Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 826
Filtrar
Filtros adicionais











Intervalo de ano
1.
BMC Genomics ; 20(1): 688, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477016

RESUMO

BACKGROUND: Pekin duck is an important animal model for its ability for fat synthesis and deposition. However, transcriptional dynamic regulation of adipose differentiation driven by complex signal cascades remains largely unexplored in this model. This study aimed to explore adipogenic transcriptional dynamics before (proliferation) and after (differentiation) initial preadipocyte differentiation in ducks. RESULTS: Exogenous oleic acid alone successfully induced duck subcutaneous preadipocyte differentiation. We explored 36 mRNA-seq libraries in order to study transcriptome dynamics during proliferation and differentiation processes at 6 time points. Using robust statistical analysis, we identified 845, 652, 359, 2401 and 1933 genes differentially expressed between -48 h and 0 h, 0 h and 12 h, 12 h and 24 h, 24 h and 48 h, 48 h and 72 h, respectively (FDR < 0.05, FC > 1.5). At the proliferation stage, proliferation related pathways and basic cellular and metabolic processes were inhibited, while regulatory factors that initiate differentiation enter the ready-to-activate state, which provides a precondition for initiating adipose differentiation. According to weighted gene co-expression network analysis, pathways positively related to adipogenic differentiation are significantly activated at the differentiation stage, while WNT, FOXO and other pathways that inhibit preadipocyte differentiation are negatively regulated. Moreover, we identified and classified more than 100 transcription factors that showed significant changes during differentiation, and found novel transcription factors that were not reported to be related to preadipoctye differentiation. Finally, we manually assembled a proposed regulation network model of subcutaneous preadipocyte differentiation base on the expression data, and suggested that E2F1 may serve as an important link between the processes of duck subcutaneous preadipocyte proliferation and differentiation. CONCLUSIONS: For the first time we comprehensively analyzed the transcriptome dynamics of duck subcutaneous preadipocyte proliferation and differentiation. The current study provides a solid basis for understanding the synthesis and deposition of subcutaneous fat in ducks. Furthermore, the information generated will allow future investigations of specific genes involved in particular stages of duck adipogenesis.

2.
Dysphagia ; 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31463803

RESUMO

Denture impacted in the esophagus of adults has been a complex foreign body for otolaryngologists. We reviewed clinical characteristics, diagnosis, and treatment of these patients and evaluated computed tomography (CT) scans to identify a better method of dealing with such tricky situations. Twenty-nine patients who underwent rigid esophagoscopy were included in this retrospective study conducted at the University hospital. The patients underwent preoperative tests and examinations, including complete blood count, blood type and coagulation, electrocardiogram, and CT. The commonest symptoms were retrosternal pain, dysphagia, and odynophagia. Duration of the foreign body impacted within 24 h was 65.5%. CT findings revealed that 4 of 24 cases had complications in the upper esophagus, with 3 of the 4 cases in the mid-esophagus and 1 in the lower esophagus. Complications were related to the duration and location of the obstruction (P < 0.05). The location and complications based on CT findings were coherent with rigid esophagoscopy findings. Denture impaction in the esophagus can be fatal. Early intervention is crucial for prognosis. CT is used for diagnosing and guiding doctors in managing. The commonest location of impacted dentures was the upper esophagus with a lower incidence of complications. The incidence of an impacted denture in the mid-esophagus was low but with a high risk of complications. The incidence of an impacted denture in the lower esophagus was rare. Surgery and proper treatment ensure a good prognosis.

3.
Biomaterials ; 219: 119378, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31382209

RESUMO

Pro-inflammatory M1 macrophage is identified as a prominent component initializing the progress of vulnerable atherosclerotic plaque. Here, we constructed anti-MARCO NaGdF4:Yb,Er@NaGdF4 upconversion nanoparticles (UCNPs) by conjugating polyclonal MARCO antibody to the surface of NaGdF4:Yb,Er@NaGdF4via condensation reaction. UCNPs displayed highly mono-dispersion with average sizes of 26.7 ±â€¯0.8 nm and favorable biocompatibility. In vivo upconversion optical imaging revealed that distinctive fluorescence signal could be observed in the regions of carotid artery 10 min post-injection, reached peak value at 1 h and decreased back to baseline at 24 h post-injection. The carotid artery wall demonstrated high signal intensity on T1-weighted MR images after anti-MARCO UCNPs injection, as determined by 7.0T MRI. Immunofluorescence staining of tissue section of carotid artery revealed that MARCO was highly abundant in shoulder regions of plaque. Anti-MARCO UCNPs is a promising optical/MRI dual-modality imaging probe which can non-invasively reflect M1 phenotype macrophages behavior in vivo.

