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1.
J Org Chem ; 89(5): 3672-3676, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38379290

RESUMO

The Rh(III)-catalyzed annulation of benzoic acids with nitroalkenes was disclosed to afford a wide range of 3,4-disubstituted isochroman-1-ones with excellent regioselectivity and high catalytic efficiency. Both aromatic and aliphatic nitroalkenes participated in this cyclization reaction successfully. The synthetic value of 3,4-disubstituted isochroman-1-ones was proven by a series of derivatizations. Furthermore, a reliable mechanism is outlined on the basis of experimental investigations and related precedents.

2.
Org Lett ; 26(2): 536-541, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38179934

RESUMO

In the presence of visible light irradiation, organophoto/nickel dual catalysts, and the mild base K2HPO4, 1,3-enynes react with silanecarboxylic acids to give the corresponding α-silylallenes with high selectivity. In this uniquely decarboxylative hydrosilylation of 1,3-enynes, a silyl radical process is involved and diverse electron-rich and -poor substrates proceed smoothly in moderate to excellent yields. This transformation is particularly synthetically worthwhile when using MeOD as the solvent, which furnishes new access to α-silyldeuteroallenes.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1039498

RESUMO

【Objective】 To establish a method for qualitative detection of the presence or absence of all KIR genes by quantitative polymerase chain reaction(Q-PCR). 【Methods】 Based on the polymorphism of high-resolution level KIR alleles in Chinese population and the IPD-KIR database, KIR gene-specific primers were designed to amplify all the 16 KIR genes and 2DS4-Normal and 2DS4-Deleted subtypes by Q-PCR. Meanwhile, one negative control and one positive control specific amplifying human growth hormone (HGH) gene fragment were set to monitor the false positive and false negative results in PCR amplification, respectively. A total of 302 samples with known KIR genotype previously identified by KIR PCR-SSP commercial kit were randomly selected for blind inspection to verify the reliability of KIR Q-PCR method established by authors. 【Results】 The results of 300 samples detected by our KIR Q-PCR method were consistent with the known results, but two samples showed inconsistent results. One sample was negative for 2DS5 by Q-PCR but positive by PCR-SSP, another sample was positive for 2DS1 by Q-PCR but negative by PCR-SSP. The two doubtful samples were genotyped by sequencing-based typing (PCR-SBT) for 2DS5 and 2DS1, respectively. PCR-SBT results confirmed that the results of Q-PCR test was correct. 【Conclusion】 The KIR Q-PCR method established in this paper can provide accurate and reliable results for testing the presence or absence of KIR genes.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1017795

RESUMO

Objective To explore the machine learning model and risk factor analysis for hospital infection caused by carbapenem-resistant enterobacteriaceae(CRE).Methods The clinical data of totally 451 patients infected with extended-spectrum β-lactamases(ESBL)producing Enterobacteriaceae treated in the hospital from 2018 to 2022 were retrospectively collected.The patients were divided into CRE group(115 cases)and sensitive group(336 cases)according to the susceptibility of carbapenem.Four machine learning methods in-cluding Logistic regression analysis,random forest,support vector machine,and neural network were used to build prediction models and receiver operating characteristic curve was used to evaluate.Based on the predic-tion model with the best performance,risk factors for CRE infection were analyzed.Results Random forest model had the best performance,with the area under the curve of 0.952 3.The risk factors for predicting CRE infection by the random forest model included 15 clinical data items,namely fever for more than 3 days,cere-bral injury,drainage fluid sample,trunk surgery,first-level or special-level nursing,ICU treatment,procalcito-nin,anti-anaerobic bacteria,the use of third-generation cephalosporins,age,pre-albumin,creatinine,white blood cell count,and albumin.Conclusion The CRE prediction model developed in this study has good predic-tive value and the risk factors have guiding significance for the early prevention and treatment of CRE infec-tion in clinical practice.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1009353

