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1.
Artículo en Inglés | MEDLINE | ID: mdl-38334269

RESUMEN

A novel Gram-positive strain WQ 127069T that was isolated from the soil of Baima Snow Mountain, a habitat of highly endangered Yunnan snub-nosed monkeys (Rhinopithecus bieti), was subjected to a polyphasic taxonomic study. Phylogenetic analysis based on the 16S rRNA gene sequences showed that the isolate belongs to the genus Paenibacillus, showing 98.4 and 96.08 % sequence similarity to the type strains Paenibacillus periandrae PM10T and Paenibacillus foliorum LMG 31456T, respectively. The G+C content of the genomic DNA of strain WQ127069T was 45.6 mol%. The predominant isoprenoid quinone was MK-7, and meso-diaminopimelic acid was present in peptidoglycan. The major cellular fatty acids were antiiso-C15 : 0, iso-C15 : 0 and C16 : 0. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylmonomethylethanolamine. The whole genome average nucleotide identity and digital DNA-DNA hybridization values between strain WQ 127069T and strain PM10T were 93.2 and 52.5 %, respectively. Growth occurred at 5-40 °C (optimally at 20-35 °C), pH 6-8 (optimally at pH7.0) and with 0.5-2 % (w/v) NaCl (optimally at 0.5 %). On the basis of the taxonomic evidence, a novel species, Paenibacillus baimaensis sp. nov., is proposed. The type strain is WQ 127069T (=KCTC 43480T=CCTCC AB 2022381T).


Asunto(s)
Paenibacillus , Presbytini , Animales , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Suelo , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , China , Ecosistema
2.
Clin Cancer Res ; 28(24): 5290-5296, 2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36228149

RESUMEN

PURPOSE: The treatment outcome for locally advanced or metastatic soft-tissue sarcoma (STS) remains unsatisfactory. Anlotinib had demonstrated impressive activity in the subsequent-line treatment of STS. This study investigated the combination of anlotinib and epirubicin followed by anlotinib maintenance as first-line treatment for patients with advanced STS. PATIENTS AND METHODS: This prospective, open-label, single-arm, phase II trial was conducted in Zhongshan Hospital, Fudan University. Eligible patients were ages 18 years or older and had previously untreated, pathologically confirmed, unresectable locally advanced or metastatic STS. All patients received up to six cycles of anlotinib plus epirubicin followed by anlotinib maintenance until disease progression, unacceptable toxicity, or death. The primary endpoint was the progression-free survival (PFS) rate at 6 months. The study was registered on chictr.org (identifier ChiCTR1900024928). RESULTS: From June 2019 to August 2020, 30 patients were enrolled. By December 2021, the median PFS was 11.5 months [95% confidence interval (CI): 8.6-14.4 months], while the median overall survival was not reached (95% CI: NE-NE). The objective response rate was 13.33% and the disease control rate was 80.0%. The most common adverse events (AE) included anemia (43.3%), nausea/vomiting (40.0%), fatigue (36.7%), leukopenia (30.0%), and proteinuria (10.0%), which were mainly of grade 1 or 2. The most frequent grade 3 or 4 AEs were anemia (10.0%), febrile neutropenia (33.3%), hypothyroidism (3.3%), and leukopenia (3.3%). No treatment-related death occurred. CONCLUSIONS: The combination of anlotinib and epirubicin followed by anlotinib maintenance demonstrated promising efficacy with a favorable safety profile.


Asunto(s)
Anemia , Leucopenia , Quinolinas , Sarcoma , Neoplasias de los Tejidos Blandos , Humanos , Adolescente , Epirrubicina/efectos adversos , Estudios Prospectivos , Neoplasias de los Tejidos Blandos/patología , Sarcoma/tratamiento farmacológico , Sarcoma/patología , Quinolinas/efectos adversos , Anemia/inducido químicamente , Leucopenia/inducido químicamente
3.
Curr Microbiol ; 79(3): 92, 2022 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-35129696