4.
BMC Genet ; 20(1): 67, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412760

RESUMO

BACKGROUND: Egg production is the most economically-important trait in layers as it directly influences benefits of the poultry industry. To better understand the genetic architecture of egg production, we measured traits including age at first egg (AFE), weekly egg number (EN) from onset of laying eggs to 80 weeks which was divided into five stage (EN1: from onset of laying eggs to 23 weeks, EN2: from 23 to 37 weeks, EN3: from 37 to 50 weeks, EN4: from 50 to 61 weeks, EN5: from 61 to 80 weeks) based on egg production curve and total egg number across the whole laying period (Total-EN). Then we performed genome-wide association studies (GWAS) in 1078 Rhode Island Red hens using a linear mixed model. RESULTS: Estimates of pedigree and SNP-based genetic parameter showed that AFE and EN1 exhibited high heritability (0.51 ± 0.09, 0.53 ± 0.08), while the h2 for EN in other stages varied from low (0.07 ± 0.04) to moderate (0.24 ± 0.07) magnitude. Subsequently, seven univariate GWAS for AFE and ENs were carried out independently, from which a total of 161 candidate SNPs located on GGA1, GGA2, GGA5, GGA6, GGA9 and GGA24 were identified. Thirteen SNP located on GGA6 were associated with AFE and an interesting gene PRLHR that may affect AFE through regulating oxytocin secretion in chickens. Sixteen genome-wide significant SNPs associated with EN3 were in a strong linkage disequilibrium (LD) region spanning from 117.87 Mb to 118.36 Mb on GGA1 and the most significant SNP (rs315777735) accounted for 3.57% of phenotypic variance. Genes POLA1, PDK3, PRDX4 and APOO identified by annotating sixteen genome-wide significant SNPs can be considered as candidates associated with EN3. Unfortunately, our study did not find any candidate gene for the total egg number. CONCLUSIONS: Findings in our study could provide promising genes and SNP markers to improve egg production performance based on marker-assisted breeding selection, while further functional validation is still needed in other populations.

5.
Biomed Pharmacother ; 117: 109178, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31387193

RESUMO

OBJECTIVE: The purpose of this study is to illustrate the therapeutic effect of which kind of polarized macrophages-based cell therapy in hepatic fibrosis caused by cystic echinococcosis. METHODS: The isolation culture and polarization induction of mouse bone marrow-derived macrophages (BMDM) are established in an in vitro environment. A model of Echinococcus granulosus infection is established by direct injection of the Echinococcus granulosus suspension into the left hepatic lobe. The macrophages are labeled in vitro and the localization of the returned macrophages in the liver of the mice is determined by in vivo tracing. Macrophages of different polarization types are injected into the successfully modeled mice through the tail vein, and the results of HE, Masson, Sirius Red, Desmin immunohistochemistry and Hyp content are inspected to evaluate by liver tissue. Liver pathology and changes in the degree of fibrosis. RESULTS: Bone marrow-derived macrophages have been successfully obtained and induced into M1 and M2 macrophages by different conditions; a model of Echinococcus granulosus infection was successfully established. Macrophages labeled in vitro were returned to the model through the tail vein and they can be located in the liver; a variety of experimental results show that compared with the PBS group, the degree of fibrosis in the M0 group and the M1 group have been reduced, with statistical difference, and the M1 is better than M0 in terms of the therapeutic effect. There is no significant change in the degree of fibrosis in the M2 group. CONCLUSION: Both M1 and M0 macrophages can alleviate liver fibrosis caused by persistent infection of Echinococcus granulosus, but the treatment effect of M1 macrophages is more significant. Cell therapy based on M1 macrophages may be a new idea for treating liver fibrosis caused by persistent infection of Echinococcus granulosus.

