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1.
J Am Chem Soc ; 146(1): 723-732, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38116993

RESUMO

Despite the current progress achieved in asymmetric hydroacylations, highly enantioselective catalytic addition of unfunctionalized aldehydes to internal alkenes remains an unsolved challenge. Here, using a coordination-assisted strategy, we developed a rhodium-catalyzed regio- and enantioselective addition of unfunctionalized aldehydes to internal alkenes such as enamides and ß,γ-unsaturated amides. Valuable α-amino ketones and 1,4-dicarbonyl compounds were directly obtained with high enantioselectivity from readily available materials.

2.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36499094

RESUMO

The current global pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) of COVID-19 has infected hundreds of millions of people, killed millions, and continues to pose a threat. It has become one of the largest epidemics in human history, causing enormous damage to people's lives and economies in the whole world. However, there are still many uncertainties and continued attention to the impact of SARS-CoV-2 on human health. The entry of SARS-CoV-2 into host cells is facilitated by the binding of the spike protein on the virus surface to the cell surface receptor angiotensin-converting enzyme 2 (ACE2). Furthermore, transmembrane protease serine 2 (TMPRSS2) is a host surface protease that cleaves and proteolytically activates its S protein, which is necessary for viral infection. Thus, SARS-CoV-2 uses the ACE2 receptor for cell entry and initiates the S protein using the protease TMPRSS2. Schizophyllum commune (SC) is one of the most widely distributed fungi, often found on the rotten wood of trees that has been found to have various health benefits, including anticancer, antimicrobial activity, antiparasitic, and immunomodulatory function. In this article, SC significantly diminished the expression ACE2 and TMPRSS2 protein in vitro and in vivo without cell damage. In addition, adenosine from SC was also proven in this experiment to reduce the ACE2 and TMPRSS2 expression. Thus, our findings suggest that SC and adenosine exhibit potential for the repression of SARS-CoV-2 infection via the ACE2 and TMPRSS2 axis.


Assuntos
Enzima de Conversão de Angiotensina 2 , Produtos Biológicos , COVID-19 , Schizophyllum , Serina Endopeptidases , Humanos , Adenosina , Enzima de Conversão de Angiotensina 2/genética , SARS-CoV-2/metabolismo , Schizophyllum/química , Serina Endopeptidases/genética , Produtos Biológicos/farmacologia
3.
Angew Chem Int Ed Engl ; 60(5): 2355-2363, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33089963

RESUMO

The regio- and enantioselective (3+3) cycloaddition of nitrones with 2-indolylmethanols was accomplished by the cooperative catalysis of hexafluoroisopropanol (HFIP) and chiral phosphoric acid (CPA). Using this approach, a series of indole-fused six-membered heterocycles were synthesized in high yields (up to 98 %), with excellent enantioselectivities (up to 96 % ee) and exclusive regiospecificity. This approach enabled not only the first organocatalytic asymmetric (3+3) cycloaddition of nitrones but also the first C3-nucleophilic asymmetric (3+3) cycloaddition of 2-indolylmethanols. More importantly, theoretical calculations elucidated the role of the cocatalyst HFIP in helping CPA control the reactivity and enantioselectivity of the reaction, demonstrating a new mode of cooperative catalysis.

