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1.
Chemistry ; 30(32): e202304003, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38573800

RESUMO

Proton exchange membrane fuel cells (PEMFCs) and alkaline membrane fuel cells (AEMFCs) have received great attention as energy devices of the next generation. Accelerating oxygen reduction reaction (ORR) kinetics is the key to improve PEMFC and AEMFC performance. Platinum-based catalysts are the most widely used catalysts for the ORR, but their high price and low abundance limit the commercialization of fuel cells. Non-noble metal-nitrogen-carbon (M-N-C) is considered to be the most likely material class to replace Pt-based catalysts, among which Fe-N-C and Co-N-C have been widely studied due to their excellent intrinsic ORR performance and have made great progress in the past decades. With the improvement of synthesis technology and a deeper understanding of the ORR mechanism, some reported Fe-N-C and Co-N-C catalysts have shown excellent ORR activity close to that of commercial Pt/C catalysts. Inspired by the progress, regulation strategies for Fe-N-C and Co-N-C catalysts are summarized in this Review from 5 perspectives: (1) coordinated atoms, (2) environmental heteroatoms and defects, (3) dual-metal active sites, (4) metal-based particle promoters, and (5) curved carbon layers. We also make suggestions on some challenges facing Fe-N-C and Co-N-C research.

2.
J Org Chem ; 88(20): 14649-14658, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37816698

RESUMO

A metal-free and selective oxidative methyl C-H functionalization of BHT with aniline compounds has been developed. This innovative method enables the facile and efficient synthesis of a diverse array of BHT-functionalized N-containing skeletons, including arylamines, benzoxazoles, benzothiazoles, benzimidazoles, quinazolines, and quinazolinones, all of which are challenging to access. The control experiment involving TEMP18O suggests that the radical adduct of TEMPO with the benzyl radical of BHT may serve as an intermediate.

3.
Mediators Inflamm ; 2023: 8215567, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035756

RESUMO

This study explored the role of T cell subsets and the expression of related microRNAs in patients with recurrent early pregnancy loss (EPL). Fifty patients with EPL loss between May 2018 and May 2021 were randomly selected as the EPL group, and 50 pregnant women with normal pregnancies or normal delivery outcomes were randomly selected as the control group. The expression levels of T cell subset-related markers and T cell subset-related miRNAs, in addition to the frequencies of T cell subsets, in peripheral blood of the two groups were analyzed. In terms of T cell-related markers, the results showed that the expression levels of the transcriptional regulator TBX-21 (T-bet) and interferon regulatory factor 4 (IRF4) were significantly upregulated in peripheral blood of the patients in the EPL group (P < 0.05), whereas the expression levels of GATA binding protein 3 (GATA3) and glucocorticoid-induced tumor necrosis factor receptor (GITR) were significantly downregulated (P < 0.05). In the EPL group, the expression of mir-106b, mir-93, and mir-25 was upregulated (1.51 ± 0.129, 1.43 ± 0.132, and 1.73 ± 0.156, respectively) in regulatory T (Treg) cell-related T cell subsets, whereas the expression of miR-146a and miR-155 was downregulated (P < 0.05). The frequencies of Treg and exhausted T cells in the EPL group were significantly lower than those in the control group (P < 0.05). The cell frequencies of T helper 17 (Th17) cells and exhausted Treg cells in the EPL group were significantly higher than those in the control group (P < 0.05). In conclusion, immune cells and associated miRNA profiles can be used as prognostic biomarkers for the treatment of human reproductive disorders, such as EPL.


