our data were created using a regression model. In addition, we compared the predicted mean TBV values derived by our formula with the expected mean TBV predicted by the previously reported Jarvis' formula at each time point. For intracranial volumes, the intraclass correlation coefficient (ICC) was calculated to convey association within and between observers. Results: The intracranial volume data are shown in graphs and tabular summaries. The male fetuses had significantly larger VV compared with female fetuses (p = 0.01). Measured mean ICV values at 19 weeks are significantly different from those published in the literature (p < 0.05). Means were compared with the expected TBV generated by the previously reported formula, showing statistically differences at 22, 26, 29, and 30 weeks' gestational age (GA) (all p < 0.05). A comparison between our data-derived formula and the previously reported formula for TBV showed very similar values at every GA. The predicted TBV means derived from the previously reported formula were all within the 95% confidence interval (CI) of the predicted means of this study. Intra- and inter-observer agreement was high, with an intraclass correlation coefficient larger than 0.98. Conclusion: We have shown that the intracranial structural volume of the fetal brain can be reliably quantified using 3-D volumetric MRI with a high degree of reproducibility and reinforces the existing data with more robust data in the earlier second and third stages of pregnancy.

7.
Sci Rep ; 10(1): 12373, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32704065

RESUMO

Unlike ultrasound (US) imaging, foetal magnetic resonance imaging (MRI) is not significantly limited by maternal obesity, oligohydramnios, uterine myoma, twins, and foetal lie, which impair US visualization of the foetus. The present study aimed to introduce our foetal cardiac MRI scanning technology and over 14-years of experience on the potential utility of foetal cardiac MRI examination as an adjunct to foetal technically inadequate echocardiography (Echo). This retrospective review included 1,573 pregnant women [1,619 foetuses (46 twins)] referred for a foetal cardiac MRI because of technically limited Echo. Foetal cardiac MRI was performed using two 1.5 T units. Among the 1,619 foetuses referred for cardiac MRI, 1,379 (85.2%) cases were followed up using postnatal imaging and/or surgery, 240 (14.8%), including three twins, had no follow-up confirmation because of pregnancy termination without autopsy or loss to follow-up. The results of the present study indicated that foetal cardiac MRI examinations can be a useful adjunct to foetal echocardiography when the technical limitations of echocardiography make it inadequate for diagnosis.


Assuntos
Ecocardiografia , Coração Fetal/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Diagnóstico Pré-Natal , Ultrassonografia Pré-Natal , Adulto , Feminino , Seguimentos , Humanos , Gravidez , Gravidez de Gêmeos , Estudos Retrospectivos , Gêmeos
8.
Bioresour Technol ; 291: 121856, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31357040

RESUMO

In this work, cornstalk (CS) was irradiated by high energy electron beam to obtain honeycomb-like porous CS (PCS). The PCS was loaded with ammonium sulfite (AS) and then coated by polyvinyl alcohol (PVA)-Fe3O4 to obtain PCS-AS@PVA-Fe3O4. The PCS-AS@PVA-Fe3O4 could reduce hexavalent chromium (Cr(VI)) to trivalent chromium (Cr(III)) by SO32-, then the Cr(III) combined with PCS-AS@PVA-Fe3O4 through hydrogen bonds. The resulting PCS-AS@PVA-Fe3O4/Cr with a high magnetism could be conveniently separated from water via a magnet. PCS-AS@PVA-Fe3O4/Cr showed a high performance on controlling Cr(VI) migration in soil and uptake by plant. Meanwhile, ammonium could be released from PCS-AS@PVA-Fe3O4, favoring plant growth. Therefore, this work not only provides a promising and low-cost approach to remove Cr(VI) and promote plant growth simultaneously, but also provides a new route for CS recycling, which might have a potential application value.


Assuntos
Compostos de Amônio/química , Cromo/isolamento & purificação , Magnetismo , Álcool de Polivinil/química , Água
9.
Sci Total Environ ; 688: 1124-1136, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31726543

RESUMO

Diesel fuel (DF)-contamination remediation has aroused increasing concern in environmental field. In our work, nano sponge was modified by silylation of amino silicon oil (ASO) and aminopropyltriethoxysilane (APTES) to obtain hydrophobic nano sponge (SPAA). SPAA possessed a micro/nano network structure and could efficiently adsorb DF through hydrophobic polysiloxane group. The results revealed that SPAA could effectively remove DF and control its migration in water and soil under various conditions. Importantly, SPAA could inhibit the harmful effect of DF on the growth of plants, earthworms, and fish. Therefore, this work provides a promising and low-cost approach for removal of DF from water and soil, which might have a potential application value.

10.
J Food Sci ; 83(4): 1173-1178, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29524212

RESUMO

Because of the wide use of chromium-containing feed, much hexavalent chromium (Cr(VI)) tends to accumulate in pork. In order to decrease the toxicity of Cr(VI)-containing pork for human beings, high-energy electron beam (HEEB) irradiation was used to reduce highly toxic Cr(VI) to low toxic trivalent chromium (Cr(III)) in lean, fat, and marbled pork. HEEB irradiation could efficiently and nondestructively reduce both free and adsorbed Cr(VI) in pork, achieving the highest reductive efficiency (RE) of 98.03%. Therein, hydrated electrons (eaq- ) and hydrogen radical (•H) generated during the irradiation process probably played key roles in the reduction. The effects of irradiation dose, initial concentration of Cr(VI), pH, temperature, salinity, and oil on the RE were investigated to obtain the optimal reduction conditions, proving the high universality of this approach. This work provides a clean and low-cost method for removing Cr(VI) from pork, which is important to ensure food safety. PRACTICAL APPLICATION: This work describes a facile, nondestructive, and clean method for removing Cr(VI) from meat product, which may have a potential application prospect in ensuring food quality and safety.


Assuntos
Cromo/química , Irradiação de Alimentos , Carne Vermelha/análise , Animais , Qualidade de Produtos para o Consumidor , Elétrons , Contaminação de Alimentos/análise , Manipulação de Alimentos , Inocuidade dos Alimentos , Concentração de Íons de Hidrogênio , Salinidade , Suínos
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