4.
Plast Reconstr Surg Glob Open ; 8(8): e3033, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32983788

RESUMO

The fingertip is one of the most common sites of traumatic injuries faced by hand surgeons. In cases of lateral oblique amputation, only limited alternatives are available for reconstruction. This study introduced a new method involving rotation and use of an advancement pulp flap for covering lateral oblique defect and evaluated its outcome. METHOD: A series of 12 patients with 14 lateral oblique fingertip defects were recruited in this study. All fingertips were unreplantable and were injured distal to the proximal one-third of nail bed, with phalanx exposed. All cases received surgical reconstruction using a triangular rotation and advancement pulp flap. Static 2-point discrimination, cold intolerance, pain, hypersensitivity, range of motion, and aesthetic satisfaction were evaluated 6 months to 12 months postoperation. RESULT: Bone defect was noted in 7 cases. The area of defect was 10×7-20×12 mm2, and the angle of defect was 30-60 degrees. Mean follow-up was 14.3 months. No hook nail deformity, cold intolerance, and hypersensitivity were observed. One patient complained about pain postoperation, demanding a second operation. Static 2-point discrimination was between 5 and 8 mm in all cases. Range of motion of distal interphalangeal joint recovered to 20-45 degrees at the last follow-up. No stiffness was observed in the interphalangeal or metacarpophalangeal joints. All patients were satisfied with the appearance of the flap. CONCLUSION: The triangular rotation and advancement pulp flap is simple, safe, and reliable for treating lateral oblique defect of fingertip, providing scope for anatomical reconstruction and fair sensation and aesthetic recovery.

5.
BMC Bioinformatics ; 20(Suppl 8): 289, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182017

RESUMO

BACKGROUND: Gene selection is one of the critical steps in the course of the classification of microarray data. Since particle swarm optimization has no complicated evolutionary operators and fewer parameters need to be adjusted, it has been used increasingly as an effective technique for gene selection. Since particle swarm optimization is apt to converge to local minima which lead to premature convergence, some particle swarm optimization based gene selection methods may select non-optimal genes with high probability. To select predictive genes with low redundancy as well as not filtering out key genes is still a challenge. RESULTS: To obtain predictive genes with lower redundancy as well as overcome the deficiencies of traditional particle swarm optimization based gene selection methods, a hybrid gene selection method based on gene scoring strategy and improved particle swarm optimization is proposed in this paper. To select the genes highly related to out samples' classes, a gene scoring strategy based on randomization and extreme learning machine is proposed to filter much irrelevant genes. With the third-level gene pool established by multiple filter strategy, an improved particle swarm optimization is proposed to perform gene selection. In the improved particle swarm optimization, to decrease the likelihood of the premature of the swarm the Metropolis criterion of simulated annealing algorithm is introduced to update the particles, and the half of the swarm are reinitialized when the swarm is trapped into local minima. CONCLUSIONS: Combining the gene scoring strategy with the improved particle swarm optimization, the new method could select functional gene subsets which are significantly sensitive to the samples' classes. With the few discriminative genes selected by the proposed method, extreme learning machine and support vector machine classifiers achieve much high prediction accuracy on several public microarray data, which in turn verifies the efficiency and effectiveness of the proposed gene selection method.


Assuntos
Algoritmos , Genes , Bases de Dados Genéticas , Humanos , Aprendizado de Máquina , Neoplasias/genética
6.
Chin J Integr Med ; 25(7): 490-496, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29761313

RESUMO

OBJECTIVE: To examine the clinical effects of Yisui Shengxue Granules () in the treatment of ß-thalassemia and explore its mechanism on DNA methylation levels. METHODS: A randomized placebo-controlled double-blinded trial was conducted. Forty patients with ß-thalassemia were recruited and distributed randomly by envelope method into an experimental group and a control group, 20 patients in each group. The patients were given Yisui Shengxue Granules in the experimental group and placebo in the control group (12 g/bag three times a day) during a 3-month intervention. Before and after 1, 2, and 3 months of treatment, peripheral intravenous blood was sampled, and blood parameters such as hemoglobin (Hb), red blood cells (RBCs), reticulocytes (Ret), and fetal hemoglobin (HbF) were analyzed. Mononuclear cells from 5 patients, who showed an obvious treatment effect, were isolated by density gradient centrifugation. DNA methylation was analyzed using an Affymetrix USA GeneChip Human Promoter 1.0 Array and Input-promoter 1.0. RESULTS: Compared with pre-treatment, there was an obvious increase in Hb and RBCs counts after 1, 2, and 3 months in the experiment group (P<0.01 or P<0.05). Meanwhile, HbF increased from the 2nd to the 3rd month (P<0.05). In the control group, Hb and RBCs showed no obvioas change. After 3-month treatment, DNA methylation results from 5 patients revealed that there were 24 hypomethylated genes and 3,685 hypermethylated genes compared with pre-treatment. Genes of insulin-like growth factor 1 receptor (IGF1R) and Janus kinase 3 (JAK3) revealed the most relations with other genes (degree: 21) and genes of 1-phosphatidylinositol-4, 5-bisphosphate phosphodiesterase gamma 2 (PLCG2) and mitogen-activated protein kinase 10 (MAPK10) showed a stronger intermediary role (betweenness centrality=0.04). CONCLUSIONS: JAK3 and MAPK10 are two key genes in bone marrow and the lymphatic system, and JAK3 is likely to be related to hematopoietic cytokines in the process of early hematopoiesis. (Registration No. NCT01549080).


