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111.
Y. P. Cruz R. S. Treichel E. Harsay K. D. Chi 《In vitro cellular & developmental biology. Animal》1993,29(8):671-675
Summary Immunosurgery is a useful technique for the isolation of inner cell masses from murine blastocysts. Conventionally, rabbit
antisera made ad hoc against murine splenic or fetal cells or fibroblasts have been used as antibody sources. We investigated
the feasibility of using commercially available rabbit antiserum to murine erythrocytes (anti-RBC) and compared it with rabbit
antiserum generated ad hoc to murine L-cells (anti-L-cell). Our results indicate that anti-RBC is at least as effective as
anti-L-cell serum for the immunosurgical isolation of inner cell masses, which became either miniblastocysts (later forming
outgrowths) or embryoid bodies (undergoing ectoderm-endodermlike differentiation within 48 h). Because anti-RBC is commercially
available, the technical modification described herein increases the accessibility of the immunosurgical protocol for the
isolation of murine inner cell masses. 相似文献
112.
Chunping Ma Jiyin He Yancheng Wu Junlang Li Jiayi Chen Yangfan Zhang Jinpeng Mo Haibo Xie Zhenguo Chi Yang Li Yongcan Jin 《Luminescence》2023,38(10):1720-1728
Multistimuli-responsive fluorescent materials have garnered great research interest benefited from their practical applications. Two twisted-structure compounds containing tetraphenylethylene (TPE) as the aggregation-induced emission (AIE) group and a pyridine unit as the acid reaction site to obtain new multistimuli-responsive fluorescent compounds (namely, TPECNPy: TPECNPy-2 and TPECNPy-3) were successfully synthesized through a one-step Knoevenagel condensation reaction. The multiple-stimuli response process of TPECNPy was investigated by means of photoluminescence (PL) spectra and emission colour. The results showed that both TPECNPy compounds with excellent AIE abilities displayed reversible emission wavelength and colour changes in response to multiple external stimuli, including grinding–fuming by CH2Cl2 or annealing and HCl-NH3 vapour fuming. More importantly, fluorescent nanofibre films were prepared by electrospinning a solution of TPECNPy mixed with cellulose acetate (CA), and these exhibited reversible acid-induced discolouration, even with only 1 wt% TPECNPy. The results of this study may inspire strategies for designing multistimuli-responsive materials and preparing fluorescent sensing nanofibre films. 相似文献
113.
114.
T Nguyen P Sambrook P Kelly G Jones S Lord J Freund J Eisman 《BMJ (Clinical research ed.)》1993,307(6912):1111-1115
OBJECTIVE--To investigate the utility of risk factors such as bone mineral density, lifestyle, and postural stability in the prediction of osteoporotic fractures. DESIGN--Longitudinal, epidemiological, and population based survey. SETTING--City of Dubbo, New South Wales. SUBJECTS--All residents of Dubbo aged > or = 60 on 1 January 1989. MAIN OUTCOME MEASURE--Incidence of fracture for individual subjects. RESULTS--The overall incidence of atraumatic fractures in men and women was 1.9% and 3.1% per annum respectively. The predominant sites of fracture were hip (18.9%), distal radius (18.5%), ribs and humerus (11.9% in each case), and ankle and foot (9.1% and 6.6% respectively). Major predictors of fractures in men and women were femoral neck bone mineral density, body sway, and quadriceps strength. Age, years since menopause, height, weight, and lifestyle factors were also correlated with bone mineral density and body sway and hence were indirect risk factors for fracture. Discriminant function analysis correctly identified 96% and 93% (sensitivities 88% and 81%) of men and women, respectively, who subsequently developed atraumatic fractures. Predictions based on this model indicated that a woman with a bone mineral density in the lowest quartile in the hip together with high body sway had a 8.4% probability of fracture per annum. This represented an almost 14-fold increase in risk of fracture compared with a woman in the highest bone mineral density quartile with low postural sway. An individual with all three predictors in the "highest risk" quartile had a 13.1% risk of fracture per annum. CONCLUSIONS--Bone mineral density, body sway, and muscle strength are independent and powerful synergistic predictors of fracture incidence. 相似文献
115.