RESUMO

OBJECTIVE@#To develop a genotyping method for the Junior blood type and report on a rare blood type with Jr(a-).@*METHODS@#Healthy O-type RhD+ volunteer donors of the Shenzhen Blood Center from January to May 2021 (n = 1 568) and a pedigree with difficult cross-matching (n = 3) were selected as the study subjects. Serological methods were used for proband's blood type identification, unexpected antibody identification, and antibody titer determination. Polymerase chain reaction-sequence specific primer (PCR-SSP) method was used for typing the proband's RhD gene. ABCG2 gene coding region sequencing and a PCR-SSP genotyping method were established for determining the genotypes of the proband and his family members and screening of Jra antigen-negative rare blood type among the 1 568 blood donors.@*RESULTS@#The proband's ABO and RhD blood types were respectively determined as B and partial D (RHDDVI.3/RHD01N.01), Junior blood type Jra antigen was negative, and plasma had contained anti-D and anti-Jra. Sequencing of the ABCG2 gene revealed that the proband's genotype was ABGG201N.01/ABGG201N.01 [homozygous c.376C>T (p.Gln126X) variants], which is the most common Jr(a-) blood type allele in the Asian population. Screening of the voluntary blood donors has detected no Jr(a-) rare blood type. Statistical analysis of the heterozygotes suggested that the allelic frequency for ABCG2*01N.01 (c.376T) was 0.45%, and the frequency of Jr(a-) rare blood type with this molecular background was about 0.2‰.@*CONCLUSION@#A very rare case of partial DVI.3 type and Jr(a-) rare blood type has been identified. And a method for identifying the Junior blood type through sequencing the coding regions of the ABCG2 gene and PCR-SSP has been established.


Assuntos
Humanos , Antígenos de Grupos Sanguíneos/genética , Genótipo , Técnicas de Genotipagem , Heterozigoto , Alelos , Doadores de Sangue , Sistema do Grupo Sanguíneo Rh-Hr/genética
6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1019926

RESUMO

Objective To analyze the correlation between the expression of soluble glycoprotein A(GPA)in plasma of healthy blood donors and anti-M and anti-"Mia"antibodies.Methods Plasma from healthy donors from February 9,2022 to February 15,2023 was collected:irregular antibody-negative NN type(group Ⅰ,n=118)and MM type(group Ⅱ,n=51),anti-M antibody positive NN type(group Ⅲ,n=145)and anti-"Mia"antibody positive companion type(group Ⅳ,n= 87),the GPA content in plasma of different individuals in 4 groups was detected,and the difference in GPA expression was analyzed by t-test.Results The average plasma GPA contents in groupsⅠ,Ⅱ,Ⅲ and Ⅳ were 9.941±0.252,10.97±0.256,5.139±0.129 and 4.28±0.139ng/ml,respectively.The average GPA content of groups Ⅰ and Ⅱ was higher,and the average GPA content of groups Ⅲ and Ⅳ was lower,and the differences were statistically significant(all P<0.01).Conclusion The GPA content in plasma of healthy donors with anti-M and anti-"Mia"antibodies was significantly lower than that of the antibody-negative group.The results of this study lay a foundation for further investigation of whether GPA in plasma has the ability to neutralize anti-M and anti-"Mia"antibodies,improve disease diagnosis and safe blood transfusion.