Assuntos
Aborto Habitual , Perda do Embrião , MicroRNAs , Subpopulações de Linfócitos T , Feminino , Humanos , Gravidez , Aborto Habitual/genética , Aborto Habitual/imunologia , Perda do Embrião/genética , Perda do Embrião/imunologia , Expressão Gênica , MicroRNAs/genética , MicroRNAs/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia
4.
BMC Med Inform Decis Mak ; 23(1): 264, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974215

RESUMO

BACKGROUND: A large collection of dialogues between patients and doctors must be annotated for medical named entities to build intelligence for telemedicine. However, since most patients involved in telemedicine deliver related named entities in informal and long multiword expressions, it is challenging to tag their telemedicine dialogue data. This study aims to address this issue. METHODS: With the telemedicine dialogue dataset for obstetrics and gynecology taken from haodf.com, we developed guidelines and followed a two-round procedure to tag six types of named entities, including disease, symptom, time, pharmaceutical, operation, and examination. Additionally, we developed four deep-learning models based on this dataset to establish a benchmark for named-entity recognition (NER). RESULTS: The distilled obstetrics and gynecology dataset contains 2,383 consultations between doctors and patients, of which 13,411 sentences were from doctors, and 17,929 were from patients. With 63,560 named entities in total, the average number of characters per named entity is 4.33. The experimental results suggest that LatticeLSTM performs best on our dataset in terms of accuracy, precision, recall, and F score. CONCLUSION: Compared with other datasets, this dataset offers three novel facets. This study offers intricately tagged long multiword expressions for medical named entities. Second, this study is one of the first attempts to mark temporal entities in a medical dataset. Third, this annotated dataset is balanced across the six types of labels, which we believe will play a considerable role in expanding telemedicine artificial intelligence.


Assuntos
Inteligência Artificial , População do Leste Asiático , Telemedicina , Humanos , Idioma , Curadoria de Dados
5.
J Obstet Gynaecol Res ; 49(9): 2273-2282, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37354102

RESUMO

AIM: This study aimed to characterize the pathological types, diagnosis, chromosomal abnormalities, and postnatal clinical manifestations of right and double aortic arch malformations in fetuses. METHODS: In this retrospective study, all fetuses diagnosed with right or double aortic arch anomalies for whom conventional two-dimensional echocardiography combined with spatio-temporal image correlation was performed at our tertiary referral center between December 2012 and December 2021 were included. RESULTS: In total, 234 fetuses with aortic arch abnormalities were identified. Forty-one cases lost to follow-up. One hundred ninety-three cases were included in this study. One hundred eighty-seven cases with right aortic arch. Six cases with double aortic arch. Most cases of right aortic arch with aberrant left subclavian artery (77/101, 76.2%) were isolated lesions, whereas most of those with mirror-image branching (45/75, 60%) were associated with intracardiac or extracardiac anomalies. Chromosomal abnormalities were screened prenatally in 113 fetuses with right aortic arch, among whom three with aberrant left subclavian artery (3/63, 4.8%) and eight with mirror-image branching (8/50, 16%) had chromosome anomalies (p < 0.05). Furthermore, three cases had microdeletion 22q11.2 and these were significantly associated with intracardiac malformations. CONCLUSIONS: Most cases of isolated right aortic arch do not present with clinical symptoms except isolated left subclavian artery and isolated left brachiocephalic trunk. In addition, the risk of chromosomal abnormalities in patients with isolated right aortic arch is very low. We recommend that pregnant women should be informed of the risks and benefits of undergoing invasive prenatal chromosomal detection.


Assuntos
Cardiopatias Congênitas , Anel Vascular , Humanos , Feminino , Gravidez , Anel Vascular/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/anormalidades , Estudos Retrospectivos , Ultrassonografia Pré-Natal/métodos , Diagnóstico Pré-Natal , Cardiopatias Congênitas/diagnóstico por imagem , Feto , Aberrações Cromossômicas , Prognóstico
6.
Environ Toxicol ; 38(1): 28-38, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36114797