Xuan Cuong Mai Chia-Rui Shen Chao-Lin Liu Dang Mau Trinh Minh Ly Nguyen 《Journal of phycology》2023,59(4):775-784
Species identification of Scenedesmus-like microalgae, comprising Desmodesmus, Tetradesmus, and Scenedesmus, has been challenging due to their high morphological and genetic similarity. After developing a DNA signaturing tool for Desmodesmus identification, we built a DNA signaturing database for Tetradesmus. The DNA signaturing tool contained species-specific nucleotide sequences of Tetradesmus species or strain groups with high similarity in ITS2 sequences. To construct DNA signaturing, we collected data on ITS2 sequences, aligned the sequences, organized the data by ITS2 sequence homology, and determined signature sequences according to hemi-compensatory base changes (hCBC)/CBC data from previous studies. Four Tetradesmus species and 11 strain groups had DNA signatures. The signature sequence of the genus Tetradesmus, TTA GAG GCT TAA GCA AGG ACCC, recognized 86% (157/183) of the collected Tetradesmus strains. Phylogenetic analysis of Scenedesmus-like species revealed that the Tetradesmus species were monophyletic and closely related to each other based on branch lengths. Desmodesmus was suggested to split into two subgenera due to their genetic and morphological distinction. Scenedesmus must be analyzed along with other genera of the Scenedesmaceae family to determine their genetic relationships. Importantly, DNA signaturing was integrated into a database for identifying Scenedesmus-like species through BLAST. 相似文献
116.
Single crystals were grown from affinity-purified stinging nettle lectin and from its complex with the specific trisaccharide NN′N″ -triacetylchitotriose by vapor diffusion at room temperature. The lectin crystallizes in space group P212121 with unit cell dimensions a = 54.3 (1) Å, b = 62.2 (1) Å, and c = 92.4 (2) Å, and diffracts to 3.0 Å resolution. The asymmetric unit contains three lectin monomers. The crystals of the lectin-trisaccharide complex have space group P212121 with cell constants a = 37.69 (4) Å, b = 48.97 (6) Å, and c = 57.32 (4) Å. These crystals diffract to at least 2.0 Å resolution and the asymmetric unit contains one lectin monomer. A three-dimensional X-ray structure determination is on its way. © 1993 Wiley-Liss, Inc. 相似文献
117.
Thi-Lan-Phuong Nguyen Catherine Béal Sarrah Ghorbal Claire Saulou-Bérion 《Biotechnology progress》2023,39(1):e3299
3-Hydroxypropionic acid (3-HP) is a platform molecule whose biological production was carried out by the bacterium Limosilactobacillus reuteri according to a two-step process: first, a growth phase in batch mode on glucose, then a glycerol bioconversion into 3-HP in fed-batch mode. With the objective of improving 3-HP bioproduction, this study aimed at defining the operating conditions during the bioconversion phase that increases the bioproduction performance. A central composite rotatable design allowed testing various pH levels and specific glycerol feeding rates. By establishing response surfaces, optimal conditions have been identified that were different depending on the considered output variable (final 3-HP quantity, 3-HP production yield and production rate). Of them, 3-HP final quantity and 3-HP production yield were maximized at pH 6.0 and at specific glycerol feeding rates of 60 and 55 mggly gCDW−1 h−1, respectively. The specific 3-HP production rate was the highest at the upper limit of the specific substrate feeding rate (80 mggly gCDW−1 h−1) but was not affected by the pH. An additional experiment was carried out at pH 6.0 and a specific glycerol feeding rate of 80 mggly gCDW−1 h−1 to validate the previous observations. In conclusion, the results showed a significant improvement of 3-HP concentration by 13%, of specific production rate by 34% and of 3-HP volumetric productivity by 39%, as compared to the initial values. 相似文献
118.
Bui Hai Ninh Duong Thi Dung Bui Huu Tai Pham Hai Yen Nguyen Xuan Nhiem Truong Thi Thu Hien Do Thi Trang Nguyen Van Tuyen Le Tuan Anh Nguyen Thi Hoai Phan Van Kiem 《化学与生物多样性》2023,20(3):e202201048
A new isopropyl chromone ( 1 ) and a new flavanone glucoside ( 2 ) together with eleven known compounds ( 3–13 ) were isolated from the leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry. Their structures were elucidated as 5,7-dihydroxy-2-isopropyl-6,8-dimethyl-4H-chromen-4-one ( 1 ), 5,7-dihydroxyflavanone 7-O-β-D-(6′′-O-galloylglucopyranoside) ( 2 ), strobopinin ( 3 ), demethoxymatteucinol ( 4 ), pinocembrin-7-O-β-D-glucopyranoside ( 5 ), (2S)-hydroxynaringenin-7-O-β-D-glucopyranoside ( 6 ), afzelin ( 7 ), quercetin ( 8 ), kaplanin ( 9 ), endoperoxide G3 ( 10 ), grasshopper ( 11 ), vomifoliol ( 12 ), litseagermacrane ( 13 ) by the analysis of HR-ESI-MS, NMR, and CD spectral data. Compounds 1 , 2 , 5 , 6 and 10 inhibited NO production on LPS-activated RAW264.7 cells with IC50 values of 12.28±1.15, 8.52±1.62, 7.68±0.87, 9.67±0.57, and 6.69±0.34 μM, respectively, while the IC50 values of the other compounds ranging from 33.38±0.78 to 86.51±2.98 μM, compared to that of the positive control, NG-monomethyl-L-arginine acetate (L-NMMA) with an IC50 value of 32.50±1.00 μM. 相似文献
119.