8.
Huan Jing Ke Xue ; 44(4): 1933-1942, 2023 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-37040944

RESUMO

In order to explore the pollution characteristics and sources of atmospheric volatile organic compounds (VOCs) in winter in Kaifeng City, based on the atmospheric VOCs component data obtained from the online monitoring station of the Kaifeng Ecological and Environmental Bureau (Urban Area) from December 2021 to January 2022, the pollution characteristics of VOCs and secondary organic aerosol formation potential (SOAP) were discussed, and the sources of VOCs were analyzed by using the PMF model. The results showed that the average mass concentration of VOCs in winter in Kaifeng City was (104.71±48.56) µg·m-3, and alkanes (37.7%) had the highest proportion of mass concentrations, followed by that of halohydrocarbons (23.5%), aromatics (16.8%), OVOCs (12.6%), alkenes (6.9%), and alkynes (2.6%). The averaged total SOAP contributed by VOCs was 3.18 µg·m-3, of which aromatics contributed as much as 83.8%, followed by alkanes (11.5%). The largest anthropogenic source of VOCs in winter in Kaifeng City was solvent utilization (17.9%), followed by fuel combustion (15.9%), industrial halohydrocarbon emission (15.8%), motor vehicle emission (14.7%), organic chemical industry (14.5%), and LPG emission (13.3%); solvent utilization contributed 32.2% of the total SOAP, followed by motor vehicle emission (22.8%) and industrial halohydrocarbon emission (18.9%). It was found that reducing VOCs emissions from solvent utilization, motor vehicle emission, and industrial halohydrocarbon emission was important to control the formation of secondary organic aerosols in winter in Kaifeng City.

9.
J Phys Condens Matter ; 35(27)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37011631

RESUMO

This study is started from a photon-magnon model with a competition effect of the level attraction and repulsion, its Hermiticity is mainly decided by a phase-dependent and asymmetric coupling factor, namelyφ = 0 for Hermitian andϕ=πfor non-Hermitian. Then an extensional study predicts the quantum critical behaviors using an Hermitian and even no-Hermitian photon-spins model with an additional second-order drive. The numerical results firstly indicate that this coupling phaseφcan function the protective effect on quantum phase transitions (QPTs), and the new tricritical points can not only be modulated by this nonlinear drive, but also be influenced by the dissipation and the collective decoherence. Secondly, this competition effect can also induce a reversal of the value of order parameters between the positive and negative. This study can also bring more important results of QPTs toward the issue of symmetry breaking and non-Hermiticity.

10.
Org Lett ; 25(9): 1375-1379, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36854113

RESUMO

The Rh(III)-catalyzed addition of the indole C2-H bond to nitroalkenes under an ambient atmosphere is disclosed, providing direct access to a wide range of 2-(2-nitroalkyl)indoles (33 examples) with excellent chemo- and regioselectivity. In addition, pyrrole derivatives also successfully participated in this Friedel-Crafts alkylation reaction. Representative nitroalkane products could be converted into structurally diverse and valuable indole derivatives. Furthermore, a series of control experiments were conducted, and a plausible mechanism was proposed.

12.
Huan Jing Ke Xue ; 44(1): 11-19, 2023 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-36635790

RESUMO

In recent years, the Beijing-Tianjin-Hebei region and its surrounding areas have experienced multiple haze pollution processes. Owing to the limitation of observational instruments, there has not been a comparative study of haze pollution between urban and rural areas in northern Henan province. A series of high-time-resolution instruments were used during a regional heavy pollution process (January 12-25, 2018) at two urban sites and three rural sites. The results showed that SO42-, NO-3, and NH+4 (SNA) were the components with the highest proportion in PM2.5 at the five sites during the haze event with a range of 53%-63%, of which nitrate was the most important, accounting for 24%-32%, followed by sulfate, ranging from 13%-17%. Compared with urban sites, rural sites were more affected by organic matter, especially at night. With the aggravation of pollution, the proportion of SNA increased, reaching 67% during periods of heavy pollution. When the area was affected by the air mass transported from the south, the proportion of NO-3 in PM2.5 increased, and when the area was affected by the air transport in the north, the proportions of SO42- and organic matter increased. Ammonium nitrate was the most important component that led to the decrease in atmospheric visibility during the haze process. Moreover, the contributions of ammonium nitrate and ammonium sulfate at the urban sites were higher than those at the rural sites. To summarize, there were significant differences in PM2.5 components between the urban and rural sites. Urban areas need to continue to strengthen the reduction in gaseous precursors, and rural areas need to pay attention to the sources of carbonaceous aerosol.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Material Particulado/análise , Estações do Ano , Monitoramento Ambiental/métodos , Aerossóis/análise , China
13.
Artigo em Inglês | MEDLINE | ID: mdl-36572142