7.
Poult Sci ; 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31424521

RESUMO

For healthy development, an avian embryo needs the nutritional and functional molecules maternally deposited in avian eggs. Egg white not only provides nutritional components but also exhibits functional properties, such as defenses against microbial invasion. However, the roles of the more detailed messages in embryo development remain unclear. In this study, a tandem mass tag labeling quantitation approach was used to innovatively identify the differential proteins in the egg whites of fresh eggs produced by hens with divergent high/low hatchability and in the egg whites of embryonated eggs with healthy and dead embryos. A total of 378 proteins were quantified in egg white, which is the most complete proteome identified for egg white to date, and up to 102 differential proteins were identified. GO enrichment, pathway, and hierarchical clustering analysis revealed some of the differential proteins that are the main participants in several biological processes, including blood coagulation, intermediate filament, antibacterial activity, and neurodevelopment. A list of 11 putative protein biomarkers, such as keratin (KRT19, KRT12, KRT15, and KRT6A), which is involved in cell architecture, and fibrinogen (fibrinogen alpha chain, fibrinogen beta chain, and fibrinogen gamma chain), which is related to blood coagulation, were ultimately screened. The current study screened egg white proteins that can predict low hatchability and embryonic death and deciphered the role of these proteins in embryonic development, which is meaningful for the comprehensive understanding of embryonic growth.

8.
J BUON ; 24(3): 1128-1136, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31424671

RESUMO

PURPOSE: Colorectal cancer (CRC) is a common malignancy which has a high mortality rate around the world. The advancement of new therapeutic strategies is crucial for the efficient treatment of CRC. Many miRNAs play a central role in the progression of cancer cells. There are still few studies on miR-335-5p and CRC. In this study, the potential of miR-335-5p in CRC development and progression was explored. METHODS: The expression level of miR-335-5p in CRC cell lines and tissues was detected by quantitative real-time polymerase chain reaction (qRT-PCR) assay. Cell counting kit-8 (CCK8) assay and colony formation assay were applied for evaluating the ability of cell proliferation. Wound healing assay and Transwell assay were applied for detecting cell migration and invasion ability. Moreover, dual luciferase reporter assay was performed to validate if lactic dehydrogenase B (LDHB) is a downstream target of miR-335-5p. Western blotting was used to estimate the expression of protein. RESULTS: The expression of miR-335-5p was significantly low in CRC tissues and cells. To investigate the function of miR-335-5p in CRC, two CRC cell lines (HCT-116 and SW620) were selected for further experiments. After transfection with mimics and inhibitor to up-regulate or down-regulate miR-335-5p, it was found that overexpression of miR-335-5p obviously decreased cell proliferation and inhibited migration ability and invasion, while the knockdown of miR-335-5p could obtain the opposite results. Then it was validated in dual luciferase reporter assay that LDHB could be a potential directive target gene of miR-335-5p. Moreover, the rescue assay confirmed that miR-335-5p executed its function as a tumor suppressor gene through targeting LDHB in CRC. CONCLUSIONS: To sum up, the present study demonstrated that miR-335-5p regulates cell proliferation, migration as well as invasion of CRC cells through down-regulating LDHB, and demonstrated that miR-335-5p/LDHB axis may be an underlying therapeutic strategy in CRC.

9.
Genes (Basel) ; 10(8)2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31416226

RESUMO

Cytochrome P450 (CYP) superfamily enzymes are broadly involved in a variety of physiological and toxicological processes. However, genome-wide analysis of this superfamily has never been investigated in the chicken genome. In this study, genome-wide analyses identified 45 chicken CYPs (cCYPs) from the chicken genome, and their classification and evolutionary relationships were investigated by phylogenetic, conserved protein motif, and gene structure analyses. The comprehensive evolutionary data revealed several remarkable characteristics of cCYPs, including the highly divergent and rapid evolution of the cCYPs, and the loss of cCYP2AF in the chicken genome. Furthermore, the cCYP expression profile was investigated by RNA-sequencing. The differential expression of cCYPs in developing embryos revealed the involvement of cCYPs in embryonic development. The significantly regulated cCYPs suggested its potential role in hepatic metabolism. Additionally, 11 cCYPs, including cCYP2AC1, cCYP2C23a, and cCYP2C23b, were identified as estrogen-responsive genes, which indicates that these cCYPs are involved in the estrogen-signaling pathway. Meanwhile, an expression profile analysis highlights the divergent role of different cCYPs. These data expand our view of the phylogeny and evolution of cCYPs, provide evolutionary insight, and can help elucidate the roles of cCYPs in physiological and toxicological processes in chicken.

