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1.
J Org Chem ; 89(5): 3672-3676, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38379290

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-38179934

ABSTRACT

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.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1009353

ABSTRACT

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.


Subject(s)
Humans , Blood Group Antigens/genetics , Genotype , Genotyping Techniques , Heterozygote , Alleles , Blood Donors , Rh-Hr Blood-Group System/genetics
5.
Huan Jing Ke Xue ; 44(4): 1933-1942, 2023 Apr 08.
Article in Chinese | MEDLINE | ID: mdl-37040944

ABSTRACT

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.

6.
J Phys Condens Matter ; 35(27)2023 Apr 12.
Article in English | MEDLINE | ID: mdl-37011631

ABSTRACT

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.

7.
Org Lett ; 25(9): 1375-1379, 2023 Mar 10.
Article in English | MEDLINE | ID: mdl-36854113

ABSTRACT

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.

8.
Huan Jing Ke Xue ; 44(1): 11-19, 2023 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-36635790

ABSTRACT

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.


Subject(s)
Air Pollutants , Air Pollution , Air Pollutants/analysis , Air Pollution/analysis , Particulate Matter/analysis , Seasons , Environmental Monitoring/methods , Aerosols/analysis , China
10.
Article in English | MEDLINE | ID: mdl-36572142

ABSTRACT

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.


Subject(s)
Cyprinidae , Diet , Animals , Cyprinidae/physiology , Antioxidants/metabolism , Oxidative Stress , Glutathione/metabolism , Apoptosis , Fish Proteins/metabolism
11.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-990859

ABSTRACT

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.

12.
Acta Pharmaceutica Sinica B ; (6): 1740-1754, 2023.
Article in English | WPRIM (Western Pacific) | ID: wpr-982796

ABSTRACT

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.

13.
Theriogenology ; 193: 30-36, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36126363

ABSTRACT

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.


Subject(s)
Blastocyst , Fertilization in Vitro , Animals , Cats , Culture Media , Embryo Transfer/veterinary , Female , Fertilization in Vitro/veterinary
14.
J Phys Condens Matter ; 34(41)2022 Aug 04.
Article in English | MEDLINE | ID: mdl-35896108

ABSTRACT

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.

15.
Org Biomol Chem ; 20(24): 4837-4845, 2022 06 22.
Article in English | MEDLINE | ID: mdl-35635524

ABSTRACT

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.


Subject(s)
Transition Elements , Catalysis , Cyclization , Maleimides/chemistry , Molecular Structure , Transition Elements/chemistry
16.
Huan Jing Ke Xue ; 43(4): 1706-1715, 2022 Apr 08.
Article in Chinese | MEDLINE | ID: mdl-35393794

ABSTRACT

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.


Subject(s)
Environmental Monitoring , Metals, Heavy , Adult , Child , China , Environmental Pollution/analysis , Humans , Lead/analysis , Metals, Heavy/analysis , Particulate Matter/analysis , Risk Assessment
17.
Fish Physiol Biochem ; 48(1): 263-274, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35099685

ABSTRACT

Blunt snout bream plays an important role in freshwater aquaculture in China, but the development of its culture industry has been restricted by increasing hypoxia problem. Through the breeding of wild blunt snout bream populations (F0), a hypoxia-tolerant new variety (F6) was obtained. In this study, the new variety was stressed under low oxygen concentration (2.0 mg·L-1) for 4 and 7 days, the morphological structure of the gill tissue showed a striking change, the interlamellar cell mass (ILCM) volume reduced significantly (P < 0.05), and the lamellar respiratory surface area enlarged significantly (P < 0.05), compared to normoxic controls. After 7 days of oxygen recovery, gill remodeling was completely reversed. Additionally, the TUNEL-positive apoptotic fluorescence signals increased in the gills exposed to hypoxia up to 4 and 7 days; the apoptosis rate also increased significantly (P < 0.05). Under 4 and 7 days of hypoxia stress, the expression of anti-apoptotic gene Bcl-2 in the gills downregulated significantly (P < 0.05), with the significantly (P < 0.05) upregulated expression of pro-apoptotic gene Bad. Furthermore, under hypoxia stress, the activity or content of oxidative stress-related enzymes (superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and glutathione (GSH)) in gill tissue increased to varying degrees compared to normoxic controls. These results offer a new perspective into the cellular and molecular mechanism of hypoxia-induced gill remodeling in blunt snout bream and a theoretical basis for its hypoxia adaptation mechanism.