RESUMO

Dysregulated follicular development may lead to follicular atresia, and this is associated with oxidative stress in granulosa cells. Kurarinone is a natural compound possessing multiple activities, including antioxidative ability. However, the role of kurarinone in granulosa cell damage during follicular atresia remains unknown. Human ovarian granulosa KGN cells were treated with hydrogen peroxide (H2 O2 ) to induce cellular damage. Cytotoxicity was investigated by lactate dehydrogenase (LDH) release assay. Oxidative stress was evaluated by detection of reactive oxygen species (ROS) generation and oxidative biomarker levels. Cell apoptosis was evaluated by flow cytometry, a Cell Death Detection ELISA Kit, and a Caspase-3 Assay Kit. The downstream target and related signaling pathway were analyzed by western blotting. Kurarinone attenuated H2 O2 -induced LDH release in KGN cells. Kurarinone relieved H2 O2 -induced increase in ROS generation and malondialdehyde level as well as decrease in superoxide dismutase-1 activity and heme oxygenase 1 and NAD(P)H quinone dehydrogenase 1 mRNA levels. Kurarinone inhibited H2 O2 -induced apoptosis in KGN cells. Kurarinone targeted insulin-like growth factor 1 (IGF1) and upregulated IGF1 expression to activate the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling. IGF1 silencing attenuated the suppressive effects of kurarinone on H2 O2 -induced oxidative stress and apoptosis in KGN cells. In conclusion, kurarinone attenuates H2 O2 -induced oxidative stress and apoptosis in KGN cells through activating the PI3K/Akt signaling by upregulating IGF1 expression, indicating the therapeutic potential of kurarinone in follicular atresia.


Assuntos
Peróxido de Hidrogênio , Proteínas Proto-Oncogênicas c-akt , Humanos , Feminino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Peróxido de Hidrogênio/toxicidade , Peróxido de Hidrogênio/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Atresia Folicular , Estresse Oxidativo , Transdução de Sinais , Apoptose , Células da Granulosa/metabolismo
7.
Korean J Physiol Pharmacol ; 27(3): 209-220, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078295

RESUMO

This study is to determine the regulation of nitric oxide synthase 3 (NOS3) by edaravone in mice with hypoxic pulmonary hypertension (HPH). C57BL/6J mice were reared in a hypoxic chamber. HPH mice were treated with edaravone or edaravone + L-NMMA (a NOS inhibitor). Lung tissue was collected for histological assessment, apoptosis analysis, and detection of malondialdehyde, superoxide dismutase, tumor necrosis factor (TNF)-α, interleukin (IL)-6, and NOS3. The levels of serum TNF-α and IL-6 were also measured. Immunohistochemistry was used to visualize the expression of α-smooth muscle actin (SMA) in pulmonary arterioles. Edaravone treatment improved hemodynamics, inhibited right ventricular hypertrophy, increased NOS3 expression, and reduced pathological changes, pulmonary artery wall thickness, apoptotic pulmonary cells, oxidative stress, and the expression of TNF-α, IL-6, and α-SMA in HPH mice. L-NMMA treatment counteracted the lung protective effects of edaravone. In conclusion, edaravone might reduce lung damage in HPH mice by increasing the expression of NOS3.

8.
Angew Chem Int Ed Engl ; 62(34): e202306166, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37309017

RESUMO

To achieve the Fe-N-C materials with both high activity and durability in proton exchange membrane fuel cells, the attack of free radicals on Fe-N4 sites must be overcome. Herein, we report a strategy to effectively eliminate radicals at the source to mitigate the degradation by anchoring CeO2 nanoparticles as radicals scavengers adjacent (Scaad-CeO2 ) to the Fe-N4 sites. Radicals such as ⋅OH and HO2 ⋅ that form at Fe-N4 sites can be instantaneously eliminated by adjacent CeO2 , which shortens the survival time of radicals and the regional space of their damage. As a result, the CeO2 scavengers in Fe-NC/Scaad-CeO2 achieved ∼80 % elimination of the radicals generated at the Fe-N4 sites. A fuel cell prepared with the Fe-NC/Scaad-CeO2 showed a smaller peak power density decay after 30,000 cycles determined with US DOE PGM-relevant AST, increasing the decay of Fe-NCPhen from 69 % to 28 % decay.