Assuntos
Metilação de DNA/genética , Medicamentos de Ervas Chinesas/uso terapêutico , Talassemia beta/tratamento farmacológico , Talassemia beta/genética , Adolescente , Medicamentos de Ervas Chinesas/farmacologia , Eritrócitos/efeitos dos fármacos , Feminino , Genoma Humano , Hemoglobinas/metabolismo , Humanos , Masculino , Transdução de Sinais
7.
Int J Mol Med ; 42(6): 3193-3208, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30320368

RESUMO

Candida albicans (C. albicans) CDC4 (CaCDC4), encoding the F­box protein for the substrate specificity of the Skp1­cullin­F­box E3 ubiquitin ligase complex, suppresses the yeast­to­filament transition in C. albicans. In our previous study, Thr1 was identified as a CaCdc4­associated protein using affinity purification. THR1 encodes a homoserine kinase, which is involved in the threonine biosynthesis pathway. The present study generated a strain with repressible CaCDC4 expression and continuous THR1 expression. Colony and cell morphology analyses, as well as immunoblotting, revealed that the Thr1 protein was detectable under conditions in which the expression of CaCDC4 was repressed and that the filaments resulting from the repressed expression of CaCDC4 were suppressed by the constitutive expression of THR1 in C. albicans. Additionally, by using the CaSAT1­flipper method, the present study produced null mutants of THR1, GCN4, and CaCDC4. The phenotypic consequences were evaluated by growth curves, spotting assays, microscopic analysis, reverse transcription­polymerase chain reaction and XTT­based biofilm formation ability. The results revealed that fewer cells lacking THR1 entered the stationary phase but had no apparent morphological alteration. It was observed that the expression of THR1 was upregulated concurrently with GCN4 during nutrient depletion and that cells lacking GCN4 rescued the lethality of cells in the absence of THR1 in conditions accumulating homoserine in the threonine biosynthesis pathway. Of note, it was found that cells with either CaCDC4 or THR1 loss were sensitive to oxidative stress and osmotic stress, with those with THR1 loss being more sensitive. In addition, it was observed that cells with loss of either CaCDC4 or THR1 exhibited the ability to increase biofilm formation, with those lacking CaCDC4 exhibiting a greater extent of enhancement. It was concluded that CaCDC4 is important in the coordination of morphogenesis, nutrient sensing, and the stress response through THR1 in C. albicans.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Candida albicans/metabolismo , Candida albicans/fisiologia , Proteínas F-Box/metabolismo , Proteínas Fúngicas/metabolismo , Morfogênese/fisiologia , Nutrientes , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Proteínas F-Box/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Morfogênese/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética
8.
Artigo em Inglês | MEDLINE | ID: mdl-26949404

RESUMO

Yisui Shengxue granules, which is a Chinese traditional medicine, can increase hemoglobin, red blood cells, and Ret of thalassemia patients with mild, moderate, and severe anemia and thus relieve clinical anemia symptoms. Studies on mechanism found that Yisui Shengxue granules can increase the proliferation ability of hematopoietic stem cells. Emodin promoted colony forming of hematopoietic stem cells. Yisui Shengxue granules can increase the activity of GSH-PX in bone marrow blood and decreased the severity of inclusion bodies on the cytomembrane of RBCs. YSSXG attenuated anemia symptoms in patients with thalassemia mostly by increasing the proliferation of hematopoietic stem cells and decreasing the hemolysis of RBCs.