Subject(s)
Cyprinidae , Cypriniformes , Gills , Hypoxia , Oxygen/physiology , Animals , Apoptosis , Cyprinidae/metabolism , Cypriniformes/metabolism , Fish Proteins/metabolism , Gills/metabolism , Hypoxia/veterinary , Oxidative Stress
18.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1004136

ABSTRACT

【Objective】 To study the molecular mechanism of 9 samples with rare RhD variants and their RhD epitopes and protein structure. 【Methods】 The 9 blood samples with rare RhD variants were collected from 210 644 blood donors of Shenzhen Blood Center. Regular serological assaying was used for determination of Rh type for the 9 samples. Indirect anti-human globulin test (IAT) was used to confirm the RhD antigen and to screen the antibodies. D-screen reagent was sued to analyze the RhD epitopes of the samples. RHD zygosity testing of the samples was detected by PCR-SSP. The nucleotide sequences of all 9 exons and adjacent flanking intron regions of RHD gene were sequenced. The prediction of the effects of mutations on RhD protein function were analyzed using PROVEAN, SIFT, PolyPhen-2 and MutationTaster software. Robetta and Swiss-PdbViewer 4.1.0 were used for modeling the tertiary structures of RhD. 【Results】 A total of 9 individuals with rare RhD variants were identified as follows: RHD*weak D type 25, RHD*weak D type 50, RHD*weak D type 95, RHD*weak D type 12, RHD*weak D type 128 and four novel RHD alleles. The prediction of the tertiary structures showed that the RhD protein conformation was disrupted in the 9 rare RhD variants samples. 【Conclusion】 Five rare and four novel RHD alleles have been identified. Their phenotypic and genotypic descriptions enrich the database of reported RHD alleles. Bioinformatics analysis provided evidences for further study of the structure and functions of RhD protein.

19.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1004106

ABSTRACT

【Objective】 To investigate the family inheritance of α-Thalassemla gene and the risk of severe anemia in neonates caused by cold IgG anti-M. 【Methods】 ABO, Rh, MN blood groups and the specificity of unexpected antibody were identified by blood group serology. The IgG subtype and antibody titer of anti-M antibody were detected. The etiology of neonatal hemolytic disease was identified by three tests and α-Thalassemla gene diagnosis. 【Results】 Family investigation showed that father was B, CCDee, MN with no α-Thalassemla gene detected; Mother B, CcDee, NN, carrying α-Thalassemla gene; both the proband and his brother were B, CCDee, MN, carrying α-Thalassemla gene. Cold IgG anti-M was present in plasma of both the mother and the proband. The titer of the mother was 128 and that of the proband was 64. The subtype of IgG anti-M was IgG1 and IgG3. The direct anti-globulin test, release test and free test of the proband and his brother were negative, and the diagnosis was severe anemia and hemolysis caused by α-Thalassemla combined with cold IgG anti-M. 【Conclusion】 The direct antiglobulin test of neonatal hemolytic disease caused by IgG anti-M can be negative or weakly positive, and α-Thalassemla gene could be hereditary in families. The presence of α-Thalassemla gene can cause anemia, hemolysis and splenomegalysis in neonates, which could be aggravated when accompanied by cold-type IgG anti-M. In the presence of high-valency IgG antibody in plasma, blood exchange combined with transfusion can improve the curative effect.

20.
Article in English | WPRIM (Western Pacific) | ID: wpr-920657

ABSTRACT

@#Au nanoplates (Au NPLs), a kind of novel two-dimensional metal materials with nanometer scale thickness, have attracted much attention due to their excellent properties; and have been widely used in the fields of tumor diagnosis and treatment in recent years.This article introduces the characteristics and preparation methods of Au nanoplates and summarizes their application in tumor diagnosis and treatment in recent years, in order to provide reference and ideas for the research and application of Au nanoplates in tumor.

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