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1.
Imeta ; 3(3): e185, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38898981

RÉSUMÉ

The vaginal microbiome plays an essential role in the reproductive health of human females. As infertility increases worldwide, understanding the roles that the vaginal microbiome may have in infertility and in vitro fertilization (IVF) treatment outcomes is critical. To determine the vaginal microbiome composition of 1411 individuals (1255 undergoing embryo transplantation) and their associations with reproductive outcomes, clinical and biochemical features are measured, and vaginal samples are 16S rRNA sequenced. Our results suggest that both too high and too low abundance of Lactobacillus is not beneficial for pregnancy; a moderate abundance is more beneficial. A moderate abundance of Lactobacillus crispatus and Lactobacillus iners (~80%) (with a pregnancy rate of I-B: 54.35% and III-B: 57.73%) is found beneficial for pregnancy outcomes compared with a higher abundance (>90%) of Lactobacillus (I-A: 44.81% and III-A: 51.06%, respectively). The community state type (CST) IV-B (contains a high to moderate relative abundance of Gardnerella vaginalis) shows a similar pregnant ratio (48.09%) with I-A and III-A, and the pregnant women in this CST have a higher abundance of Lactobacillus species. Metagenome analysis of 71 samples shows that nonpregnant women are detected with more antibiotic-resistance genes, and Proteobacteria and Firmicutes are the main hosts. The inherent differences within and between women in different infertility groups suggest that vaginal microbes might be used to detect infertility and potentially improve IVF outcomes.

2.
Adv Sci (Weinh) ; 11(24): e2305706, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38582509

RÉSUMÉ

Haplotype-resolved 3D chromatin architecture related to allelic differences in avian skeletal muscle development has not been addressed so far, although chicken husbandry for meat consumption has been prevalent feature of cultures on every continent for more than thousands of years. Here, high-resolution Hi-C diploid maps (1.2-kb maximum resolution) are generated for skeletal muscle tissues in chicken across three developmental stages (embryonic day 15 to day 30 post-hatching). The sequence features governing spatial arrangement of chromosomes and characterize homolog pairing in the nucleus, are identified. Multi-scale characterization of chromatin reorganization between stages from myogenesis in the fetus to myofiber hypertrophy after hatching show concordant changes in transcriptional regulation by relevant signaling pathways. Further interrogation of parent-of-origin-specific chromatin conformation supported that genomic imprinting is absent in birds. This study also reveals promoter-enhancer interaction (PEI) differences between broiler and layer haplotypes in skeletal muscle development-related genes are related to genetic variation between breeds, however, only a minority of breed-specific variations likely contribute to phenotypic divergence in skeletal muscle potentially via allelic PEI rewiring. Beyond defining the haplotype-specific 3D chromatin architecture in chicken, this study provides a rich resource for investigating allelic regulatory divergence among chicken breeds.


Sujet(s)
Poulets , Haplotypes , Muscles squelettiques , Animaux , Poulets/génétique , Haplotypes/génétique , Muscles squelettiques/métabolisme , Cartographie chromosomique/méthodes , Génome/génétique
3.
G3 (Bethesda) ; 14(1)2023 Dec 29.
Article de Anglais | MEDLINE | ID: mdl-37832513

RÉSUMÉ

Ovarian follicle development is a complex and well-orchestrated biological process of great economic significance for poultry production. Specifically, understanding the molecular mechanisms underlying follicular development is essential for high-efficiency follicular development can benefit the entire industry. In addition, domestic egg-laying hens often spontaneously develop ovarian cancer, providing an opportunity to study the genetic, biochemical, and environmental risk factors associated with the development of this cancer. Here, we provide high-quality RNA sequencing data for chicken follicular granulosa cells across 10 developmental stages, which resulted in a total of 204.57 Gb of clean sequencing data (6.82 Gb on average per sample). We also performed gene expression, time-series, and functional enrichment analyses across the 10 developmental stages. Our study revealed that SWF (small while follicle), F1 (F1 hierarchical follicles), and POFs (postovulatory follicles) best represent the transcriptional changes associated with the prehierarchical, preovulatory, and postovulatory stages, respectively. We found that the preovulatory stage F1 showed the greatest divergence in gene expression from the POF stage. Our research lays a foundation for further elucidation of egg-laying performance of chicken and human ovarian disease.