Nguyen Dinh Luyen Le Mai Huong Nguyen Thi Thu Ha Nguyen Thanh Tra Le Thi Tu Anh Nguyen Van Tuyen Katalin Posta Ninh The Son Hai Pham-The 《化学与生物多样性》2023,20(2):e202200456
The current report describes the chemical investigation and biological activity of extracts produced by three fungal strains Fusarium oxysporum, Penicillium simplicissimum, and Fusarium proliferatum isolated from the roots of Piper nigrum L. growing in Vietnam. These fungi were namely determined by morphological and DNA analyses. GC/MS identification revealed that the EtOAc extracts of these fungi were associated with the presence of saturated and unsaturated fatty acids. These EtOAc extracts showed cytotoxicity towards cancer cell lines HepG2, inhibited various microbacterial organisms, especially fungus Aspergillus niger and yeast Candida albicans (the MIC values of 50–100 μg/mL). In α-glucosidase inhibitory assay, they induced the IC50 values of 1.00-2.53 μg/mL were better than positive control acarbose (169.80 μg/mL). The EtOAc extract of F. oxysporum also showed strong anti-inflammatory activity against NO production and PGE-2 level. Four major compounds linoleic acid (37.346 %), oleic acid (27.520 %), palmitic acid (25.547 %), and stearic acid (7.030 %) from the EtOAc extract of F. oxysporum were selective in molecular docking study, by which linoleic and oleic acids showed higher binding affinity towards α-glucosidase than palmitic and stearic acids. In subsequent docking assay with inducible nitric oxide synthase (iNOS), palmitic acid, oleic acid and linoleic acid could be moderate inhibitors. 相似文献
120.
Nguyen Huy Hung Pham Minh Quan Do Ngoc Dai Prabodh Satyal Le Thi Huong Le Duc Giang Le Thanh Hung William N. Setzer 《化学与生物多样性》2023,20(3):e202200210
There is an ongoing interest to identify alternative pesticidal agents to avoid the chronic problems associated with synthetic pesticides. Essential oils have shown promise as botanical pest control agents. In the present study, the essential oils of four members of the Lamiaceae (Callicarpa candicans, C. erioclona, C. macrophylla, and Karomia fragrans; Vietnamese names: Nàng nàng, Tu châu lông mem, Tu châu lá to and Cà diện, respectively), obtained from wild populations in Vietnam, have been obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The essential oils were formulated into microemulsions and the essential oils and their microemulsions were screened for mosquito larvicidal activity against Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and for molluscicidal activity against Pomacea canaliculata. Atractylone and (E)-caryophyllene dominated the volatiles of C. candicans (CCEO) and C. erioclona (CEEO), while the major component in C. macrophylla (CMEO) and K. fragrans (KFEO) was (E)-caryophyllene. The essential oils and microemulsions of both C. candicans and C. erioclona exhibited excellent larvicidal activity against all three mosquito species (Ae. aegypti, Ae. albopictus, and Cx. quinquefasciatus) with LC50 values <10 μg/mL. Additionally, the larvicidal activity of the microemulsions were significantly improved compared with their free essential oils, especially for C. candicans and C. erioclona. All four essential oils and their microemulsions showed excellent molluscicidal activity with LC50 <10 μg/mL. In most cases, the essential oils and microemulsions showed greater pesticidal activity against target organisms than the non-target freshwater fish, Oreochromis niloticus. The in silico studies on physicochemical and ADMET properties of the major components in the studied essential oils were also investigated and most of the compounds possessed a favorable ADMET profile. Computational modeling studies of the studied compounds demonstrated a favorable binding interaction with the mosquito odorant-binding protein target and support atractylone, β-selinene, and caryophyllene oxide as potential inhibitors. Based on the observed pesticidal activities of the essential oils and their microemulsions, the Callicarpa species and K. fragrans should be considered for potential cultivation and further exploration as botanical pesticidal agents. 相似文献