9.
Zhong Yao Cai ; 39(1): 117-20, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-30080013

RESUMO

Objective: To optimize the particle size of rhubarb boiling powder, to determine decoction process of rhubarb boiling powder through the comparative study with traditional herbal pieces. Methods: Three kinds of particle size of rhubarb boiling powder were prepared. The content of aloe emodin,rhein, emodin, chrysophanol and emodin monomethyl ether were detected by HPLC,and to determine particle size of rhubarb boiling powder according to the content of total chemical ingredients and dry extract rate in water decoction. The effect of the amount of water and decocting time on decoction of boiling powder and traditional herbal pieces of rhubarb were systematically investigated by using single factor test. Results: Firstly, the content of 2 mm to 0. 18 mm particles in rhubarb boiling powder can not be less than 80%. Total anthraquinone content and dry extract rate had no significant difference in the decoction of boiling powder in the amount of water between 14 ~ 20 times; decocting time had no significant effect on total anthraquinone and dry extract rate; the content of combined anthraquinone decreased significantly, while the decocting time was more than 20 min. The decocting time had great influence on the herbal pieces, with ten times of water,and decocting 5 ~ 50 min each time, the compound content and dry extract rate of boiling powder were 3. 23 ~ 9. 48 times and 1. 61 ~ 3. 44 times than that of traditional herbal pieces, and with the extension of the decocting time, the gap was narrowing. Conclusion: Preparation process of rhubarb boiling powder is simple and suitable for industrial production, boiling powder can save more than half of the amount of traditional herbal pieces with ten times of water, decocting one times, decoction time of 10 ~ 15 min.


Assuntos
Cromatografia Líquida de Alta Pressão , Rheum , Animais , Antraquinonas , Medicamentos de Ervas Chinesas , Emodina , Pós , Ratos , Ratos Sprague-Dawley
10.
Zhong Yao Cai ; 39(3): 598-602, 2016 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-30091355

RESUMO

Objective: To compare the efficiency of extraction of boiling powder and traditional herbal pieces of root and rhizome, flower, leaf and whole plant medicinal materials for providing a reference for the study and clinical application of boiling powder. Methods: 19 kinds of root and rhizome herbs, the 4 kinds of flower medicinal materials, the 2 kinds of leaf medicinal materials and the 2 kinds of whole plant medicinal materials were chosen as the researh object and were crushed into boiling powder. The contents of the active ingredients and dry extract rate in the water decoction were set as the index to compare the extraction efficiency of boiling powder and traditional herbal pieces. Results: Boiling powder was added ten times of water, decocted one time, decoction time was only ten min, the dry extract rate and the concentration of ingredients in the decoction of boiling powder were not less than those in the traditional decoction of herbal pieces( ten times of water, decoction time was 50 min),this difference was mainly caused by the different of texture density and size of the medicinal materials. Conclusion: The boiling powder can not only save time and facilitate the patient, but also save a lot of medicinal materials from the perspective of chemical medicine, which is beneficial to the sustainable development of medicinal material resources.