Sujet(s)
Poulets , Follicule ovarique , Femelle , Animaux , Humains , Poulets/génétique , Follicule ovarique/métabolisme , Cellules de la granulosa/composition chimique , Cellules de la granulosa/métabolisme , Séquence nucléotidique , ARN messager/génétique , ARN messager/métabolisme
4.
JAMA ; 329(24): 2135-2144, 2023 06 27.
Article de Anglais | MEDLINE | ID: mdl-37367978

RÉSUMÉ

Importance: Intravenous thrombolysis is increasingly used in patients with minor stroke, but its benefit in patients with minor nondisabling stroke is unknown. Objective: To investigate whether dual antiplatelet therapy (DAPT) is noninferior to intravenous thrombolysis among patients with minor nondisabling acute ischemic stroke. Design, Setting, and Participants: This multicenter, open-label, blinded end point, noninferiority randomized clinical trial included 760 patients with acute minor nondisabling stroke (National Institutes of Health Stroke Scale [NIHSS] score ≤5, with ≤1 point on the NIHSS in several key single-item scores; scale range, 0-42). The trial was conducted at 38 hospitals in China from October 2018 through April 2022. The final follow-up was on July 18, 2022. Interventions: Eligible patients were randomized within 4.5 hours of symptom onset to the DAPT group (n = 393), who received 300 mg of clopidogrel on the first day followed by 75 mg daily for 12 (±2) days, 100 mg of aspirin on the first day followed by 100 mg daily for 12 (±2) days, and guideline-based antiplatelet treatment until 90 days, or the alteplase group (n = 367), who received intravenous alteplase (0.9 mg/kg; maximum dose, 90 mg) followed by guideline-based antiplatelet treatment beginning 24 hours after receipt of alteplase. Main Outcomes and Measures: The primary end point was excellent functional outcome, defined as a modified Rankin Scale score of 0 or 1 (range, 0-6), at 90 days. The noninferiority of DAPT to alteplase was defined on the basis of a lower boundary of the 1-sided 97.5% CI of the risk difference greater than or equal to -4.5% (noninferiority margin) based on a full analysis set, which included all randomized participants with at least 1 efficacy evaluation, regardless of treatment group. The 90-day end points were assessed in a blinded manner. A safety end point was symptomatic intracerebral hemorrhage up to 90 days. Results: Among 760 eligible randomized patients (median [IQR] age, 64 [57-71] years; 223 [31.0%] women; median [IQR] NIHSS score, 2 [1-3]), 719 (94.6%) completed the trial. At 90 days, 93.8% of patients (346/369) in the DAPT group and 91.4% (320/350) in the alteplase group had an excellent functional outcome (risk difference, 2.3% [95% CI, -1.5% to 6.2%]; crude relative risk, 1.38 [95% CI, 0.81-2.32]). The unadjusted lower limit of the 1-sided 97.5% CI was -1.5%, which is larger than the -4.5% noninferiority margin (P for noninferiority <.001). Symptomatic intracerebral hemorrhage at 90 days occurred in 1 of 371 participants (0.3%) in the DAPT group and 3 of 351 (0.9%) in the alteplase group. Conclusions and Relevance: Among patients with minor nondisabling acute ischemic stroke presenting within 4.5 hours of symptom onset, DAPT was noninferior to intravenous alteplase with regard to excellent functional outcome at 90 days. Trial Registration: ClinicalTrials.gov Identifier: NCT03661411.