10.
Neurosci Bull ; 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31376056

RESUMO

Abnormal postoperative neurobehavioral performance (APNP) is a common phenomenon in the early postoperative period. The disturbed homeostatic status of metabolites in the brain after anesthesia and surgery might make a significant contribution to APNP. The dynamic changes of metabolites in different brain regions after anesthesia and surgery, as well as their potential association with APNP are still not well understood. Here, we used a battery of behavioral tests to assess the effects of laparotomy under isoflurane anesthesia in aged mice, and investigated the metabolites in 12 different sub-regions of the brain at different time points using proton nuclear magnetic resonance (1H-NMR) spectroscopy. The abnormal neurobehavioral performance occurred at 6 h and/or 9 h, and recovered at 24 h after anesthesia/surgery. Compared with the control group, the altered metabolite of the model group at 6 h was aspartate (Asp), and the difference was mainly displayed in the cortex; while significant changes at 9 h occurred predominantly in the cortex and hippocampus, and the corresponding metabolites were Asp and glutamate (Glu). All changes returned to baseline at 24 h. The altered metabolic changes could have occurred as a result of the acute APNP, and the metabolites Asp and Glu in the cortex and hippocampus could provide preliminary evidence for understanding the APNP process.

11.
Fish Shellfish Immunol ; 93: 153-160, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31319206

RESUMO

Cathepsins are the best-known group of proteases in lysosomes, playing a significant role in immune responses. Cathepsin K (CTSK) is abundantly and selectively expressed in osteoclasts, dendritic cells and monocyte-derived macrophages, where it is involved in ECM degradation and bone remodeling. A growing body of evidences have indicated the vital roles of cathepsin K in innate immune responses. Here, one CTSK gene was captured in turbot (SmCTSK) with a 993 bp open reading frame (ORF). The genomic structure analysis showed that SmCTSK had 7 exons similar to other vertebrate species. The syntenic analysis revealed that CTSK had the same neighboring genes across all the selected species, which suggested the synteny encompassing CTSK region was conserved during vertebrate evolution. Subsequently, SmCTSK was widely expressed in all the examined tissues, with the highest expression level in spleen and the lowest expression level in liver. In addition, SmCTSK was significantly down-regulated in intestine following Gram-negative bacteria Vibrio anguillarum immersion challenge, but up-regulated in three tissues (gill, skin and intestine) following Gram-positive bacteria Streptococcus iniae immersion challenge. Finally, the rSmCTSK showed strong binding ability to all the examined microbial ligands. Taken together, our results suggested SmCTSK played vital roles in fish innate immune responses against infection. However, the knowledge of SmCTSK is still limited in teleost species, further studies should be carried out to better characterize its comprehensive roles in teleost mucosal immunity.

12.
Biomed Pharmacother ; 118: 109254, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31357080

RESUMO

Multiple myeloma is the second largest malignant tumor of the blood system. Proteasome inhibitors (PIs) currently are effective drugs for some myeloma patients, but their prognosis varies. We extracted the transcriptome expression data and clinical information of myeloma patients from MMRF CoMMpass database, and used the Random Survival Forest Variable Hunting (RSF-VH) algorithm to select 6 highly prognosis-related genes and to develop a 6-genes scoring model, by which the risk score predicted were significantly associated with the progress-free survival (PFS, P<0.001). The median PFS of the high-risk group is 21 months, while it is 29 months in the low-risk group. The scoring model was further validated in the testing cohort. Furthermore, Analysis revealed that the risk score performed better in predicting the multiple myeloma patients' prognosis than the existed staging system, including R-ISS. The risk score is independent with the most existed clinical risk indicators, and the prognostic effectiveness of 6-genes scoring model is homogenous in patients with different clinical observations. Further bioinformatic analysis revealed that the risk score is not only significantly associated with multiple myeloma-related pathways, including immune response, but also with the infiltration of many kinds of immune cells that associated with clinical malignancy. Collectively, the model we developed using one lincRNA and five mRNAs is a robust and effective indicator for myeloma patients' prognosis undergoing proteasome inhibitors therapy.

