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1.
Genes Dev ; 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32115407

RESUMO

Gastrulation in the early postimplantation stage mammalian embryo begins when epiblast cells ingress to form the primitive streak or develop as the embryonic ectoderm. The DNA dioxygenase Tet1 is highly expressed in the epiblast and yet continues to regulate lineage specification during gastrulation when its expression is diminished. Here, we show how Tet1 plays a pivotal role upstream of germ layer lineage bifurcation. During the transition from naive pluripotency to lineage priming, a global reconfiguration redistributes Tet1 from Oct4-cobound promoters to distal regulatory elements at lineage differentiation genes, which are distinct from high-affinity sites engaged by Oct4. An altered chromatin landscape in Tet1-deficient primed epiblast-like cells is associated with enhanced Oct4 expression and binding to Nodal and Wnt target genes, resulting in collaborative signals that enhance mesendodermal and inhibit neuroectodermal gene expression during lineage segregation. A permissive role for Tet1 in neural fate induction involves Zic2-dependent engagement at neural target genes at lineage priming, is dependent on the signaling environment during gastrulation, and impacts neural tube closure after gastrulation. Our findings provide mechanistic information for epigenetic integration of pluripotency and signal-induced differentiation cues.

2.
Nat Commun ; 11(1): 1312, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32161263

RESUMO

The emergence of small open reading frame (sORF)-encoded peptides (SEPs) is rapidly expanding the known proteome at the lower end of the size distribution. Here, we show that the mitochondrial proteome, particularly the respiratory chain, is enriched for small proteins. Using a prediction and validation pipeline for SEPs, we report the discovery of 16 endogenous nuclear encoded, mitochondrial-localized SEPs (mito-SEPs). Through functional prediction, proteomics, metabolomics and metabolic flux modeling, we demonstrate that BRAWNIN, a 71 a.a. peptide encoded by C12orf73, is essential for respiratory chain complex III (CIII) assembly. In human cells, BRAWNIN is induced by the energy-sensing AMPK pathway, and its depletion impairs mitochondrial ATP production. In zebrafish, Brawnin deletion causes complete CIII loss, resulting in severe growth retardation, lactic acidosis and early death. Our findings demonstrate that BRAWNIN is essential for vertebrate oxidative phosphorylation. We propose that mito-SEPs are an untapped resource for essential regulators of oxidative metabolism.

3.
BMC Infect Dis ; 20(1): 224, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171271

RESUMO

BACKGROUND: Cervical lymphadenopathy refers to a frequently observed clinical presentation in numerous pathological conditions. A wide spectrum of diseases can cause cervical lymphadenopathy, irrespective of the fact that the patients are infected with HIV or not. The present study focuses on validating whether the causes of cervical lymphadenopathy differ significantly in HIV and non-HIV patients by using fine-needle aspiration cytology (FNAC) combining cell block. METHODS: A total of 589 patients with cervical lymphadenopathy were recruited in the FNA clinic. The samples were obtained by an auto-vacuumed syringe that benefited the sampling more materials. The cytological smears were prepared by Hematoxylin and Eosin (HE), Periodic Acid Schiff (PAS), Gomori's methenamine silver (GMS) and acid-fast staining. Cell blocks were made if required, and immunohistochemistry stain was performed on the cell block section. RESULTS: The study found 453 (76.9%) patients with HIV and 136 (23.1%) patients without HIV infection. The average age of HIV-infected patients was 34.8 ± 10.2 years, which was significantly lower than that of non-HIV-infected patients (42.9 ± 18.1 years) (p < 0.01). Of all patients infected with HIV, 390 (86.1%) were males. This proportion was significantly higher than that of non-HIV-infected patients [65/136 (47.8%)] (p < 0.01). The major causes of cervical lymphadenopathy in HIV positive patients were mycobacterial infection (38.4%), reactive hyperplasia (28.9%), non-specific inflammation (19.9%), and malignant lesions (4.2%). In contrast, the most common causes in HIV negative patients were reactive hyperplasia (37.5%), malignancy (20.6%), non-specific inflammation (19.1%) and mycobacterial infection (12.5%). Opportunistic infections such as non-tuberculous mycobacteria (4.2%), cryptococcosis (1.5%), Talaromyces marneffei (1.5%) and other fungi (0.4%) were found only in HIV-infected individuals. Non-Hodgkin's lymphoma (2.4%) was the most common malignant lesion in patients with HIV infection, followed by Kaposi's sarcoma (0.9%) and metastatic squamous cell carcinomas (0.7%). However, the most common malignancy in non-HIV-infected patients was metastatic carcinomas (14%) including small cell carcinomas, adenocarcinomas, squamous cell carcinomas and hepatocellular carcinoma, which were noticeably greater than the HIV patients (p < 0.01). CONCLUSIONS: There were significantly different causes of cervical lymphadenopathy in HIV infected and non-HIV infected patients. FNAC was a useful diagnostic method for differential diagnosis of cervical lymphadenopathy.