Sujet(s)
Fibrinolytiques , Accident vasculaire cérébral ischémique , Antiagrégants plaquettaires , Activateur tissulaire du plasminogène , Femelle , Humains , Mâle , Adulte d'âge moyen , Hémorragie cérébrale/induit chimiquement , Fibrinolytiques/administration et posologie , Fibrinolytiques/effets indésirables , Fibrinolytiques/usage thérapeutique , Accident vasculaire cérébral ischémique/traitement médicamenteux , Antiagrégants plaquettaires/administration et posologie , Antiagrégants plaquettaires/effets indésirables , Antiagrégants plaquettaires/usage thérapeutique , Accident vasculaire cérébral/traitement médicamenteux , Activateur tissulaire du plasminogène/effets indésirables , Activateur tissulaire du plasminogène/usage thérapeutique , Résultat thérapeutique , Association de médicaments , Traitement thrombolytique/effets indésirables , Traitement thrombolytique/méthodes , Administration par voie intraveineuse , Clopidogrel/administration et posologie , Clopidogrel/effets indésirables , Clopidogrel/usage thérapeutique , Acide acétylsalicylique/administration et posologie , Acide acétylsalicylique/effets indésirables , Acide acétylsalicylique/usage thérapeutique , Études de suivi , Sujet âgé , Récupération fonctionnelle
5.
Front Microbiol ; 13: 951726, 2022.
Article de Anglais | MEDLINE | ID: mdl-36081790

RÉSUMÉ

Sustainable meat production is important to providing safe and quality protein sources for humans worldwide. Intensive artificial selection and high energy input into the diet of many commercial animals for the last decade has significantly increased the daily gain of body weight and shortened the raising period, but unexpectedly decreased the meat quality. The gastrointestinal tract of animals harbors a diverse and complex microbial community that plays a vital role in the digestion and absorption of nutrients, immune system development, pathogen exclusion, and meat quality. Fatty acid composition and oxidative stress in adipose and muscle tissue influences meat quality in livestock and poultry. Recent studies showed that nutraceuticals are receiving increased attention, which could alter the intestinal microbiota and regulate the fat deposition and immunity of hosts to improve their meat quality. Understanding the microbiota composition, the functions of key bacteria, and the host-microbiota interaction is crucial for the development of knowledge-based strategies to improve both animal meat quality and host health. This paper reviews the microorganisms that affect the meat quality of livestock and poultry. A greater understanding of microbial changes that accompany beneficial dietary changes will lead to novel strategies to improve livestock and poultry meat product quality.

6.
Sci Data ; 9(1): 552, 2022 09 08.
Article de Anglais | MEDLINE | ID: mdl-36075978

RÉSUMÉ

The chicken provides large amounts of protein for the human diet and is also used as a model organism for biomedical research. Increasing meat production is an important goal in the poultry industry and skeletal muscles have highly diverse origins, shapes, metabolic features, and physical functions. Previous gene expression atlases have largely ignored the differences among diverse types of skeletal muscles; therefore, comprehensive transcriptional maps of all skeletal muscles are needed to improve meat production traits. In this study, we sequenced 58 samples from 10 different skeletal muscles of 42-day-old White Plymouth Rock chickens. We also measured myofiber diameter and generated myofiber-type datasets of these 10 tissues. We generated 418.4 Gb high-quality bulk RNA-Seq data from four or six biological replicates of each skeletal muscle (four replicates from extraocular samples) (approximately 7.4 Gb per sample). This dataset provides valuable information for understanding the muscle fiber characteristics of White Plymouth Rock chickens. Furthermore, our data can be used as a model for heterogeneity analysis between tissues with similar properties.