RESUMEN

A novel bacterium designated WQ 366 T was isolated from the faeces of Bos taurus, foraging on the slopes of the Baima Snow Mountain in Yunnan, China. The isolate grew optimally at 30 â„ƒ and pH 7.0-8.0 without NaCl. The cells were Gram-stain-negative, aerobic, rod-shaped, non-gliding, catalase-positive, and produced yellow color colonies on Columbia Agar. A polyphasic study was applied to clarify its taxonomic position through 16S rRNA gene and genome sequence analysis, and other extensive biological typing. Phylogenetic analysis revealed that the isolate was affiliated to the genus Sphingobacterium and its 16S rRNA gene sequence was closely related to Sphingobacterium bovisgrunnientis YK2 T (97.3%), Sphingobacterium composti T5-12 T (96.4%), and Sphingobacterium cavernae 5.0403-2 T (96.4%). The calculated whole genome average nucleotide identity (ANI) and the digital DNA-DNA hybridization values between strain WQ 366 T and the three related strains were 78.3, 78.6, 73.9 and 21.2, 21.2, 21.0%, respectively. The predominant fatty acids (>10%) were iso-C15:0, iso-C17:0 3-OH, Summed Feature 3 (C16:1 ω7c and/or C16:1 ω6c), and Summed feature 9 (iso-C17:1 ω9c and 10-methyl C16:0). The main polar lipids were PE, GPL, GL, and PL. MK-7 was the major menaquinone. The genome size and the G + C content of WQ 366 T was 4.1 Mb and 34.6%, respectively. All these results indicated that strain WQ 366 T represents a novel species of the Sphingobacterium genus. Therefore, the name Sphingobacterium bovistauri sp. nov. is proposed, and the type strain is WQ 366 T (= CCTCC AA 2020029 T = KCTC 82395 T).


Asunto(s)
Sphingobacterium , Animales , Técnicas de Tipificación Bacteriana , Bovinos , China , ADN Bacteriano/genética , Ácidos Grasos , Heces , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Sphingobacterium/genética , Vitamina K 2
4.
Antonie Van Leeuwenhoek ; 115(2): 271-280, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35031912

RESUMEN

A novel Gram-negative strain WQ 585T, isolated from the faeces of mandrills (Mandrillus sphinx) collected at Yunnan Wild Animal Park, Yunnan province, China, was subjected to a polyphasic taxonomic study. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belongs to the genus Advenella, sharing 98.5% and 98.2% sequence similarity with the type strain Advenella alkanexedens LAM0050T and Advenella faeciporci M-07T, respectively. The predominant ubiquinone was Q-8. The major cellular fatty acids (> 10%) were C16:0, C17:0 cyclo and Summed Feature 2. The G + C content of the genomic DNA of strain WQ 585T was 49.0%. The whole genome average nucleotide identity (gANI) values of strain WQ 585T with strain A. alkanexedens LAM0050T and A. faeciporci M-07T were 86.7% and 86.7%, and the digital DNA-DNA hybridization values of strain WQ 585T with strain A. alkanexedens LAM0050T and A. faeciporci M-07T were 64.5% and 62.5%, respectively. Growth occurred at 10-45 °C (optimally at 20-30 °C), pH 6.0-9.0 (optimally at pH 7.0), and 0-5% (w/v) NaCl (optimally at 0.5-2.0%). On the basis of the taxonomic evidence, a novel species, Advenella mandrilli sp. nov., is proposed. The type strain is WQ 585T (= KCTC 82396 T = CCTCC AA 2020028 T).


Asunto(s)
Mandrillus , Animales , Técnicas de Tipificación Bacteriana , China , ADN Bacteriano/genética , Ácidos Grasos/análisis , Heces/química , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
5.
Artículo en Inglés | MEDLINE | ID: mdl-34382925

RESUMEN

A novel Gram-stain-negative strain, WQ 117T, isolated from the faeces of Rhinopithecus bieti collected at Yunnan Snub-nosed Monkey National Park, Yunnan province, PR China, was subjected to a polyphasic taxonomic study. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate represented a member of the genus Faecalibacter, sharing 97.64 % sequence similarity with the type strain Faecalibacter macacae YIM 102668T. The G+C content of the genomic DNA of WQ117T was 30.5 mol%. The predominant isoprenoid quinone was MK-6. The major cellular fatty acids was iso-C15 : 0. The whole genome average nucleotide identity (gANI) values and the digital DNA-DNA hybridization values between WQ 117T and YIM 102668T were 79.66 % and 22.20 %, respectively. Growth occurred at 0-50 °C (optimally at 28-35 °C), pH 7.0-9.0 (optimally at pH 8.0) and with 0-2 % (w/v) NaCl (optimally without NaCl). On the basis of the taxonomic evidence, a novel species, Faecalibacter rhinopitheci sp. nov., is proposed. The type strain is WQ 117T (=KCTC 82394T=CCTCC AA 2020027T).