9.
Arch Biochem Biophys ; 712: 109026, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34506757

RESUMO

Structural maintenance of chromosomes 4 (SMC4) has an important role in chromosome condensation and segregation, which is involved in regulating multiple tumor development. However, the role of SMC4 in endometrial cancer is uncertain. The expression and prognostic value of SMC4 were predicted by UALCAN, Gene Expression Omnibus (GEO), The Human Protein Atlas and Kaplan Meier plotter tools. SMC4-related genes were analyzed by LinkedOmics, Gene Ontology (GO) annotations, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Forkhead box protein O1 (FoxO1) activity was suppressed by AS1842856 (AS). SMC4, Ki67, B-cell lymphoma-2(Bcl-2), Bcl-2 associated X protein (Bax), FoxO1, phosphorylated FoxO1 (p-FoxO1), and p27 protein levels were detected by Western blotting. Cell proliferation was detected using Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) analyses. Cell apoptosis was measured using TUNEL analysis. SMC4 abundance was increased in endometrial cancer, and predicted a worse overall survival. SMC4 knockdown repressed proliferative ability of endometrial cancer cells and promoted cell apoptosis. SMC4 knockdown promoted FoxO1 transactivation by decreasing its phosphorylated level. Addition of AS inhibited FoxO1 activity by increasing the phosphorylated level of FoxO1. The inhibition of FoxO1 activity reversed the effect of SMC4 silencing on cell proliferation and apoptosis. In conclusion, SMC4 silencing restrained cell proliferation and facilitated apoptosis in endometrial cancer via regulating FoxO1 activity.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Neoplasias do Endométrio/metabolismo , Proteína Forkhead Box O1/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Adenosina Trifosfatases/genética , Apoptose/fisiologia , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Proteínas Cromossômicas não Histona/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Ativação Transcricional/fisiologia
10.
Environ Toxicol ; 36(12): 2512-2520, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34480403

RESUMO

Endometrial cancer (EC) ranks as the most prevalent malignancy occurring in the female genital tract. Non-SMC condensin I complex subunit G (NCAPG), a mitotic associated chromosomal condensing protein, is reported to be frequently abnormally expressed in several tumors and plays a vital role in carcinogenesis. Our study aimed to explore the effect of NCAPG on cell proliferation and apoptosis in EC cells and to determine the underlying mechanism. Expression and survival data of NCAPG in EC tissues were analyzed by bioinformatics methods. Cell proliferation was evaluated by EdU and CCK-8 assays. Apoptosis was assessed by flow cytometry analysis. Expression of NCAPG, proliferating cell nuclear antigen (PCNA), Ki67, Bcl-2, Bax, active caspase-3, active ß-catenin, and c-Myc were determined by western blotting. NCAPG was highly expressed in EC tissues and cells and predicted poor survival for EC patients. NCAPG knockdown inhibited cell proliferation and induced apoptosis in EC cells. Additionally, NCAPG knockdown inactivated the Wnt/ß-catenin pathway in EC cells. Mechanistically, ß-catenin overexpression blocked the tumorigenic effects of NCAPG in EC cells. In conclusion, NCAPG silencing inhibited cell proliferation and induced apoptosis in EC cells via inhibiting the Wnt/ß-catenin pathway.


Assuntos
Neoplasias do Endométrio , beta Catenina , Apoptose , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Endométrio/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
11.
Prenat Diagn ; 40(7): 892-904, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32279335

RESUMO

OBJECTIVES: Establish a fetal heart anatomical cross-sectional database that correlates with screening transverse ultrasound images suggested by international professional organizations to detect congenital heart defects. METHODS: Fetuses with suspected congenital heart defects identified using the following cardiac image sequences obtained from transverse slices beginning from the upper abdomen and ending in the upper thorax were the subjects of this study: (1) four-chamber view, (2) left ventricular outflow tract view, (3) three-vessel right ventricular outflow tract view, and (4) the three-vessel tracheal view. A database of digital two-dimensional images of the transverse sweep was created for fetuses with confirmed congenital heart defects. In addition, using four-dimensional ultrasound spatial-temporal image correlation, selected transverse ultrasound images were acquired as part of the database. Ultrasound-detected congenital heart defects were confirmed postnatally from pathological specimens of the heart and lungs using a cross-sectional technique that mirrored the ultrasound images described above. When anatomical specimens were not available, prenatal ultrasound-detected congenital heart defects were confirmed using postnatal echocardiography and/or following surgery. RESULTS: The four screening views described in the Methods section identified 160 fetuses that comprised the database. Forty-five datasets consisted of both ultrasound and anatomical cross-sectional images. Thirteen percent (6/45) only had abnormalities of the four-chamber view (eg, endocardial cushion defects). Twenty-four percent (11/45) had abnormalities of the four-chamber view as well as right and left outflow tracts (eg, complex malformations). Of these, 10 of 11 had an abnormal tracheal view. Sixteen percent (7/45) had an abnormal four-chamber view and abnormal right outflow tract (eg, pulmonary stenosis). Thirty-three percent (15/45) had a normal four-chamber view but had abnormal right and left outflow tracts as well as an abnormal tracheal view (eg, tetralogy of Fallot, D-transposition of the great arteries). CONCLUSIONS: Combining both ultrasound and anatomical imaging may be of assistance in training imagers to recognize cardiovascular pathology when performing the screening examination of the fetal heart.