Assuntos
Medicina Tradicional Chinesa , Rizoma , Medicamentos de Ervas Chinesas , Flores , Folhas de Planta , Plantas Medicinais , Pós
11.
Eur J Med Chem ; 102: 631-8, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26318069

RESUMO

Tyrosyl-tRNA synthetase (TyrRS), an essential enzyme in bacterial protein biosynthesis, is an attractive therapeutic target for finding novel antibacterial agents, and a series of N2-(arylacetyl)glycinanilides has been herein synthesized and identified as TyrRS inhibitors. These efforts yielded several compounds, with IC50 in the low micromolar range against TyrRS from Staphylococcus aureus. Out of the obtained compounds, 3ap is the most active and exhibits excellent activity against both Gram-positive (S. aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacterial strains. In comparison with the parent scaffold 3-arylfuran-2(5H)-one, N2-(arylacetyl)glycinanilide significantly improved the potency against Gram-negative bacterial strains, indicating that this scaffold offers a significant potential for developing new antibacterial drugs.


Assuntos
Acetanilidas/farmacologia , Antibacterianos/síntese química , Antibacterianos/farmacologia , Benzenoacetamidas/farmacologia , Inibidores Enzimáticos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Tirosina-tRNA Ligase/antagonistas & inibidores , Acetanilidas/síntese química , Acetanilidas/química , Antibacterianos/química , Benzenoacetamidas/síntese química , Benzenoacetamidas/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Bactérias Gram-Positivas/enzimologia , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Tirosina-tRNA Ligase/metabolismo
12.
Can J Microbiol ; 61(4): 247-55, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25719926

RESUMO

The CDC4 gene is nonessential in Candida albicans and plays a role in suppressing filamentous growth, in contrast to its homologues, which are involved in the G1-S transition of the cell cycle. While characterizing the function of C. albicans CDC4 (CaCDC4), we found that the loss of CaCDC4 resulted in a reduction in cell flocculation, indicating a possible role for CaCDC4 in biofilm formation. To elucidate the role of CaCDC4 in biofilm formation, Cacdc4 null mutant strains were constructed by using the mini-Ura-blaster method. To create a CaCDC4 rescued strain, the plasmid p6HF-ACT1p-CaCDC4 capable of constitutively expressing CaCDC4 was introduced into the Cacdc4 homozygous null mutant. To determine the biofilm formation ability, an in vitro XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium-5-carboxanilide) reduction assay was used. Compared with the parental auxotrophic strain BWP17, the Cacdc4 homozygous null mutant was able to enhance biofilm formation significantly. This enhancement of biofilm formation in the Cacdc4 homozygous null mutant could be reversed by constitutively expressing CaCDC4. We conclude that CaCDC4 has a role in suppressing biofilm formation in C. albicans.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida albicans/enzimologia , Candida albicans/fisiologia , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Ubiquitina-Proteína Ligases/metabolismo , Candida albicans/genética , Regulação para Baixo , Proteínas Fúngicas/genética , Ubiquitina-Proteína Ligases/genética
13.
Zhong Yao Cai ; 36(9): 1515-8, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24620700

RESUMO

OBJECTIVE: To study preparation technology and establish the quality standard of Jiangtangyin teabag. METHODS: An orthogonal test was adopted in this study. The transter rate of puerarin and the dried extraction rate were used as indices for optimizing the extraction condition. Quality standards of Jiangtangyin teabag were established by TLC and HPLC method. RESULTS: The best extraction technology was as follows: The drugs were extracted for 3 times, the ratio of water to solid was 10, 8 and 8, respectirely, the extracting time was 1.5 h, 1 h and 1 h respectively. The speckles of TLC method were distinct, accurate and sensitive. The calibration curve of puerarin was linear in the range of 0.168 - 0.84 microg, r2 = 0.9997. CONCLUSION: The preparation process is reasonable and feasible. The methods of quality control are scientific and can be used to control the quality of the Teabag.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Hipoglicemiantes/isolamento & purificação , Isoflavonas/análise , Tecnologia Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cornus/química , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/normas , Temperatura Alta , Hipoglicemiantes/química , Hipoglicemiantes/normas , Pueraria/química , Controle de Qualidade , Reprodutibilidade dos Testes , Solubilidade , Solventes/química , Fatores de Tempo
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