Asunto(s)
Bacteroidetes/clasificación , Filogenia , Presbytini , Animales , Técnicas de Tipificación Bacteriana , Bacteroidetes/aislamiento & purificación , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Heces/microbiología , Hibridación de Ácido Nucleico , Presbytini/microbiología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
6.
Arch Microbiol ; 203(7): 4629-4634, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34165622

RESUMEN

A novel bacterium, WQ 047T, was isolated from the faeces of Rhinopithecus bieti, a highly endangered primate endemic to China. The cells were aerobic, oval/rod-shaped, Gram-stain-negative, non-motile, catalase positive, and produced yellow pigmented colonies on Columbia Agar. The taxonomic position of WQ 047T was clarified by applying a polyphasic study based on 16S rRNA gene sequence phylogenetic analysis, extensive biological typing, and whole genome sequencing. Phylogenetic analysis indicated that stain WQ 047T belonged to the genus Sphingobacterium and its 16S rRNA gene sequence exhibited 96.47% pairwise similarity with that of the closest relatives Sphingobacterium nematocida M-SX103T. The calculated whole genome average nucleotide identity (ANI) value between strain WQ 047T and strain M-SX103 was 72.3%. The digital DNA-DNA hybridization value of strain WQ 047T and M-SX103T was 15.73%, which was obtained by calculating the genome-to-genome distance. The major fatty acids were C15:0 iso, C17:0 iso 3-OH, Summed Feature 3 (C16:1 ω7c/C16:1 ω6c) and Summed feature 9 (iso-C17:1ω9c and/or 10-methyl C16:0). The predominant polar lipids were PE, PL and APL. MK-7 was the predominant menaquinone. The G + C content of WQ 047T was 34.89 mol% according to genome analysis. All these characteristics were consistent with those of the genus of Sphingobacterium. Therefore, based on these results, we propose a novel species for which the name Sphingobacterium rhinopitheci sp. Nov. is proposed, with the type strain WQ 047T (= CCTCC AA 2020026T = KCTC82393T).


Asunto(s)
Presbytini , Sphingobacterium , Animales , China , Ácidos Grasos/análisis , Heces/microbiología , Filogenia , Presbytini/microbiología , ARN Ribosómico 16S/genética , Especificidad de la Especie , Sphingobacterium/clasificación , Sphingobacterium/genética
7.
AMB Express ; 10(1): 65, 2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32266507

RESUMEN

The development of novel methods for highly efficient protein purification remains a research focus in the biotechnology field because conventional purification approaches, including affinity purification, gel filtration, and ion-exchange chromatography, require complex manipulation steps and are costly. Here, we describe a simple and rapid protein purification strategy in which the SUMO tag and Ulp1 protease are surface-displayed separately on Escherichia coli cells. After protein induction, the cells are harvested, resuspended in cleavage buffer, and incubated together for cleavage. In this approach, the surface-displayed Ulp1 cleaves the membrane-anchored SUMO fusion protein, resulting in the release of the target protein from the C-terminal of SUMO into the solution. The bacterial cells harboring SUMO and Ulp1 on their surfaces can be easily removed by centrifugation. To evaluate the purification method, we used red fluorescent protein (mCherry). Purified mCherry protein (7.72 ± 1.05 mg from 1 L of bacterial culture) was obtained after only 30 min of incubation. The protein purity was higher than 80%, and could be further improved (> 90%) by simple ultrafiltration. This study offers a promising and simple strategy for the purification of recombinant protein in its native form that requires only cleavage and centrifugation steps.