Assuntos
Anatomia Transversal , Bases de Dados Factuais/provisão & distribuição , Coração Fetal/anatomia & histologia , Cardiopatias Congênitas/patologia , Adulto , Bases de Dados Factuais/estatística & dados numéricos , Conjuntos de Dados como Assunto , Feminino , Coração Fetal/anormalidades , Coração Fetal/diagnóstico por imagem , Coração Fetal/patologia , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/epidemiologia , Humanos , Recém-Nascido , Masculino , Prontuários Médicos/estatística & dados numéricos , Gravidez , Ultrassonografia Pré-Natal/métodos , Ultrassonografia Pré-Natal/estatística & dados numéricos , Adulto Jovem
12.
J Obstet Gynaecol Res ; 46(10): 1988-1993, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32761766

RESUMO

AIM: To review our experience with the prenatal diagnosis of congenital portosystemic shunt (CPSS). METHODS: This is a retrospective study of CPSS cases examined at an ultrasonographic tertiary referral center from 2013 to 2019. The anatomical origin and drainage of the shunt were assessed. Feto-maternal clinical characteristics and long-term outcomes were investigated via medical files and telephone interviews with the mothers. RESULTS: Eleven cases were reviewed. Based on the anatomical origins, before or after portal vein division, cases were classified into extrahepatic portosystemic shunt (EHPSS, n = 3, 27.3%) and intrahepatic portosystemic shunt (IHPSS, n = 8, 72.7%). Additional abnormalities were also observed in the EHPSS (n = 2, 66.7%) and IHPSS (n = 3, 37.5%) groups. Intrauterine growth restriction was the most common abnormality (n = 4, 80%). The median age of the pregnant women was 31.9 years (range 26 ~ 43 years). Most cases (n = 8, 72.7%) were diagnosed in the third trimester, and the median gestational age was 31+5 weeks (range 24 ~ 36+6 weeks). Three cases underwent karyotype examinations, and one had trisomy 13. The median time after birth was 2 years (range 0.7 ~ 5.7 years). The overall postnatal live-birth rate was 60% (6/10), not including one case with no data on pregnancy outcome. The mothers of the six live births indicated that their children were in excellent health. CONCLUSION: This study indicates that prenatal CPSS diagnosis is feasible, especially in the third trimester. IHPSS is more common than EHPSS. Complicated cases most often occur with EHPSS. Intrauterine growth restriction is the most common concomitant abnormality. The prognosis of most cases is good.


Assuntos
Derivação Portossistêmica Transjugular Intra-Hepática , Malformações Vasculares , Adulto , Feminino , Humanos , Veia Porta/diagnóstico por imagem , Gravidez , Diagnóstico Pré-Natal , Estudos Retrospectivos
13.
Pediatr Cardiol ; 39(8): 1656, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30315338

RESUMO

The article Prenatal Ultrasonic Diagnosis and Prognostic Analysis of Isolated Left Subclavian Artery (ILSCA) and Left Brachiocephalic Trunk (ILBCT)Malformation, written by Yuntao Li, Xiaohong Zhang, Yani Yan and Qiuyan Pei, was originally published electronically on the publisher's internet portal (currently SpringerLink) on August 2018 with open access.