Sujet(s)
Poulets , Transcriptome , Animaux , Poulets/génétique , Viande/analyse , Fibres musculaires squelettiques/métabolisme , Muscles squelettiques/métabolisme
7.
J Anim Sci Biotechnol ; 13(1): 32, 2022 Mar 12.
Article de Anglais | MEDLINE | ID: mdl-35277200

RÉSUMÉ

BACKGROUND: A growing body of evidence has revealed that the mammalian genome is organized into hierarchical layers that are closely correlated with and may even be causally linked with variations in gene expression. Recent studies have characterized chromatin organization in various porcine tissues and cell types and compared them among species and during the early development of pigs. However, how chromatin organization differs among pig breeds is poorly understood. RESULTS: In this study, we investigated the 3D genome organization and performed transcriptome characterization of two adipose depots (upper layer of backfat [ULB] and greater omentum [GOM]) in wild boars and Bama pigs; the latter is a typical indigenous pig in China. We found that over 95% of the A/B compartments and topologically associating domains (TADs) are stable between wild boars and Bama pigs. In contrast, more than 70% of promoter-enhancer interactions (PEIs) are dynamic and widespread, involving over a thousand genes. Alterations in chromatin structure are associated with changes in the expression of genes that are involved in widespread biological functions such as basic cellular functions, endocrine function, energy metabolism and the immune response. Approximately 95% and 97% of the genes associated with reorganized A/B compartments and PEIs in the two pig breeds differed between GOM and ULB, respectively. CONCLUSIONS: We reported 3D genome organization in adipose depots from different pig breeds. In a comparison of Bama pigs and wild boar, large-scale compartments and TADs were mostly conserved, while fine-scale PEIs were extensively reorganized. The chromatin architecture in these two pig breeds was reorganized in an adipose depot-specific manner. These results contribute to determining the regulatory mechanism of phenotypic differences between Bama pigs and wild boar.

8.
Nat Commun ; 13(1): 131, 2022 01 10.
Article de Anglais | MEDLINE | ID: mdl-35013308

RÉSUMÉ

Folliculogenesis is a complex biological process involving a central oocyte and its surrounding somatic cells. Three-dimensional chromatin architecture is an important transcription regulator; however, little is known about its dynamics and role in transcriptional regulation of granulosa cells during chicken folliculogenesis. We investigate the transcriptomic dynamics of chicken granulosa cells over ten follicular stages and assess the chromatin architecture dynamics and how it influences gene expression in granulosa cells at three key stages: the prehierarchical small white follicles, the first largest preovulatory follicles, and the postovulatory follicles. Our results demonstrate the consistency between the global reprogramming of chromatin architecture and the transcriptomic divergence during folliculogenesis, providing ample evidence for compartmentalization rearrangement, variable organization of topologically associating domains, and rewiring of the long-range interaction between promoter and enhancers. These results provide key insights into avian reproductive biology and provide a foundational dataset for the future in-depth functional characterization of granulosa cells.


Sujet(s)
Protéines aviaires/génétique , Poulets/génétique , Chromatine/ultrastructure , Cellules de la granulosa/métabolisme , Ovogenèse/génétique , Transcriptome , Animaux , Protéines aviaires/classification , Protéines aviaires/métabolisme , Poulets/croissance et développement , Poulets/métabolisme , Chromatine/composition chimique , Éléments activateurs (génétique) , Femelle , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes au cours du développement , Gene Ontology , Cellules de la granulosa/cytologie , Annotation de séquence moléculaire , Ovocytes/cytologie , Ovocytes/métabolisme , Régions promotrices (génétique)
9.
Plants (Basel) ; 10(2)2021 Feb 04.
Article de Anglais | MEDLINE | ID: mdl-33557310