8.
RSC Adv ; 10(60): 36495-36503, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35517928

RESUMEN

Baby mustard is a perishable vegetable, and thus its distribution and sale as fresh produce face several challenges. However, little effort has been made to identify optimal techniques for postharvest storage of baby mustard. Here, we evaluated the sensory quality, health-promoting compounds, and antioxidant capacity of baby mustard during postharvest storage for 6 days at low temperature (4 °C, LT) and ambient temperature (20 °C). The results showed that visual quality scores, weight, firmness, the contents of most glucosinolates, and the ferric reducing antioxidant power value decreased in the lateral buds of baby mustard during both treatments; however, LT treatment delayed declines in these characteristics. In addition, the contents of glucose, fructose, total soluble sugars, ascorbic acid, and flavonoids, as well as the level of 2,2-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid), decreased considerably throughout the storage period, sucrose content increased throughout the storage period, and the contents of proanthocyanidin and total phenolics first increased and then decreased at 20 °C; however, their contents remained stable throughout the storage period under the LT treatment. These findings indicate that LT provides a promising approach for maintaining the sensory and nutritional quality of baby mustard.

9.
Zhongguo Zhong Yao Za Zhi ; 40(4): 607-13, 2015 Feb.
Artículo en Chino | MEDLINE | ID: mdl-26137677

RESUMEN

In this study, the growth and accumulation of active components of Salvia miltiorrhiza in twenty two experimental sites which crossing through three typical climate zones. The S. miltiorrhiza seedlings with the same genotype were planted in each site in spring, which were cultivated in fields with uniform management during their growing seasons till to harvest. The diterpene ketones (dihydrotanshinone, cryptotanshinone, tanshinone I and tanshinone II(A)) in S. miltiorrhiza root samples were determined by using high-performance liquid chromatography (HPLC) method. The biomass of root (root length, number of root branches, root width and dry weight) was also measured. The results showed that tanshinone II(A) in all samples of each site were higher than the standards required by China Pharmacopoeia. It has been found there is a relationship between root shape and climate change. The correlation analysis between active components and meteorological factors showed that the accumulation of tanshinones were effected by such meteorological factors as average relative humidity from April to October > average vapor pressure from April to October > average temperature difference day and night from April to October > annual average temperature and so on. The correlation analysis between root biomass and meteorological factors exhibited that root shape and accumulation of dry matter were affected by those factors, such as average annual aboveground (0-20 cm) temperature from April to October > annual average temperature > average vapor pressure from April to October > annual active accumulated temperature > annual average temperature > average vapor pressure from April to October. The accumulation of tanshinones and biomass was increased with the decrease of latitude. At the same time, the dry matter and diameter of root decreased if altitude rises. In addition, S. miltiorrhiza required sunlight is not sophisticated, when compared with humid and temperature. To sum up, S. miltiorrhiza can adapt to a variety of climatic conditions and the southern warm humid climate is more conducive to its growth and accumulation of active components.


Asunto(s)
Medicamentos Herbarios Chinos/análisis , Raíces de Plantas/crecimiento & desarrollo , Salvia miltiorrhiza/química , Biomasa , China , Cambio Climático , Ecosistema , Raíces de Plantas/química , Salvia miltiorrhiza/crecimiento & desarrollo , Temperatura
10.
J BUON ; 20(2): 631-44, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26011360

RESUMEN

PURPOSE: The role of let-7 family members in cancer prognosis has been the subject of increasing interest; however, the correlation between let-7 expression and cancer prognosis remains unknown. The goal of this study was to investigate the prognostic role of let-7 expression by performing a meta-analysis update of 31 studies. METHODS: All relevant studies were searched on PubMed and Web of Science. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated, and subgroup analysis was performed for overall survival (OS) and disease-free survival (DFS) to evaluate the relationship between high let-7 expression and cancer prognosis. Heterogeneity and publication bias were also investigated. RESULTS: We discovered that high let-7 expression can predict a better OS (pooled HR=0.69, 95% CI 0.60-0.80, transformed from lnHR and its 95% CI) and DFS (pooled HR=0.72, 95% CI 0.54-0.96, transformed from lnHR and its 95% CI) in various carcinomas, especially in digestive cancer. Subgroup analysis showed that high let-7 expression was significantly associated with a better DFS in Asians (pooled HR=0.50, 95% CI 0.39-0.64, transformed from lnHR and its 95% CI). CONCLUSIONS: This meta-analysis showed that high let-7 expression is a prognostic factor for better OS and DFS in cancer patients, with particularly better DFS among the Asian populations. These results suggest that clinicians should treat patients with low let-7 expression more carefully. Future studies in large-scale populations among different ethnicities and regions are needed to definitively determine if let-7 expression can be used as a predicative biomarker for clinical assessment.