13.
Food Funct ; 10(8): 5046-5058, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31359016

RESUMO

Human and bovine milk fat globule membrane (MFGM) proteins have been identified and characterized; however, their glycosylation during lactation remains unclear. We adopted a glycoproteomics approach to profile and compare MFGM N-glycoproteomes in human and bovine milk during lactation. A total of 843, 718, 614, and 273 N-glycosite peptides corresponding to 465, 423, 334, and 176 glycoproteins were identified in human colostrum, human mature milk, bovine colostrum, and bovine mature milk, respectively. The biological functions of these MFGM N-glycoproteins were revealed through bioinformatics. Substantial differences were observed between human and bovine milk, and immune-related MFGM N-glycoproteins varied between colostrum and mature milk from both species. Our results expand current knowledge of MFGM N-glycoproteomes, and further demonstrate the complexity and biological functions of MFGM N-glycosylation. These data can provide references for the application of bovine MFGM N-glycoproteins in infant formula to resemble human milk and in functional foods.

14.
Molecules ; 24(13)2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31269660

RESUMO

Pesticides vary in the level of poisonousness, while a conventional rapid test card only provides a general "absence or not" solution, which cannot identify the various genera of pesticides. In order to solve this problem, we proposed a seven-layer paper-based microfluidic chip, integrating the enzyme acetylcholinesterase (AChE) and chromogenic reaction. It enables on-chip pesticide identification via a reflected light intensity spectrum in time-sequence according to the different reaction efficiencies of pesticide molecules and assures the optimum temperature for enzyme activity. After pretreatment of figures of reflected light intensity during the 15 min period, the figures mainly focused on the reflected light variations aroused by the enzyme inhibition assay, and thus, the linear discriminant analysis showed satisfying discrimination of imidacloprid (Y = -1.6525X - 139.7500), phorate (Y = -3.9689X - 483.0526), and avermectin (Y = -2.3617X - 28.3082). The correlation coefficients for these linearity curves were 0.9635, 0.8093, and 0.9094, respectively, with a 95% limit of agreement. Then, the avermectin class chemicals and real-world samples (i.e., lettuce and rice) were tested, which all showed feasible graphic results to distinguish all the chemicals. Therefore, it is feasible to distinguish the three tested kinds of pesticides by the changes in the reflected light spectrum in each min (15 min) via the proposed chip with a high level of automation and integration.

15.
Medicine (Baltimore) ; 98(27): e15990, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31277090

RESUMO

BACKGROUND: Recent studies have demonstrated that coronary microcirculation dysfunction (CMVD) is closely correlated with adverse clinical outcomes. In this study, quantitative stress myocardial contrast echocardiography (MCE) was used to evaluate the CMVD and to investigate its association with the prognosis of patients with nonobstructive coronary artery disease (CAD). MATERIAL AND METHODS: From 2006 to 2014, 227 consecutive patients with chest pain and a diagnostic coronary angiography without significant coronary artery stenosis (<50%) who underwent adenosine triphosphate disodium (ATP) stress MCE were enrolled. Quantitative MCE measurements were analyzed using replenishment curves. RESULTS: Median follow-up time of this study was 5.3 years. Predictors of impaired coronary flow reserve (CFR) were smoking, diabetes, high apolipoprotein B, high low-density lipoprotein, serum uric acid, and low apolipoprotein A. During follow-up, 22 patients were reported to have 30 cardiac events (21 unstable angina, 3 nonfatal myocardial infarctions, 6 percutaneous coronary interventions). Using multivariate analysis, abnormal ß reserve (≤1.6), impaired CFR (≤2.0), and diabetes were independent predictors of primary endpoint events in patients with nonobstructive CAD (P < .05). Multivariate analysis showed that CFR ≤2.0 (odds ratio [OR] =  25.21, 95% confidence interval [CI]: 3.01-182.32; P = .003), ß reserve ≤1.6 (OR = 29.96, 95% CI: 3.5-241.27; P = .002), and diabetic (OR = 33.11, 95% CI: 3.65-300.02; P = .002) significantly increased the risk of the primary endpoint events. CONCLUSIONS: ATP stress quantitative MCE is a feasible and effective method to evaluate microcirculation abnormalities in human coronary arteries and it can be used for the clinical analysis, risk stratification, and treatment of early CAD.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Ecocardiografia sob Estresse/métodos , Ecocardiografia/métodos , Microcirculação/fisiologia , Trifosfato de Adenosina/administração & dosagem , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Fatores de Risco
16.
J Sci Food Agric ; 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31328271