14.
Pediatr Cardiol ; 39(8): 1650-1655, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30167747

RESUMO

The purpose of the study was to explore the prognosis, as well as antenatal ultrasonic features of isolated left subclavian artery (ILSCA) and isolated left brachiocephalic trunk (ILBCT) malformations, in order to improve prognosis and provide guidance for prenatal diagnosis. The origin and routing of cephalic and cervical vessels were observed in patients diagnosed with right aortic arch or right arterial duct arch in our hospital from March 2015 to March 2017, and the spectrum features related to ILSCA and ILBCT were analyzed. Fetuses diagnosed as ILSCA, or, and ILBCT were followed up for 3 months after birth. At the same time, a literature review was carried out for ILBCT and ILSCA in Pubmed. In our study, two cases with ILSCA and ILBCT were both diagnosed prenatally. They are not accompanied by other congenital malformations or chromosome abnormalities. No abnormality was found during postnatal follow-up except that left radial pulsation was weakened and blood pressure of the left upper limb decreased in baby with ILSCA. In baby with ILBCT, in addition to these abnormal changes, the left common carotid artery pulse disappearance too. In pubmed, three of 12 ILSCA or ILBCT did not have other congenital malformation or chromosome abnormalities. They were not diagnosed until the age of 3, 10, and 47 because of school exams or atypical symptoms, such as headaches, chest pain. Symptom of ILBCT or ILSCA without other abnormality is silent, and therefore they cannot be diagnosed timely after birth prenatal diagnosis is necessary for they can be treated in time.


Assuntos
Síndromes do Arco Aórtico/diagnóstico por imagem , Tronco Braquiocefálico/anormalidades , Artéria Subclávia/anormalidades , Ultrassonografia Pré-Natal/métodos , Aorta Torácica/diagnóstico por imagem , Tronco Braquiocefálico/diagnóstico por imagem , Feminino , Humanos , Masculino , Gravidez , Prognóstico , Artéria Subclávia/diagnóstico por imagem
15.
Water Res ; 258: 121767, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38754296

RESUMO

The co-occurrence of high As and F concentrations in saline groundwater in arid and semi-arid regions has attracted considerable attention. However, the factors determining the elevated concentrations of the two elements in surface water in these regions have not been sufficiently studied, and their implications for the poor-quality of local groundwater (high levels of As, F, and salinity) are unknown. A total of 18 water samples were collected from Wuliangsu Lake, irrigation/drainage channels, and the Huanghe (i.e., Yellow River) in the Hetao Basin, China. The pH, concentrations of As and F as well as those of other major elements, and stable isotope (H and O) compositions were analyzed. The water samples had a high pH (7.85-9.01, mean 8.25) and high TDS (402-9778 mg/L, mean 1920 mg/L) values. In six of the 10 lake samples, As concentration was above 10 µg/L (maximum 69.1 µg/L) and, in one of them, F concentration was above 1.5 mg/L. Interestingly, the high As, F, and TDS values simultaneously detected in the lake water were similar to those previously reported in local groundwater, and all water samples showed a significant positive correlation between As and F concentrations (R2 = 0.96, p < 0.01), except for two samples with abnormally high Ca2+ levels. The results of stable isotope analysis and Cl/Br ratios suggested that the lake experienced strong evaporation, which is consistent with the high TDS values. Evaporative concentration is suggested as the main factor contributing to the elevated As and F concentrations in the lake water. In addition, the major ions (e.g., Na+, Cl-, HCO3-, and OH-) and pH in the lake water increased during evaporation, leading to desorption of As and F. Thus, the evaporation process, including evaporative concentration and desorption, was considered primarily responsible for the elevated As and F in the lake water. Based on the results of this study, we presume that the paleolakes in the study area have experienced intense evaporation process. As a result, As, F, and major elements accumulated in sediments (or residual lake water) and were buried in the fluvial basins; then, they were released into the groundwater through multiple (bio)hydrogeochemical processes. By combining the results of this study with those obtained from previous groundwater analyses, we propose a new hypothesis explaining the origin of elevated As and F concentrations in saline groundwater in arid and semi-arid regions.


Assuntos
Arsênio , Fluoretos , Água Subterrânea , Lagos , Poluentes Químicos da Água , Água Subterrânea/química , Lagos/química , China , Arsênio/análise , Poluentes Químicos da Água/análise , Fluoretos/análise , Monitoramento Ambiental , Rios/química , Concentração de Íons de Hidrogênio
16.
ACS Nano ; 18(1): 551-559, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38112383

RESUMO

The exorbitant cost of Pt-based electrocatalysts and the poor durability of non-noble metal electrocatalysts for proton exchange membrane fuel cells limited their practical application. Here, FeN4 active sites electronically coupled with PtFe alloys (PtFe-FeNC) were successfully prepared by a vapor deposition strategy as an ultralow Pt loading (0.64 wt %) hybrid electrocatalyst. The FeN4 sites on the FeNC matrix are able to effectively anchor the PtFe alloys, thus inhibiting their aggregation during long-life cycling. These PtFe alloys, in turn, can efficiently restrain the leaching of the FeN4 sites from the FeNC matrix. Thus, the PtFe-FeNC demonstrated an improved Pt mass activity of 2.33 A mgPt-1 at 0.9 V toward oxygen reduction reaction, which is 12.9 times higher than that of commercial Pt/C (0.18 A mgPt-1). It demonstrated great stability, with the Pt mass activity decreasing by only 9.4% after 70,000 cycles. Importantly, the fuel cell with an ultralow Pt loading in the cathode (0.012 mgPt cm-2) displays a high Pt mass activity of 1.75 A mgPt-1 at 0.9 ViR-free, which is significantly better than commercial MEA (0.25 A mgPt-1). Interestingly, PtFe-FeNC catalysts possess enhanced durability, exhibiting a 12.5% decrease in peak power density compared to the 51.7% decrease of FeNC.

17.
Zhonghua Yi Xue Za Zhi ; 93(37): 2986-8, 2013 Oct 08.
Artigo em Zh | MEDLINE | ID: mdl-24401591

RESUMO

OBJECTIVE: To evaluate the application value of laparoscopic ultrasonography (LUS) in gynecological surgery. METHODS: Retrospective analyses were performed for 52 cases undergoing LUS during laparoscopic extirpation/excision of gynecological tumors. Aloka 7.5-MHz laparoscopic probe was used to detect the residual lesions during laparoscopic operations. The findings of LUS were compared with those of preoperative transvaginal ultrasound and postoperative pathohistological examinations. RESULTS: Preoperative diagnoses were corrected by LUS in 9 cases. And 34 residual lesions located by LUS were successfully removed. CONCLUSION: With a high detection rate and diagnostic accuracy rate in the diagnosis of gynecologic disease, LUS can locate invisible lesions during laparoscopic operations and provide guidance for radical tumor removal. It is a safe and valuable assistance for gynecologic surgery.


Assuntos
Endossonografia , Procedimentos Cirúrgicos em Ginecologia/métodos , Laparoscopia , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
18.
Sci Total Environ ; 898: 165547, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37454847

RESUMO

Wetting-drying cycles in the environment could change the inner- or outer-sphere complexation of heavy metal cations on natural organic matter (NOM) and then influence ternary interactions with organic contaminants - a rarely-discussed essential geochemical process. In this work, the sorption of sulfamethoxazole (SMX) on humic acids (HAs) mediated by cations (Cu2+ and Cd2+) was investigated. Considering that outer-sphere complexation could be transformed into inner-sphere complexation during vacuum freeze-drying, the role of inner- or outer-sphere complexation on SMX sorption was explored. The experimental sorption results and density functional theory (DFT) calculations suggested that Cu2+ and Cd2+ sorption on HAs was mainly outer- and inner-sphere complexation, respectively. Cd2+ consistently promoted SMX sorption on HAs, while Cu2+ promoted and inhibited SMX sorption before and after freeze-drying. The structure of HA-Cu complexes with inner-sphere complexation was more compact than those with outer-sphere complexation, which reduced the accessibility of sorption sites for SMX on HA-Cu and inhibited SMX sorption. However, the greater number of coordination sites of Cd2+ may provide more sorption sites and the structure of HA-Cd was looser. These findings provide a groundbreaking understanding of the sorption of organics on natural adsorbents in the presence of cations.

19.
Front Immunol ; 14: 1145146, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006292

RESUMO

Background: Bleeding complications are recognized as relatively infrequent manifestations of antiphospholipid syndrome (APS), and the safety of antithrombotic therapy during pregnancy is of concern. This study aims to assess the risk factors and possible associations between bleeding complications and adverse pregnancy outcomes (APOs) in patients with APS. Methods: A retrospective cohort study was conducted at the Peking University People's Hospital. The clinical and immunologic features, bleeding complications, treatment, and pregnancy outcomes of patients with APS were collected. Univariate and multivariate logistic regression analyses were applied to assess the associations between APOs and bleeding complications. Results: A total of 176 participants with obstetric APS were included in the analysis. There were 66 (37.50%) patients with APS with hemorrhage complications and 86 (48.86%) patients with APS with APOs. Mucocutaneous hemorrhage was associated with APOs including fetal death after 12 weeks [odds ratio (OR) = 10.73, 95% confidence interval (CI): 1.61-71.74, p = 0.014], preterm delivery prior to 34 weeks (OR = 8.30, 95% CI: 2.31-29.84, p = 0.001), and small for gestational age (OR = 4.17, 95% CI: 1.22-14.21, p = 0.023) in univariate logistic regression analyses. It also independently associated with preterm delivery prior to 34 weeks (OR = 40.29, 95% CI: 1.45-1121.32, p = 0.030) in multivariate logistic regression analyses. Receiver operating characteristic (ROC) analysis evaluating the accuracy of these factors for preterm delivery prior to 34 weeks showed that the area under ROC curve was 0.871. Conclusion: The study shows that mucocutaneous hemorrhage may be an indication of the occurrence of APOs in obstetric patients with APS.


Assuntos
Síndrome Antifosfolipídica , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Humanos , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/terapia , Resultado da Gravidez , Estudos Retrospectivos , Hemorragia/complicações , Fatores de Risco
20.
Diagnostics (Basel) ; 13(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37189594

RESUMO

(1) Background: The objective of this study was to investigate the diagnostic value of chromosomal microarray analysis (CMA) for congenital heart defects (CHDs) with different cardiac phenotypes and extracardiac abnormalities (ECAs) and to explore the pathogenic genetic factors of CHDs. (2) Methods: We collected fetuses diagnosed with CHDs by echocardiography at our hospital from January 2012 to December 2021. We analyzed the CMA results of 427 fetuses with CHDs. We then categorized the CHD into different groups according to two dimensions: different cardiac phenotypes and whether it was combined with ECAs. The correlation between the numerical chromosomal abnormalities (NCAs) and copy number variations (CNVs) with CHDs was analyzed. Statistical analyses, including Chi-square tests and t-tests, were performed on the data using IBM SPSS and GraphPad Prism. (3) Results: In general, CHDs with ECAs increased the detection rate for CA, especially the conotruncal defects. CHD combined with the thoracic and abdominal walls and skeletal, thymic and multiple ECAs, were more likely to exhibit CA. Among the CHD phenotypes, VSD and AVSD were associated with NCA, while DORV may be associated with NCA. The cardiac phenotypes associated with pCNVs were IAA (type A and B), RAA, TAPVC, CoA and TOF. In addition, IAA, B, RAA, PS, CoA and TOF were also associated with 22q11.2DS. The length distribution of the CNV was not significantly different between each CHD phenotype. We detected twelve CNV syndromes, of which six syndromes may be related to CHDs. The pregnancy outcome in this study suggests that termination of pregnancy with fetal VSD and vascular abnormality is more dependent on genetic diagnosis, whereas the outcome in other phenotypes of CHDs may be associated with other additional factors. (4) Conclusions: CMA examination for CHDs is still necessary. We should identify the existence of fetal ECAs and specific cardiac phenotypes, which are helpful for genetic counseling and prenatal diagnosis.

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