Asunto(s)
MicroARNs/fisiología , Neoplasias/genética , Supervivencia sin Enfermedad , Humanos , Neoplasias/mortalidad , Pronóstico , Sesgo de Publicación
11.
J Agric Food Chem ; 60(24): 6150-6, 2012 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-22640226

RESUMEN

Terpinen-4-ol, an active component of tea tree oil, exhibits broad-spectrum antimicrobial activity. However, the high volatilization of terpinen-4-ol and its nonwettability property have limited its application. Our objective was to synthesize novel nanocarriers to deliver and protect terpinen-4-ol. The polyethylene glycol (PEG)-stabilized lipid nanoparticles were prepared and characterized by scanning electron microscope, Zetasizer, and differential scanning calorimetry. These nanoparticles had an average diameter of 397 nm and a Ζ-potential of 10 mV after being modified by glycine. Results showed that homogeneous particle size, high drug loading, stability, and targeting were obtained by the nanoparticles. Liquid chromatography/mass spectrometry showed a sustained release trend from nanoparticles for terpinen-4-ol. Minimum inhibitory concentration and minimum biofilm eradication concentration were tested against Candida albicans ATCC 11231. Studies on isolated mitochondria showed the blockage of biofilm respiration and inhibition of enzyme activity. The effects can be ascribed to localization of terpinen-4-ol on the membrane of mitochondria.


Asunto(s)
Antiinfecciosos/administración & dosificación , Biopelículas/efectos de los fármacos , Nanopartículas/química , Polietilenglicoles/química , Terpenos/administración & dosificación , Candida albicans/efectos de los fármacos , Candida albicans/fisiología , Preparaciones de Acción Retardada , Estabilidad de Medicamentos , Lípidos/química , Tamaño de la Partícula , Aceite de Árbol de Té/química , Volatilización
12.
Food Chem ; 132(1): 419-27, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-26434310

RESUMEN

Chitosan was combined with nano-ZnO to increase its antimicrobial activity, using polyvinyl alcohol as a support, and then were electronspun to form composite nanofibres. Through SEM, EDX and XRD observations, chitosan was seen to be able to incorporate nano-ZnO in the composite nanofibres. Escherichia coli, expressing recombinant enhanced green fluorescent protein, and Candida albicans were used to test the antimicrobial efficacy of the newly synthesised chitosan/nano-ZnO antimicrobial composite. The CdTe quantum dots were used to rapidly detect the residual changes of C. albicans and determine the end point of using antimicrobial agents. Minimal minimum inhibitory concentration (MIC), post-antibiotic effect and continuous agent effect of the composite were determined. The MIC of chitosan/nano-ZnO against C. albicans was 160µg/ml, close to the concentration of the treated composite with the lowest fluorescence intensity. The cell damage was observed by SEM, which indicated that nano-ZnO in the nanofibrous membranes played a cooperative role in the antimicrobial process of chitosan.


Asunto(s)
Antibacterianos/administración & dosificación , Antiinfecciosos/administración & dosificación , Quitosano/administración & dosificación , Nanopartículas del Metal , Óxido de Zinc/administración & dosificación , Candida albicans/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Expresión Génica , Proteínas Fluorescentes Verdes/genética , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo
13.
Int J Nanomedicine ; 6: 667-76, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21556341