RESUMO

A new hypoxia-tolerant variety of blunt snout bream was obtained by successive breeding of the wild population, which markedly improved hypoxia tolerance. In this study, the hypoxia-tolerant variety was exposed to hypoxia (2.0 mg O2·L-1) for 4, 7 days. The contents of blood biochemical indicators including the number of red blood cells (RBC), total cholesterol (T-CHO), total protein (TP), triglyceride (TG), glucose (GLU), and lactic acid (LD) increased significantly (P < 0.05) under hypoxia. The glycogen content in the liver and muscle decreased significantly (P < 0.05) and the LD content in the brain, muscle and liver increased significantly (P < 0.05) under hypoxia. The levels of oxidative stress-related indicators i.e., superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), catalase (CAT), and total antioxidant capacity (T-AOC) also changed significantly (P < 0.05) in the heart, liver, and intestine of the new variety under hypoxia. Additionally, hypoxia has caused injuries to the heart, liver, and intestine, but it shows amazing repair ability during reoxygenation. The apoptotic cells and apoptosis rate in the heart, liver, and intestine increased under hypoxia. Under hypoxia, the expression of the B-cell lymphomas 2 (Bcl-2) gene in the heart, liver, and intestine was significantly (P < 0.05) down-regulated, while the expression of the BCL2-associated agonist of cell death (Bad) gene was significantly (P < 0.05) up-regulated. These results are of great significance for enriching the basic data of blunt snout bream new variety in response to hypoxia and promoting the healthy development of its culture industry.


Assuntos
Cyprinidae , Dieta , Animais , Cyprinidae/fisiologia , Antioxidantes/metabolismo , Estresse Oxidativo , Glutationa/metabolismo , Apoptose , Proteínas de Peixes/metabolismo
14.
Acta Pharmaceutica Sinica B ; (6): 1740-1754, 2023.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-982796

RESUMO

Cancer immunotherapy has become a promising strategy. However, the effectiveness of immunotherapy is restricted in "cold tumors" characterized with insufficient T cells intratumoral infiltration and failed T cells priming. Herein, an on-demand integrated nano-engager (JOT-Lip) was developed to convert cold tumors to hot via "increased DNA damage and dual immune checkpoint inhibition" strategy. JOT-Lip was engineered by co-loading oxaliplatin (Oxa) and JQ1 into liposomes with T-cell immunoglobulin mucin-3 antibodies (Tim-3 mAb) coupled on the liposomal surface by metalloproteinase-2 (MMP-2)-sensitive linker. JQ1 inhibited DNA repair to increase DNA damage and immunogenic cell death (ICD) of Oxa, thus promoting T cells intratumoral infiltration. In addition, JQ1 inhibited PD-1/PD-L1 pathway, achieving dual immune checkpoint inhibition combining with Tim-3 mAb, thus effectively promoting T cells priming. It is demonstrated that JOT-Lip not only increased DNA damage and promoted the release of damage-associated molecular patterns (DAMPs), but also enhanced T cells intratumoral infiltration and promoted T cell priming, which successfully converted cold tumors to hot and showed significant anti-tumor and anti-metastasis effects. Collectively, our study provides a rational design of an effective combination regimen and an ideal co-delivery system to convert cold tumors to hot, which holds great potential in clinical cancer chemoimmunotherapy.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-990859