RESUMO

BACKGROUND: Rice smut and rice blast are listed as two of the three major diseases of rice. Owing to the small size and similar structure of rice blast and rice smut spores, traditional microscopic methods are troublesome to detect them. Therefore, this paper uses microscopy image identification based on the synergistic judgment of texture and shape features and the decision tree-confusion matrix method. RESULTS: The distance transformation-Gaussian filtering-watershed algorithm method was proposed to separate the adherent rice blast spores, and the accuracy was increased by about 10%. Four shape features (area, perimeter, ellipticity, complexity) and three texture features (entropy, homogeneity, contrast) were selected for decision-tree model classification. The confusion-matrix algorithm was used to calculate the classification accuracy, in which global accuracy is 82% and the Kappa coefficient is 0.81. At the same time, the detection accuracy is as high as 94%. CONCLUSIONS: The synergistic judgment of texture and shape features and the decision tree-confusion matrix method can be used to detect rice disease quickly and precisely. The proposed method can be combined with a spore trap, which is vital to devise strategies early and to control rice disease effectively. © 2019 Society of Chemical Industry.

17.
Poult Sci ; 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31287885

RESUMO

Poultry eggs from different species varied significantly, due to their divergent process of evolution. However, the information on egg characteristics has been limited mostly to chicken. The current study compared the egg quality, albumen physical and nutritional property for domesticated chicken, duck, goose, turkey, quail, and pigeon. Egg quality traits among different species differed significantly, such as egg weight (from 11 to 139 g), egg shape (from 1.28 to 1.44), proportion of yolk (from 19.3 to 37.9%), and breaking strength (from 0.91 to 8.04 kg/cm2). For the physical property of albumen gel, pigeon egg was the most special one. The albumen gel of pigeon egg had a transparent appearance (A = 1.23), and it had the highest hardness (121.7 g) and water-holding capacity (96%) but a medium level of total cutting work (440 g⋅s). Hence, it was easy for deformation but was hard to cut off when external force was applied. For nutritional compositions of egg albumen, goose egg had the highest moisture (89.21%) and lowest crude protein (8.5%) contents. Specific to amino acid, glutamic acid was found the most abundant in albumen of all six species. Egg albumen of turkey had the highest quantity of essential amino acids (EAA) and total amino acids (TAA), while duck and goose had relatively higher EAA/TAA ratios. Both PCA and cluster analysis revealed the high similarity of amino acid composition between duck and goose, and among quail, turkey, and chicken. The comparative data will improve the understanding of egg qualities of major poultry species and can be helpful in technological application of egg albumen.