RESUMEN

PURPOSE: The objective of the present investigation was to evaluate the antibacterial properties and the biocompatibility of composite electrospun nanofibrous membranes (NFMs) with low-molecular-weight fish scale collagen peptides (FSCP) and chito-oligosaccharide (COS), to determine their potential for use as wound dressings. METHODS: Low-molecular-weight FSCP were combined with COS to prepare nanofibers by electrospinning, and polyvinyl alcohol (PVA) was used for enhancing fiber-forming ability. Transmission electron microscope and scanning electron microscope methods were used to observe bacterial adhesion and the bacterial cell membrane. Fibroblast cell viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. RESULTS: The best FSCP/COS mass ratio for electrospinning was 2:1, and the nanofibers had small dimensions ranging from 50 to 100 nm. The NFM showed good antibacterial activities against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. The antibacterial activity against S. aureus was higher than against E. coli. The pili and adhesive fimbriae of E. coli promoted bacterial adhesion to the NFM surfaces, and S. aureus biofilms aided S. aureus adhesion on the surface of NFMs. Damage to the bacterial cell membrane indicates that the NFMs could lead to the release of intracellular materials, particularly with S. aureus. In addition, FSCP/COS NFM rapidly increased the permeability of the outer membranes of E. coli. The electrospun NFM with FSCP and COS had good biocompatibility in vitro and supported proliferation of human skin fibroblasts. CONCLUSION: FSCP are superior to mammalian collagen, and have feasibility and potency for wound dressings. FSCP/COS NFMs had good anti-bactericidal activity that improved with increased COS, and showed good biocompatibility in vitro and supported the proliferation of fibroblasts.


Asunto(s)
Antibacterianos/farmacología , Colágeno/farmacología , Proteínas de Peces/farmacología , Membranas Artificiales , Nanoestructuras/química , Animales , Antibacterianos/química , Vendajes , Adhesión Celular/efectos de los fármacos , Adhesión Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Quitina/química , Quitina/farmacología , Colágeno/química , Técnicas Electroquímicas , Escherichia coli/efectos de los fármacos , Fibroblastos , Proteínas de Peces/química , Humanos , Microscopía Electrónica de Rastreo , Oligosacáridos/química , Oligosacáridos/farmacología , Péptidos/química , Péptidos/farmacología , Staphylococcus aureus/efectos de los fármacos
14.
J Agric Food Chem ; 59(9): 5087-92, 2011 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-21417240

RESUMEN

(-)-Epigallocatechin-3-gallate (EGCG) exhibited strong antimicrobial activity. However, the easy oxidation of EGCG has limited its application. To increase the antimicrobial activity and stability of EGCG, the EGCG-Cu(II) complex was formed by chelating copper ions and then electronspun into polyvinyl alcohol (PVA) nanofibers. Electronspun nanofibrous membranes were investigated by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM), which showed that the average fiber diameter was 210 nm. Minimal inhibitory concentrations (MICs) of EGCG-Cu(II)/PVA membranes were tested against the tested strains. The bactericidal activity of EGCG-Cu(II) was suppressed by ethylenediaminetetraacetic acid (EDTA). Cell killing was accompanied by the leakage of intracellular proteins, indicating that the cytoplasmic membrane was badly damaged after exposure to the EGCG-Cu(II)/PVA membrane. We observed the process of cell damage by SEM. On the basis of experimental evidence and theoretical analyses, the mechanism proposed that copper ions played a cooperative role in the bactericidal process of EGCG. To evaluate the antimicrobial activity of the EGCG-Cu(II)/PVA membrane, we developed a rapid detection method by labeling cells with water-soluble CdTe quantum dots.


Asunto(s)
Antiinfecciosos/química , Catequina/análogos & derivados , Cobre/química , Nanoestructuras/química , Alcohol Polivinílico/química , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Catequina/química , Catequina/farmacología , Cobre/farmacología , Sistemas de Liberación de Medicamentos/instrumentación , Estabilidad de Medicamentos , Hongos/efectos de los fármacos , Membranas Artificiales , Viabilidad Microbiana/efectos de los fármacos , Alcohol Polivinílico/farmacología
15.
Org Biomol Chem ; 8(10): 2320-2, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-20376384

RESUMEN

A series of new chiral phosphine-phosphoramidite ligands with a 3,3'-substituted binaphthyl moiety were prepared from 1-phenylethylamine, and successfully applied in the Rh-catalyzed asymmetric hydrogenation of beta-(acylamino)-acrylates. The research disclosed that the substituents on the 3,3'-positions of binaphthyl moiety significantly influenced the enantioselectivity.


Asunto(s)
Acrilatos/química , Naftalenos/química , Compuestos Organofosforados/química , Fenetilaminas/química , Fosfinas/química , Rodio/química , Catálisis , Hidrogenación , Ligandos , Estereoisomerismo , Especificidad por Sustrato
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