RÉSUMÉ

Plant production in a plant factory is an innovative and smart idea to grow food anytime, anywhere, regardless of the outer environment. However, potato pre-basic seed tuber (PBST) production in a plant factory is a comparatively new initiative. Therefore, the aim of this study was to optimize the artificial LED light spectrum to produce PBST in a plant factory. Two potato varieties such as Golden king (V48) and Chungang (V41) were grown in soil substrate under different combination of artificial LED light combinations (such as red+blue+far-red, red+blue+white, blue+far-red, blue+white, red+far-red, and red+white) maintaining photosynthetic photon flux density (PPFD) of 100 mol m-2s-1, temperature 23/15 °C (day/night), and relative humidity 70%. The study revealed that, overall, potato plant growth (viz.; plant height, node number, leaf number, leaf length and width, fresh and dry weight) was enhanced by the red+far red light for both potato varieties. The total seed tuber number per plant was higher in red+blue+white light for V48, and red+far-red for V41. The fresh tuber weight was the highest in the red+blue+far-red light for V48 and red+blue+white for V41. The highest accumulated photosynthetic pigment (total Chlorophyll, Chlorophyll a, b and Carotenoid) was observed in red+blue+white light for both varieties. The total carbohydrate content and total sucrose content were higher in red+blue+far red and red +far red light treatment for V48 and V41, respectively. Finally, considering all factors, it is concluded that the red+blue+white light combination is deemed to be appropriate for the potato PBST production in plant factory conditions.

10.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-737308

RÉSUMÉ

Objective To launch systematic research on long-term asymptomatic hyperuricemia (HUA) from hemorheological viewpoint,so as to provide references for clinical treatment of asymptomatic HUA.Methods Twenty rats were randomly and evenly divided into normal control group and model group.The rats were intraperitoneally injected with 250 mg/(kg · d) oxonate for 8 weeks to induce the model of asymptomatic HUA.The blood samples were obtained to measure the serum uric acid,hemorheological parameters,oxidative and anti-oxidative indices.Results The aggregation index,haemolysis rate,serum xanthine oxidase (XOD),plasma fibrinogen and blood viscosity significantly increased,while the orientation index,electrophoresis rate,serum superoxide dismutase (SOD),activated partial thromboplastin time (APTT) and prothrombin time (PT) significantly induced.Conclusions The asymptomatic HUA can lead to more serious oxidative stress,deteriorate the hemorheological parameters of red blood cells in rats,and induce higher blood viscosity and coagulation status.The research findings indicate that asymptomatic HUA should be correctly understood and timely intervened in clinical diagnosis.

11.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-735840

RÉSUMÉ

Objective To launch systematic research on long-term asymptomatic hyperuricemia (HUA) from hemorheological viewpoint,so as to provide references for clinical treatment of asymptomatic HUA.Methods Twenty rats were randomly and evenly divided into normal control group and model group.The rats were intraperitoneally injected with 250 mg/(kg · d) oxonate for 8 weeks to induce the model of asymptomatic HUA.The blood samples were obtained to measure the serum uric acid,hemorheological parameters,oxidative and anti-oxidative indices.Results The aggregation index,haemolysis rate,serum xanthine oxidase (XOD),plasma fibrinogen and blood viscosity significantly increased,while the orientation index,electrophoresis rate,serum superoxide dismutase (SOD),activated partial thromboplastin time (APTT) and prothrombin time (PT) significantly induced.Conclusions The asymptomatic HUA can lead to more serious oxidative stress,deteriorate the hemorheological parameters of red blood cells in rats,and induce higher blood viscosity and coagulation status.The research findings indicate that asymptomatic HUA should be correctly understood and timely intervened in clinical diagnosis.

12.
Journal of Medical Biomechanics ; (6): E088-E091, 2017.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-803816

RÉSUMÉ

Objective To launch systematic research on long-term asymptomatic hyperuricemia (HUA) from hemorheological viewpoint, so as to provide references for clinical treatment of asymptomatic HUA. Methods Twenty rats were randomly and evenly divided into normal control group and model group. The rats were intraperitoneally injected with 250 mg/(kg•d) oxonate for 8 weeks to induce the model of asymptomatic HUA. The blood samples were obtained to measure the serum uric acid, hemorheological parameters, oxidative and anti-oxidative indices. Results The aggregation index, haemolysis rate, serum xanthine oxidase (XOD), plasma fibrinogen and blood viscosity significantly increased, while the orientation index, electrophoresis rate, serum superoxide dismutase (SOD), activated partial thromboplastin time (APTT) and prothrombin time (PT) significantly induced. Conclusions The asymptomatic HUA can lead to more serious oxidative stress, deteriorate the hemorheological parameters of red blood cells in rats, and induce higher blood viscosity and coagulation status. The research findings indicate that asymptomatic HUA should be correctly understood and timely intervened in clinical diagnosis.

13.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(5): 3118-9, 2016 09.
Article de Anglais | MEDLINE | ID: mdl-25630725

RÉSUMÉ

In this study, the mitochondrial genome of Asian golden cat (Catopuma temminckii) is sequenced. The mitochondrial genome was 16,985 bp long, including 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, 1 control region and 1 origin of light-strand replication. The overall base composition of the mitochondrial genome was 32.76% A, 27.49 % T, 25.75 % C, and 13.99 % G. The complete mitochondrial genome of Catopuma temminckii could contribute to understanding taxonomic status and phylogenetic relationship of genus Catopuma.


Sujet(s)
Felidae/génétique , Génome mitochondrial , Animaux , Composition en bases nucléiques , Felidae/classification , Cadres ouverts de lecture , Phylogenèse , ARN ribosomique/génétique , ARN de transfert/génétique
14.
Acta Chim Slov ; 61(3): 629-36, 2014.
Article de Anglais | MEDLINE | ID: mdl-25286220

RÉSUMÉ

Two new oxidovanadium(V) complexes with hydrazone ligands and hydroxamate ligands were synthesized and characterized by IR and (1)H NMR spectroscopy, elemental analysis and single crystal X-ray diffraction. The coordination sphere of each V atom is octahedral, constructed from three donor atoms of the hydrazone ligand, two donor atoms of the hydroxamate ligand, and one oxido oxygen. Both complexes show effective catalytic oxidation properties for the oxidation of cyclohexene, cyclopentene and benzyl alcohol using H(2)O(2) as primary oxidant.

15.
J Laparoendosc Adv Surg Tech A ; 23(3): 246-9, 2013 Mar.
Article de Anglais | MEDLINE | ID: mdl-23379918

RÉSUMÉ

UNLABELLED: Abstract Background: In laparoscopic surgery with CO2 pneumoperitoneum, serious complications often occur for elderly patients and those who undergo long operations. These complications mainly include respiratory and circulatory system changes. In patients with tumors, release of free tumor cells into the abdominal cavity is believed to be possible. Gasless laparoscopic techniques can avoid these complications of CO2 pneumoperitoneum. Currently, the main shortcoming of gasless laparoscopic techniques is inadequate operative space. Because of this shortcoming, gasless techniques have not been widely applied in clinical practice. MATERIALS AND METHODS: We herein describe a new technique of gasless laparoscopic cholecystectomy in pigs using a self-designed umbrella-like abdominal wall-lifting device. This device lifts up the anterior abdominal wall by opening the umbrella leaf in the abdominal cavity. RESULTS: Five pigs underwent laparoscopic cholecystectomy using this technique. The operation times were 85, 40, 28, 21, and 24 minutes. The corresponding bleeding volumes were 11, 20, 5, 2, and 8 mL. CONCLUSIONS: These preliminary outcomes suggest that the umbrella-like abdominal wall-lifting technique is safe and feasible in gasless laparoscopic surgery and can provide sufficient exposure of the operative field. Further study in the form of randomized controlled trials is needed to investigate the advantages of this new technique.


Sujet(s)
Laparoscopie/instrumentation , Laparoscopie/méthodes , Paroi abdominale , Animaux , Conception d'appareillage , Mâle , Suidae , Porc miniature
16.
Int J Mol Sci ; 13(2): 2036-2047, 2012.
Article de Anglais | MEDLINE | ID: mdl-22408436

RÉSUMÉ

In order to improve the water-resistant ability of silk fibroin (SF) and SF/P(LLA-CL) blended nanofibrous scaffolds for tissue engineering applications, 75% (v/v) ethanol vapor was used to post-treat electrospun nanofibers. SEM indicated that the treated SF and SF/P(LLA-CL) nanofibrous scaffolds maintained a nanofibrous structure and possessed good water-resistant ability. Characterization of (13)C CP-MAS NMR clarified that 75% (v/v) ethanol vapor could induce SF conformation from random coil or α-helix to ß-sheet. Although the water contact showed that treated SF/P(LLA-CL) blended nanofibrous scaffolds were hydrophobic, the water uptake demonstrated that their hydrophilicity was greatly superior to those of pure P(LLA-CL) nanofibrous scaffolds. Furthermore, the treated SF/P(LLA-CL) nanofibrous scaffolds, both in dry state and wet state, could retain good mechanical properties. Therefore, 75% (v/v) ethanol vapor treatment might be an ideal method to treat SF and SF/P(LLA-CL) nanofibrous scaffolds for biomedical applications.


Sujet(s)
Éthanol/pharmacologie , Fibroïne/effets des médicaments et des substances chimiques , Polyesters/composition chimique , Structures d'échafaudage tissulaires/composition chimique , Techniques de culture cellulaire/instrumentation , Éthanol/composition chimique , Fibroïne/composition chimique , Interactions hydrophobes et hydrophiles/effets des médicaments et des substances chimiques , Nanofibres/composition chimique , Soie/composition chimique , Soie/effets des médicaments et des substances chimiques , Propriétés de surface/effets des médicaments et des substances chimiques , Résistance à la traction/effets des médicaments et des substances chimiques , Ingénierie tissulaire , Volatilisation , Mouillabilité/effets des médicaments et des substances chimiques
17.
Int J Mol Sci ; 12(4): 2187-99, 2011.
Article de Anglais | MEDLINE | ID: mdl-21731435

RÉSUMÉ

The native extracellular matrix (ECM) is composed of a cross-linked porous network of multifibril collagens and glycosaminoglycans. Nanofibrous scaffolds of silk fibroin (SF) and hydroxybutyl chitosan (HBC) blends were fabricated using 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) and trifluoroacetic acid (TFA) as solvents to biomimic the native ECM via electrospinning. Scanning electronic microscope (SEM) showed that relatively uniform nanofibers could be obtained when 12% SF was blended with 6% HBC at the weight ratio of 50:50. Meanwhile, the average nanofibrous diameter increased when the content of HBC in SF/HBC blends was raised from 20% to 100%. Fourier transform infrared spectra (FTIR) and (13)C nuclear magnetic resonance (NMR) showed SF and HBC molecules existed in hydrogen bonding interactions but HBC did not induce conformation of SF transforming from random coil form to ß-sheet structure. X-ray diffraction (XRD) confirmed the different structure of SF/HBC blended nanofibers from both SF and HBC. Thermogravimetry-Differential thermogravimetry (TG-DTG) results demonstrated that the thermal stability of SF/HBC blend nanofibrous scaffolds was improved. The results indicated that the rearrangement of HBC and SF molecular chain formed a new structure due to stronger hydrogen bonding between SF and HBC. These electrospun SF/HBC blended nanofibers may provide an ideal tissue engineering scaffold and wound dressing.


Sujet(s)
Chitosane/composition chimique , Fibroïne/composition chimique , Nanofibres/composition chimique , Liaison hydrogène , Structure secondaire des protéines , Soie/composition chimique , Température , Thermogravimétrie , Ingénierie tissulaire , Diffraction des rayons X
18.
Nanoscale Res Lett ; 6(1): 67, 2011 Jan 12.
Article de Anglais | MEDLINE | ID: mdl-21711603

RÉSUMÉ

Calcium phosphate is the most important inorganic constituent of biological tissues, and synthetic calcium phosphate has been widely used as biomaterials. In this study, a facile method has been developed for the fabrication of amorphous calcium phosphate (ACP)/polylactide-block-monomethoxy(polyethyleneglycol) hybrid nanoparticles and ACP porous nanospheres. Europium-doping is performed to enable photoluminescence (PL) function of ACP porous nanospheres. A high specific surface area of the europium-doped ACP (Eu3+:ACP) porous nanospheres is achieved (126.7 m2/g). PL properties of Eu3+:ACP porous nanospheres are investigated, and the most intense peak at 612 nm is observed at 5 mol% Eu3+ doping. In vitro cytotoxicity experiments indicate that the as-prepared Eu3+:ACP porous nanospheres are biocompatible. In vitro drug release experiments indicate that the ibuprofen-loaded Eu3+:ACP porous nanospheres show a slow and sustained drug release in simulated body fluid. We have found that the cumulative amount of released drug has a linear relationship with the natural logarithm of release time (ln(t)). The Eu3+:ACP porous nanospheres are bioactive, and can transform to hydroxyapatite during drug release. The PL properties of drug-loaded nanocarriers before and after drug release are also investigated.

19.
Neurochem Res ; 36(10): 1896-902, 2011 Oct.
Article de Anglais | MEDLINE | ID: mdl-21611833

RÉSUMÉ

Substance P (SP) is a neuropeptide that plays an important role in inflammation, respiration, pain, aggression, anxiety, and learning and memory mainly through its high affinity neurokinin 1 receptor (NK1R). The marginal division (MrD) is a pan-shaped subdivision in the caudomedial margin of the neostriatum in the mammalian brain and is known to be involved in learning and memory. We studied the expression of SP, NK1R and NK1R mRNA in the rat striatum by immunohistochemistry, immunofluorescence and in situ hybridization, and found that the levels of SP, NK1R protein and NK1R mRNA were high in the cell bodies, fibers and terminals of neurons in the neostriatum, especially in the MrD. Knocking down NK1R activity in the MrD by using an antisense oligonucleotide against NK1R mRNA inhibited learning and memory in a Y-maze behavioral test. Our results show that NK1R mediates the role of SP in the MrD in learning and memory.


Sujet(s)
Apprentissage/physiologie , Mémoire/physiologie , Néostriatum/anatomie et histologie , Néostriatum/physiologie , Récepteur de la neurokinine 1/métabolisme , Substance P/métabolisme , Animaux , Comportement animal/physiologie , Mâle , Rats , Récepteur de la neurokinine 1/génétique
20.
J Biomater Sci Polym Ed ; 22(8): 1099-113, 2011.
Article de Anglais | MEDLINE | ID: mdl-20615315

RÉSUMÉ

The aim of this study is to investigate cross-linked gelatin-chitosan nanofibers produced by means of electrospinning. Gelatin and chitosan nanofibers were electrospun and then cross-linked by glutaraldehyde (GTA) vapor at room temperature. Scanning electron microscopy (SEM) images showed that the cross-linked mats could keep their nanofibrous structure after being soaked in deionized water at 37° C. The cross-linking mechanism was discussed based on FT-IR results. The two main mechanisms of cross-linking for chitosan and gelatin-chitosan complex are Schiff base reaction and acetalization reaction. For gelatin, the mechanism of cross-linking was Schiff base reaction. The mechanical properties of nanofibrous mats were improved after cross-linking. The biocompatibility of electrospun nanofibrous mats after cross-linking was investigated by the viability of porcine iliac endothelial cells (PIECs). The morphologies of PIECs on the cross-linked nanofibrous mats were observed by SEM. In addition, proliferation of PIECs was tested with the method of methylthiazol tetrazolium (MTT) assay. The results indicate that gelatin-chitosan nanofibrous mats could be a promising candidate for tissue-engineering scaffolds.


Sujet(s)
Chitosane/composition chimique , Gélatine/composition chimique , Nanofibres/composition chimique , Ingénierie tissulaire/méthodes , Structures d'échafaudage tissulaires/composition chimique , Animaux , Spectroscopie par résonance magnétique , Microscopie électronique à balayage , Spectroscopie infrarouge à transformée de Fourier , Suidae
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