RESUMO

Corneal refractive surgery is widely used to correct myopia and astigmatism because of its safety, effectiveness and stability.Precision medicine is the future direction of development, and the demands for accuracy in corneal refractive surgery are also increasing, which has a direct impact on patient satisfaction.Nomogram, as a key design in refractive surgery, needs to be combined with several important predictors to quantify individual risk.Different surgical methods need different nomograms.In this paper, the effects of corneal surface surgery, lamellar surgery, modeling algorithm and possible factors such as patient's sex, age, expected correction, corneal curvature, preoperative spherical equivalent, etc.on the predicted values were discussed.At the same time, the application of nomograms in corneal refractive surgery at home and abroad in recent years and the research progress of nomogram influencing factors were explored, in order to provide more and more accurate reference for clinical practice, to improve the accuracy of corneal refractive surgery and help patients achieve satisfactory postoperative visual quality.

16.
Chinese Journal of Neonatology ; (6): 721-726, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1022532

RESUMO

Objective:To explore the genotype and clinical phenotype characteristics of patients with pancreatic agenesis caused by GATA6 gene mutations and to improve the clinical understanding of pancreatic agenesis.Methods:The clinical data of a newborn with pancreatic agenesis admitted to the Second Hospital of Shandong University were retrospectively analyzed. Relevant literature published until October 31, 2022, were retrieved from China National Knowledge Infrastructure, Wanfang Database, VIP Database, Chinese Medical Journal Full Text Database, PubMed, Embase and SCI Database with the terms of "pancreatic agenesis", "GATA6", "pancreatic agenesis/hypoplasia" and "GATA6 Translation Factor". The characteristics of gene variants and clinical manifestations of patients diagnosed with pancreatic agenesis caused by GATA6 gene mutation were retrieved and summarized.Results:This case was a full-term male infant who developed insulin dependent hyperglycemia and fatty diarrhea 2 d after birth, accompanied by intrauterine growth restriction, congenital heart disease, and cryptorchidism. Genetic testing showed a novel heterozygous mutation of GATA6 (c.1366C>T) which was consistent with the autosomal dominant inheritance pattern. The phenotype and genotype between the proband and his parents were consistent with the cosegregation. The ACMG mutation was rated as pathogenic variant. Intravenous infusion of insulin, subcutaneous injection of insulin, or long-acting insulin were not effective. After continuous subcutaneous pumping of aspartic insulin combined with oral pancreatic enzyme replacement therapy, the infant's condition was improved and discharged. Follow up to age of 15 months, the patient still relied on continuously subcutaneous pump to control blood glucose, pancreatic exocrine function was back to normal, and the development was generally normal. A total of 59 cases were reported in 22 articles, with the case from our hospital, there were 60 patients in total. Among them, 47 were probands and 13 were family members, about 61.7% (29/47) of which were de novo mutations. There were 39 variants, of which 28.2% (11/39) were missense mutations and 71.8% (28/39) were functional deletion variations. Mutations of GATA6 gene had a broad phenotype spectrum. The phenotypes mainly included neonatal diabetes mellitus ( n=39) and pancreatic exocrine insufficiency ( n=39). Other extra-pancreatic features included different types of congenital heart disease ( n=54), congenital biliary abnormalities ( n=23), intestinal developmental disorders ( n=16), neurocognitive disorders ( n=18) and endocrine abnormalities ( n=15). Conclusions:The heterozygous variations of GATA6 gene lead to pancreatic hypoplasia and a broad phenotype spectrum. The pancreatic phenotypes mainly include neonatal diabetes mellitus and pancreatic exocrine insufficiency, and extra-pancreatic phenotypes include congenital heart disease and other developmental abnormalities.