18.
PLoS One ; 14(7): e0220054, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31339918

RESUMO

In this study, we compared the antibacterial effectivity of the eggs of six precocial and four altricial bird species using Escherichia coli, based on their eggshell traits. The ultrastructure of eggshell was observed using a scanning electron microscope (SEM). According to SEM results, eggs from precocial birds (chicken, turkey, quail, duck, ostrich, and goose) had cuticle on the eggshells, while eggs from altricial birds (pigeon, budgerigar, munia, and canary) did not. The environment/selection pressure may induce the divergent evolution process in eggs of precocial and altricial birds. The E. coli experiment results showed that chicken, turkey, quail, duck, and goose eggs, with a high cuticle opacity, exhibited a much lower E. coli penetration rate. In contrast, the eggs with poor (ostrich) or without (pigeon, budgerigar, munia, and canary) cuticle exhibited a higher penetration rate. It is suggested that cuticle is a main barrier against bacterial penetration in precocial birds' eggs. Turkey and quail eggs showed the lowest E. coli contamination rate (3.33% and 2.22%, respectively), probably because of the tightly connected nanosphere structure on their cuticle. As for altricial birds' eggs, the eggs of budgerigar, munia, and canary with small pore diameter (0.57 to 1.22 µm) had a lower E. coli penetration rate than pigeon eggs (45.56%, 66.67%, 50%, and 97.78%, respectively, P < 0.05), indicating that pore diameter played a significant role in defending against bacterial trans-shell invasion. We found that eggshell thickness and pore area decreased with egg size. The cuticle quality had no relationship with egg size, but was closely related to the bird species. The E. coli penetration rate of altricial birds' eggs was significantly higher than that of precocial birds' eggs, mainly because the pores are exposed on the eggshell surface and cuticle protection is absent. This study provides detailed information on the eggshell cuticle, which gives insight into the cuticle evolution process that occurred in precocial and altricial bird species. Moreover, the results of E. coli penetration may help understanding the antibacterial behavior in birds.

19.
J Phys Condens Matter ; 31(43): 435301, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31239413

RESUMO

The spin Nernst effect describes a transverse spin current induced by the longitudinal thermal gradient in a system with the spin-orbit coupling. Here we study the spin Nernst effect in a mesoscopic four-terminal cross-bar Weyl semimetal device under a perpendicular magnetic field. Because the spin current is a tensor, it has three elements with the spin direction pointing to the x, y  and z directions when the spin current flows along the transverse lead. By using the tight-binding Hamiltonian combined with the nonequilibrium Green's function method, the three elements of the spin current in the transverse leads and the spin Nernst coefficients are obtained. The results show that the spin Nernst effect in the Weyl semimetal has an essential difference to the traditional Nernst effect: we found that the z direction spin current is zero without the magnetic field while it appears under the magnetic field, and the x and y  direction spin currents in the two transverse leads flow out or in together, in contrast to the traditional spin Nernst effect, in which the spin current is induced by the spin-orbit coupling and flows out from one lead and flows in on the other. We call it the anomalous spin Nernst effect. In addition, we show that the Weyl semimetals have inversion-type symmetry, mirror-reversal-type symmetry and electron-hole-type symmetry, which lead to the spin Nernst coefficients being either odd or even functions of the Fermi energy, the magnetic field and the transverse terminals. Moreover, the spin Nernst effect in the Weyl semimetals are strongly anisotropic and its coefficients are strongly dependent on both the direction of thermal gradient and the direction of the transverse lead connection. Three non-equivalent connection modes (x-z, z-x and x-y  modes) are studied in detail, and the spin Nernst coefficients for three different modes exhibit very different behaviors. These strongly anisotropic behaviors of the spin Nernst effect can be used as the characterization of magnetic Weyl semimetals.

20.
Molecules ; 24(13)2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31248032

RESUMO

Saponins are a class of glycosides whose aglycones can be either triterpenes or helical spirostanes. It is commonly recognized that these active ingredients are widely found in various kinds of advanced plants. Rare saponins, a special type of the saponins class, are able to enhance bidirectional immune regulation and memory, and have anti-lipid oxidation, anticancer, and antifatigue capabilities, but they are infrequent in nature. Moreover, the in vivo absorption rate of saponins is exceedingly low, which restricts their functions. Under such circumstances, the biotransformation of these ingredients from normal saponins-which are not be easily adsorbed by human bodies-is preferred nowadays. This process has multiple advantages, including strong specificity, mild conditions, and fewer byproducts. In this paper, the biotransformation of natural saponins-such as ginsenoside, gypenoside, glycyrrhizin, saikosaponin, dioscin, timosaponin, astragaloside and ardipusilloside-through microorganisms (Aspergillus sp., lactic acid bacteria, bacilli, and intestinal microbes) will be reviewed and prospected.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA