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1.
Front Pharmacol ; 15: 1372139, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572430

RESUMO

Background: Most preschool children are distressed during anesthesia induction. While current pharmacological methods are useful, there is a need for further optimization to an "ideal" standard. Remimazolam is an ultra-short-acting benzodiazepine, and intranasal remimazolam for pre-induction sedation may be promising. Methods: This study included 32 preschool children who underwent short and minor surgery between October 2022 and January 2023. After pretreatment with lidocaine, remimazolam was administered to both nostrils using a mucosal atomizer device. The University of Michigan Sedation Score (UMSS) was assessed for sedation 6, 9, 12, 15, and 20 min after intranasal atomization. We used Dixon's up-and-down method, and probit and isotonic regressions to determine the 50% effective dose (ED50) and 95% effective dose (ED95) of intranasal remimazolam for pre-induction sedation. Results: Twenty-nine pediatric patients were included in the final analysis. The ED50 and ED95 of intranasal remimazolam for successful pre-induction sedation, when processed via probit analysis, were 0.65 (95% confidence interval [CI], 0.59-0.71) and 0.78 mg/kg (95% CI, 0.72-1.07), respectively. In contrast, when processed by isotonic regression, they were 0.65 (95% CI: 0.58-0.72 mg/kg) and 0.78 mg/kg (95% CI: 0.69-1.08 mg/kg), respectively. At 6 min after intranasal remimazolam treatment, 81.2% (13/16) of "positive" participants were successfully sedated with a UMSS ≧ 1. All the "positive" participants were successfully sedated within 9 min. Conclusion: Intranasal remimazolam is feasible for preschool children with a short onset time. For successful pre-induction sedation, the ED50 and ED95 of intranasal remimazolam were 0.65 and 0.78 mg/kg, respectively.

2.
Water Res ; 221: 118778, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35752093

RESUMO

The electrochemical oxidation method is a promising technology for the degradation of perfluorooctane sulfonate (PFOS). However, the elimination processes of PFOS are still unknown, including the electron transfer pathway, key reactive sites, and degradation mechanism. Here, we fabricated diatomite and cerium (Ce) co-modified Sb2O3 (D-Ce/Sb2O3) anode to realize efficient degradation of PFOS via peroxymonosulfate (PMS) activation. The transferred electron and the generated hydroxyl radical (•OH) can high-effectively decompose PFOS. The electron can be rapidly transferred from the highest occupied molecular orbital of the PFOS to the lowest unoccupied molecular orbital of the PMS via the D-Ce/Sb2O3 driven by a potential energy difference under electrochemical process. The active site of Ce-O in the D-Ce/Sb2O3 can greatly reduce the migration distance of the electron and the •OH, and thus improving the catalytic activity for degrading various organic micropollutants with high stability. In addition, the electrochemical process shows strong resistance and tolerance to the changing pH, inorganic ions, and organic matter. This study offers insights into the electron transfer pathway and PMS activation mechanism in PFOS removal via electrochemical oxidation, paving the way for its potential application in water purification.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Químicos da Água , Domínio Catalítico , Fluorocarbonos , Peróxidos/química , Água , Poluentes Químicos da Água/química
3.
Water Res ; 215: 118259, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35294910

RESUMO

Polyfluoroalkyl and perfluoroalkyl chemicals (PFCs) widely used in lubricants, surfactant, textiles, paper coatings, cosmetics, and fire-fighting foams can release a large deal of organics contaminants into wastewater and pose great risks to the health of humans and eco-environments. Although advanced oxidation processes can effectively deconstruct various organic contaminants via reactive radicals, the stable structure of PFCs makes it difficult to be degraded. Here, we confirm that electrochemical oxidation process coupled with peroxymonosulfate (PMS) reaction can efficiently destroy stable structure of PFCs via electron transfer and meanwhile completely degrade PFCs via generated active radicals. We further studies via capturing and scavenging radicals, and DFT calculations find that electron hydroxyl radials play a dominant role in degrading PFCs. Based on the calculations of adsorption energy and molecular orbital energy we further demonstrate that many active sites on the surface of Ti4O7 (1 0 4) plane can rapidly take part in electrochemical reaction for generating radials and removing organic contaminants. These results give a promising insight towards high-effective and deep degradation of PFCs via electrochemical reaction coupled with advanced oxidation processes, as well as providing guidance and technical support for the remove of multiple organic contaminants.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Transporte de Elétrons , Elétrons , Humanos
4.
J Asian Nat Prod Res ; 24(9): 849-859, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34657548

RESUMO

Twelve novel cordycepin derivatives were designed and synthesized with modification at positions of 2', 5'-hydroxyl and N6 amino groups of cordycepin. The results showed that the inhibitory activities of 3, 4b, 6c and 6d on A549 were comparable to the positive control gefitinib, and the inhibitory activity of 6a on A549 was better than that of gefitinib. Also, the inhibitory activities of twelve cordycepin derivatives against E. coli 1924, S. aureus 4220 and S. mutans 3289 were studied. Among them, 4b showed certain inhibitory on S. mutans 3289, while 6b showed certain inhibition on S. aureus 4220.


Assuntos
Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Desoxiadenosinas , Gefitinibe , Estrutura Molecular , Relação Estrutura-Atividade
5.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3459-3467, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676706

RESUMO

Plantation ecosystems are more vulnerable than natural ones to global climate change. Using the dendrochronology method, we established tree-ring width chronologies of Pinus tabuliformis distributed in the semi-arid region of Northeast China. We examined its growth dynamics, analyzed the relationship between radical growth and climate factors, and explored the effects of global warming on the growth and distribution of P. tabuliformis. The results showed that tree-ring width chronologies of P. tabuliformis were negatively correlated with mean temperature of growing season (May-July), and positively correlated with precipitation and Palmer drought severity index (PDSI) in the early growing season (April) and in the growing season (May-July). Water availability was the main limiting factor for the radial growth of P. tabuliformis. Along the increasing precipitation gradient from southwest to northeast, tree growth became more sensitive to annual mean temperature, and the correlation with annual precipitation shifted from positive to negative, indicating that tree growth in the relative arid area (southwest of the study area) was more severely restricted by water availability. Drought stress caused by climate warming resulted in growth declines at some sites in the southwest area. With the continuous warming-drying climate, the distribution boundary of P. tabuliformis in the study area would shrink locally, with the suitable growth boundary moving northward.


Assuntos
Pinus , China , Mudança Climática , Ecossistema , Árvores
6.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3687-3698, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676731

RESUMO

The wood used for funeral utensil in ancient tomb is a kind of valuable materials and important for understanding vegetation, climate and society conditions in the history. Here, we identified the tree species and dated the time of wooden utensils for funeral excavated from tombs in Shuijia Village, Shenyang, using wood anatomy methods and dendrochronological techniques. The results showed that 7 out of the 16 wood samples were identified as Pinus tabuliformis from Pinaceae, 8 were Larix sp. from Pinaceae and most likely Larix olgensis, and the rest one was Acer sp. from Aceraceae. Currently, these tree species are still widely distributed in Liaoning Province, indicating that forest structure (tree species composition) is relatively stable and that the climate at that time was quite similar to that at present. The timbers used for wooden utensils of funeral for civilian tombs had regional biogeographic characteristics and reflected regional social productivity development level in Mukden (now Shenyang) in Qing Dynasty: most of them were native tree species with low cost and high availability; the main timber trees were conifer species, and a few of them were broadleaved trees. These timbers were likely from the forest in Shenyang or mountainous areas in Eastern Liaoning, with Hunhe River waterway being an important transport way for timbers to Shenyang. Some P. tabuliformis and Larix sp. timbers could be cross-dated well, and the growth period of the trees was determined to be 1680s-1770s (early to mid-Qing Dynasty). The variations of tree-ring width of these timbers had good consistency and high climate sensitivity, reflecting the consistency of regional climate and environment. These timbers have the potential to indicate the climate condition of the early to mid-Qing Dynasty.


Assuntos
Pinus , Árvores , China , Indicadores Ambientais , Florestas
7.
Huan Jing Ke Xue ; 42(8): 3985-3996, 2021 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-34309285

RESUMO

Straw returning is an effective technique for improving soil fertility and maintaining crop productivity in agro-ecosystems. The effects of straw returning, when combined with chemical fertilizer, on soil nutrients, enzyme activity, and microbial community were explored in rice-rape rotation farmland in the Chaohu Area. We carried out a 4-year field experiment (2016-2020) and set up four treatments (no straw+no fertilization, CK; conventional fertilization, F; straw returning+conventional fertilization, SF; and straw returning+conventional fertilization minus 20%, SDF) to explore the key environmental factors affecting soil enzyme activity and microbial and fungal communities. The results showed that straw returning combined with chemical fertilizer could improve soil nutrient content, with the SF treatment resulting in the highest soil nutrient content. Compared with F, the SF treatment significantly increased the organic matter (OM) and total phosphorus (TP) content of the soil, by 7.94% and 24.07%, respectively, in rice seasons (P<0.05), while the alkaline nitrogen (AN) content was significantly increased by 13.62% in rape seasons (P<0.05). Compared with F, the SF treatment also significantly increased soil phosphatase and urease, by 28.54% and 24.13% in rice seasons and 38.97% and 30.70% in rape seasons, respectively (P<0.05). Compared with F, SDF treatments significantly increased urease activity by 20.31% in rice seasons and 24.33% in rape seasons (P<0.05). The results indicated that straw returning increased both the Chao1 and Shannon indices of soil bacteria in rice seasons, whereas decreased these indices in rape seasons. However, the Chao1 and Shannon index of the fungal community increased after straw returning. In terms of microbial community structure, the relative abundance of Proteobacteria in SF and SDF treatments increased by 8.22% and 7.88% in rice seasons and 18.53% and 5.68% in rape seasons, respectively, compared with the F treatment. Compared with F, the relative abundance of Chloroflexi in SF and SDF treatments increased by 12.00% and 11.25% in rice seasons and 15.02% and 8.43% in rape seasons, respectively. Compared with F, the relative abundance of Basidiomycota in SF and SDF treatments in rice seasons increased by 70% and 43.42% (P<0.05), respectively, while ascomycetes in rape seasons increased by 69.79% and 43.72% (P<0.05), respectively. In conclusion, straw returning combined with chemical fertilizer can improve soil nutrient content. Soil urease and phosphatase were more sensitive to straw returning. The compositional changes in the bacterial community of the soil were mainly affected by soil TP and available phosphorus (AP), whereas OM, AN, and pH were the main environmental factors causing changes in the fungal community composition. Consequently, straw returning can improve soil fertility and maintain ecosystem health.


Assuntos
Micobioma , Oryza , Agricultura , Ecossistema , Fertilizantes/análise , Rotação , Solo , Microbiologia do Solo
8.
Ying Yong Sheng Tai Xue Bao ; 31(6): 1889-1897, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34494741

RESUMO

Climate change has profound impacts on the structure and function of forest ecosystem. Under the background of climate warming, the growth patterns and climate responses of different species in different environments determine the development and stability of ecosystems. Using the method of tree chronology with ring width data of Betula platyphylla in Oakley Mountain of Daxing'an Mountains, we examined the relationship between the growth climate response of the pioneer B. platyphylla in larch forest and temperature rise and altitudinal changes. The results showed that climate warming resulted in the differentiation on B. platyphylla in different altitude. The radial growth of B. platyphylla increased significantly at the low altitude area (1050 m), while there were little changes at the relatively high altitude area (1250 m). Before the time of rapid warming (1980), the radial growth of B. platyphylla on two altitude areas were significantly stressed by low temperature in winter (October to February). During the period of rapid warming (1981-2010), low temperature stress in winter did not affect tree growth, with the growing season (May to July) temperature becoming the main limiting factors to the radial growth of B. platyphylla at the relatively high altitude areas. The growth of B. platyphylla increased in the low altitude stands with favorable water and heat conditions. The distribution of B. platyphylla may generally spread to high altitude sites in the study area under climate warming.


Assuntos
Betula , Ecossistema , Altitude , China , Mudança Climática , Florestas , Árvores
9.
Biomed Environ Sci ; 33(11): 821-828, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33771235

RESUMO

OBJECTIVE: To explore the effects of prenatal exposure to polybrominated diphenyl ethers (PBDEs) on placental size and birth outcomes. METHODS: Based on the perspective Wenzhou Birth Cohort, this nested case-control study included 101 fetal growth restriction (FGR) and 101 healthy newborns. Maternal serum samples were collected during the third trimester and measured for PBDEs by gas chromatography tandem mass spectrometry. The basic information of mother-newborn pairs was collected from questionnaires, whereas the placental size and birth outcomes of newborns were obtained from hospital records. RESULTS: A total of 19 brominated diphenyle ether (BDE) congeners were detected in maternal serum samples. Higher concentrations of BDE-207, -208, -209, and ∑ 19PBDEs were detected in FGR cases than in controls. Increased BDE-207, -208, -209, and ∑ 19PBDEs levels in maternal serum were related to decreased placental length, breadth, surface area, birth weight, birth length, gestational age, and Quetelet index of newborns. After adjusting for confounders, BDE-207 and ∑ 19PBDE concentrations in maternal serum were significantly associated with an increased risk of FGR. CONCLUSION: A negative association was found between PBDE levels in maternal serum and placental size and birth outcomes. Prenatal PBDE exposure may be associated with elevated risk of the incidence of FGR birth.


Assuntos
Retardo do Crescimento Fetal/epidemiologia , Éteres Difenil Halogenados/sangue , Placenta/fisiologia , Estudos de Casos e Controles , China/epidemiologia , Feminino , Retardo do Crescimento Fetal/induzido quimicamente , Humanos , Incidência , Recém-Nascido , Gravidez , Fatores de Risco
10.
World J Clin Pediatr ; 8(2): 23-32, 2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-31065543

RESUMO

Necrotizing enterocolitis (NEC) is among the most common and devastating diseases encountered in premature infants, yet the true etiology continues to be poorly understood despite decades of research. Recently, gut bacterial dysbiosis has been proposed as a risk factor for the development of NEC. Based on this theory, several best clinical practices designed to reduce the risk of NEC have been proposed and/or implemented. This review summarizes the results of recent clinical trials and meta-analyses that support some of the existing clinical practices for reducing the risk of NEC in premature infants. It is evident that human milk feeding can reduce the incidence of NEC. While most of the studies demonstrated that probiotic supplementation can significantly reduce the incidence of NEC in premature infants, there are still some concerns regarding the quality, safety, optimal dosage, and treatment duration of probiotic preparations. Antibiotic prophylaxis does not reduce the incidence of NEC, and prolonged initial empirical use of antibiotics might in fact increase the risk of NEC for high-risk premature infants. Lastly, standardized feeding protocols are strongly recommended, both for prevention of postnatal growth restriction and NEC.

11.
J Anal Methods Chem ; 2018: 5890140, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29629212

RESUMO

There are many PCR-based methods for animal species identification; however, their detection numbers are limited or could not identify unknown species. We set out to solve this problem by developing a universal primer PCR assay for simultaneous identification of eight animal species, including goat, sheep, deer, buffalo, cattle, yak, pig, and camel. In this assay, the variable lengths of mitochondrial DNA were amplified using a pair of universal primers. PCR amplifications yielded 760 bp, 737 bp, 537 bp, 486 bp, 481 bp, 464 bp, 429 bp, and 359 bp length fragments for goat, sheep, deer, buffalo, cattle, yak, pig, and camel, respectively. This primer pair had no cross-reaction with other common domestic animals and fish. The limit of detection varied from 0.01 to 0.05 ng of genomic DNA for eight animal species in a 20 µl PCR mixture. Each PCR product could be further digested into fragments with variable sizes and qualitative analysis by SspI restriction enzyme. This developed PCR-RFLP assay was sufficient to distinguish all targeted species. Compared with the previous published related methods, this approach is simple, with high throughput, fast processing rates, and more cost-effective for routine identification of meat in foodstuffs.

12.
Mol Med Rep ; 14(4): 2929-36, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27510750

RESUMO

The sonic hedgehog (SHH) morphogen regulates cell differentiation and controls a number of genes during renal morphogenesis. To date, the effects of SHH on fibroblast growth factors (Fgfs) in embryonic kidney development remain unclear. In the present study, explants of BALB/c mouse embryonic kidney tissues were used to investigate the role of exogenous SHH on Fgf8 and Fgf10 expression levels ex vivo. Ureteric bud branches and epithelial metanephric derivatives were used to determine the renal morphogenesis with Dolichos biflorus agglutinin or hematoxylin­eosin staining. mRNA expression levels were determined using reverse transcription­quantitative polymerase chain reaction, while the protein expression levels were examined using immunohistochemistry and western blot analysis. During the initial stages of metanephric development, low levels of SHH, Fgf8, and Fgf10 expression were observed, which were found to increase significantly during more advanced stages of metanephric development. In addition, exogenous SHH protein treatment increased the number of ureteric bud branches and enhanced the formation of nephrons. Exogenous SHH reduced the Fgf8 mRNA and protein expression levels, whereas cyclopamine (an SHH­smoothened receptor inhibitor) interfered with SHH­mediated downregulation of Fgf8 expression. By contrast, exogenous SHH protein was not found to modulate Fgf10 mRNA and protein expression levels. In conclusion, these results indicate that the modulatory effects of SHH on BALB/c mouse metanephric explant cultures may involve the regulation of Fgf8 expression but not Fgf10 expression, which provides evidence for the functional role of Fgf proteins in renal morphogenesis.


Assuntos
Fator 8 de Crescimento de Fibroblasto/genética , Regulação Enzimológica da Expressão Gênica , Proteínas Hedgehog/metabolismo , Rim/embriologia , Animais , Feminino , Fator 10 de Crescimento de Fibroblastos/análise , Fator 10 de Crescimento de Fibroblastos/genética , Fator 8 de Crescimento de Fibroblasto/análise , Rim/metabolismo , Camundongos Endogâmicos BALB C , RNA Mensageiro/análise , RNA Mensageiro/genética
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