17.
Theriogenology ; 193: 30-36, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36126363

RESUMO

Transcervical transplantation of embryos has been wildly used in several species. However, it has not been successful in feline species because of their unique cervix structure combined with poor in vitro culture systems for embryos. In the present study, a simple device to guide the embryo transfer (ET) tube through the cervix and into the uterus was developed. To supply better blastocysts for ET, the in vitro culture system of feline embryos was also optimized. Results showed that 91.67 ± 4.17% of embryos developed to the blastocyst stage in QAU-4 medium compared with 49.17 ± 6.51% in KSOM medium. The total cell number of blastocysts reached 87.1 ± 22.1 in QAU-4 medium compared with 29.8 ± 2.1 in KSOM. Embryoid body formation was also observed in QAU-4 medium. Finally, by the improved technical scheme, CRX (Cone-Rod Homeobox) gene-edited kittens were successfully bred. To date, this is the first report, to our knowledge, of knockout kittens successfully delivered after transcervical ET with a simple transfer tube.


Assuntos
Blastocisto , Fertilização in vitro , Animais , Gatos , Meios de Cultura , Transferência Embrionária/veterinária , Feminino , Fertilização in vitro/veterinária
18.
J Phys Condens Matter ; 34(41)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35896108

RESUMO

A proposal for simulating the Dicke-Lattice model in a mechanics-controlled hybrid quantum system is studied here. An array of coupled mechanical resonators (MRs) can homogeneously interact with a group of trapped Bose-Einstein condensates (BECs) via the gradient magnetic field induced by the oscillating resonators. Assisted by the classical dichromatic radio-wave fields, each subsystem with the BEC-MR interaction can mimic the Dicke type spin-phonon interaction, and the whole system is therefore extended to a lattice of Dicke models with the additional adjacent phonon-phonon hopping couplings. In view of this lattice model with theZ2symmetry, its quantum phase transitions behavior can be controlled by this periodic phonon-phonon interactions in the momentum space. This investigation may be considered as a fresh attempt on manipulating the critical behaviors of the collective spins through the external mechanical method.

19.
Org Biomol Chem ; 20(24): 4837-4845, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35635524

RESUMO

Transition-metal-catalyzed directed C-H alkenylation with maleimides has attracted much attention in recent years, as maleimide core moieties are present in various natural products and pharmaceuticals. In addition, these derivatives can be readily modified into biologically important compounds including succinimides, pyrrolidines and γ-lactams. The efficient chelation-assisted inert C-H bond activation strategy provides straightforward access to a wide array of structurally diverse molecules containing maleimide units. This review describes the major progress and mechanistic investigations on Heck-type reaction/cyclization of maleimides with organic molecules until early 2022.


Assuntos
Elementos de Transição , Catálise , Ciclização , Maleimidas/química , Estrutura Molecular , Elementos de Transição/química
20.
Huan Jing Ke Xue ; 43(4): 1706-1715, 2022 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-35393794

RESUMO

In order to study the pollution characteristics and sources of heavy metals in urban atmospheric PM2.5, 21 elements in atmospheric PM2.5 in Zhengzhou City were detected using an online metal analyzer during July and October 2017 and January and April 2018, and the changes in heavy metal concentrations were analyzed. Heavy metals were traced by enrichment factors, principal component analysis, and potential source function. The US EPA risk assessment model was used to assess their health risks. The results showed that:the concentrations of K, Zn, Mn, Pb, Cu, As, Cr, and Se increased with the increase in pollution level. The results of enrichment factors and principal component analysis showed that the main sources of heavy metals were crust, mixed combustion, industry, and motor vehicles. The characteristic radar charts showed that the pollution dominated by crustal sources mainly occurred in spring and winter, whereas the pollution dominated by mixed combustion sources mainly occurred in winter. Pb, As, and Ni were greatly affected by the transport of a fen nutrient-laden plain, Beijing-Tianjin-Hebei, and southern Henan, whereas Cd was greatly affected by the northwest region of the sampling site. As presented a significant carcinogenic risk in both adults and children, whereas Pb and Sb presented a significant non-carcinogenic risk in children.


Assuntos
Monitoramento Ambiental , Metais Pesados , Adulto , Criança , China , Poluição Ambiental/análise , Humanos , Chumbo/análise , Metais Pesados/análise , Material Particulado/análise , Medição de Risco
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