4.
J Infect Dis ; 221(Supplement_2): S279-S287, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32176792

RESUMO

BACKGROUND: This prospective study compared pharmacokinetics (PK) and pharmacodynamics (PD) of linezolid in patients with sepsis receiving continuous venovenous hemofiltration (CVVH) with patients receiving extended daily hemofiltration (EDH). METHODS: Patients with sepsis treated with linezolid and CVVH or EDH were included. Serial blood samples were collected and linezolid concentrations measured. PKs were analyzed using Pmetrics. Monte Carlo simulations were used to evaluate PD target achievement. RESULTS: From 20 patients, 320 blood samples were collected for PK and PD analysis. PK profiles of linezolid were best described by a 2-compartment model. PK parameters were not significantly different between EDH and CVVH groups and were associated with body weight, renal replacement therapy (RRT) duration, and sequential organ failure assessment score. Monte Carlo simulations showed poor fractional target attainment for a minimum inhibitory concentration (MIC) of 2 mg/L with standard 600 mg intravenous administration every 12 hours. CONCLUSIONS: Patients with sepsis receiving RRT exhibited variability in PK/PD parameters for linezolid. PK parameters were not significantly different between CVVH- and EDH-treated patients. Higher probability of target attainment would be achievable at a MIC of 2 mg/L in EDH patients. Higher linezolid doses should be considered for patients on RRT to achieve adequate blood levels.

7.
Microb Pathog ; : 104126, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32173494

RESUMO

Streptococcus pneumoniae (pneumococcus) is touted to be the generally found pathogen in patients with respiratory issues and there is an epidemiologic linkage present between Respiratory syncytial virus (RSV). This study aim at investigating the interaction between RSV and two serotypes of S. pneumoniae using a distinct animal model and a well-established colonizing pneumococcal strain. Phase variants phenotype of each strain was determined under oblique light. Co infection model was developed using BALB/c mice housed in a BSL-2 facility. Coinfection experiments were performed and number of bacterial colonies was quantified and phase determination was evaluated. RSV was detected in sample through real-time quantitative PCR. Adherence assays were performed to determine adherence of Spn strains and its knock out ΔNanA to nasopharyngeal carcinoma (NPC) epithelial CNE3 cell line. The biofilm viability was determined and phase composition was counted using plate count. Neuraminidase activity was measured in fluorometircassessed using 2'-(4-methylumbelliferyl)-α-D-N-acetylneuraminic acid (MUAN) as substrate as described in earlier literature. The GraphPad Software version 5.01 i.e., GraphPad Prism was used to conduct the statistical analysis. The extent of bacterial colonization was increased significantly (p<0.05), when the mice were co infected. Nasal epithelium remained intact in mock sample with features of a thick mucociliary border. A small percentage of pneumococci exhibit phase variation between opaque phase and transparent phase. The percentage adherent of both phase were not found to be varying significantly within serotype but it was seen that nonpathogenic type 27 was more adherent. Biofilm formation was selectively more for transparent phase from a mixed-phase inoculum. Adherence of both phase variant of S. pneumoniae to nasopharyngeal epithelial cells two hours post infection expressed as the percentage of adherent bacteria relative to the inoculum. In absence of viral infection, the nasal colonization of the opaque and the transparent variant was increased many folds, which was a significant differences. The extent of nasal colonization by the ΔNanA mutant strain were significantly reduced post-bacterial infection for both type of wild-type (P <0.05). The findings explore insights into the interactions occurring between S. pneumoniae and RSV during respiratory infections and pneumococcal acquisition, indicate that pneumococcal serotypes have different ability to cause infection as well as co infections and potentially follow an unappreciated mechanism. Much more research work is needed to further understand the minutiae of this interaction within co-infection process.

8.
Molecules ; 25(5)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32110995

RESUMO

We investigated the potential ability of quercetin to protect against lipopolysaccharide (LPS)-induced intestinal oxidative stress in broiler chickens and the potential role of the Nrf2 (nuclear factor erythroid 2-related factor 2) signaling pathway. One-day-old broiler chickens (n = 240) were randomized into four groups: saline-challenged broiler chickens fed a basal diet (Con), LPS-challenged broiler chickens on a basal diet (LPS), and LPS-treated broiler chickens on a basal diet containing either 200 or 500 mg/kg of quercetin (Que200+LPS or Que500+LPS). Quercetin (200 mg/kg) significantly alleviated LPS-induced decreased duodenal, jejunal, and illeal villus height and increased the crypt depth in these regions. Quercetin significantly inhibited LPS-induced jejunal oxidative stress, including downregulated reactive oxygen species (ROS), malondialdehyde (MDA), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels, and it upregulated superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels. Quercetin relieved LPS-induced jejunal mitochondria damage and upregulated mitochondrial DNA copy number-related gene expression, including cytochrome c oxidase subunit 1 (COX1), ATP synthase F0 subunit 6 (ATP6), and NADH dehydrogenase subunit 1 (ND1). Quercetin attenuated the LPS-induced inhibition of Nrf2 activation, translocation, and downstream gene expression, including heme oxygenase-1 (HO-1), NAD (P) H dehydrogenase quinone 1 (NQO1), and manganese superoxide dismutase (SOD2). Additionally, quercetin attenuated the LPS-inhibition of c-Jun N-terminal kinase (JNK), Extracellular Regulated protein Kinases (ERK), and p38MAPK (p38) phosphorylation in the MAPK pathway. Thus, quercetin attenuated LPS-induced oxidative stress in the intestines of broiler chickens via the MAPK/Nrf2 signaling pathway.

9.
Opt Express ; 28(1): 753-759, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118997

RESUMO

A magnetic mirror operating in the terahertz band is designed based on the functional reflective metasurface, which is simply constructed by a one-dimensional periodic lithium tantalate micro cylindrical rod array on a Teflon substrate coated with a metal layer at the bottom and reflects the incoming electric field with a zero-phase change. Magnetic dipole resonance of the micro cylindrical rods excited in the metasurface is attributed to the perfect magnetic mirror at the frequency of 0.286 THz with the reflectivity of R = 0.98 for a normal incident electromagnetic wave. By real-time varying the direction from normal (0) to 28.45 degrees and the frequency from 0.286 to 0.382 THz of the incident wave, the metasurface can still behave as a perfect magnetic mirror with the reflectivity as high as 0.99. Most interestingly, in this case, the metasurface possesses the property of a retroreflector that the reflected wave returns along the direction of the incident wave, which is consistent with the grating equation. The tunable perfect magnetic mirror effect and the retroreflector property may provide ways in novel photonic devices and sensing applications.

10.
Hum Genet ; 139(4): 521-530, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32002660

RESUMO

Newborn hearing screening is not designed to detect delayed-onset prelingual hearing loss or aminoglycoside-antibiotic-induced ototoxicity. Cases with severe to profound hearing loss have been reported to have been missed by newborn hearing screens. The aim of this study was to evaluate the efficacy of concurrent hearing and genetic screening in the general population and demonstrate its benefits in practice. Enrolled newborns received concurrent hearing and genetic screens between September 1, 2015 and January 31, 2018. Of the 239,636 eligible infants (median age, 19 months), 548 (0.23%) had prelingual hearing loss. Genetic screening identified 14 hearing loss patients with positive genotypes and 27 patients with inconclusive genotypes who had passed the hearing screens. In addition, the genetic screen identified 0.23% (570/239,636) of the newborns and their family members as at-risk for ototoxicity, which is undetectable by hearing screens. In conclusion, genetic screening complements newborn hearing screening by improving the detection of infants at risk of hereditary hearing loss and ototoxicity, and by informing genotype-based clinical management for affected infants and their family members. Our findings suggest that the practice should be further validated in other populations and rigorous cost-effectiveness analyses are warranted.


Assuntos
Testes Genéticos , Perda Auditiva , Triagem Neonatal , Feminino , Perda Auditiva/diagnóstico , Perda Auditiva/genética , Testes Auditivos , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos
11.
Biol Open ; 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32001490

RESUMO

For robot-assisted rehabilitation and assessment of the patients with motor dysfunction, the parametric generation of their normal gait as the input for the robot is essential to match with the features of the patient to a greater extent. In addition, the gait needs to be in three-dimensional space, which meets the physiological structure of the human better, rather than only in sagittal plane. Thus, a method for the parametric generation of three-dimensional gait based on the influence of the motion parameters (MPs) and structure parameters (SPs) is presented. First, the three-dimensional gait kinematic of participants is collected, and trajectories of ankle joint angle and ankle center position are calculated. Second, for the trajectories, the gait features are extracted including gait events indicating the physiological features of the walking gait in additional to extremes indicating the geometrical features of the trajectories. Third, regression models are derived after using leave-one-out cross-validation for model optimization. Finally, cubic splines are fitted between the predicted gait features to generate the trajectories for a full gait cycle. It is inferred the generated curves well match the measured curves. The method presented herein will gives an important reference for the research of the lower limb rehabilitation robots.

12.
J Agric Food Chem ; 68(11): 3585-3593, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32096634

RESUMO

Glutenin macropolymer (GMP) plays a pivotal role in improving dough quality. In this study, a novel Lactobacillus plantarum LB-1 (LB-1) on the fermentation characteristics of dough were investigated from the perspective of GMP. The results showed that the ordered secondary structure (α-helices and ß-sheets) content of GMP in dough synergistically fermented by yeast and LB-1 (DYLB-1) was 20.5% more than that in dough fermented by yeast (DY), and the average particle size was 2.46 µm smaller. Moreover, the higher level of total free amino acids and lower free sulfhydryl group (SHf) content in the DYLB-1 indicated that the network structure strength was enhanced. Furthermore, the protein and starch in the DYLB-1 were uniformly and closely connected, which endows the DYLB-1 with excellent rheological and gas production properties. Therefore, the method used to produce the DYLB-1 was recommended as a new strategy for producing high-quality dough.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32004636

RESUMO

BACKGROUND: OLZ/SAM is a combination of olanzapine, an atypical antipsychotic, and samidorphan, an opioid antagonist, and is in development for the treatment of schizophrenia and bipolar I disorder. OLZ/SAM is under development with the intent to provide the established antipsychotic efficacy of olanzapine while mitigating olanzapine-associated weight gain. This thorough QT study assessed the effects of therapeutic and supratherapeutic doses of OLZ/SAM on cardiac repolarization in patients with schizophrenia. METHODS: In this randomized, double-blind, placebo- and positive (moxifloxacin)-controlled, parallel-group study, 100 patients aged 18 to 60 years with stable schizophrenia were randomized 3:2 to the active arm and control arm. Subjects in the active arm received a therapeutic dose of 10/10 mg (10 mg olanzapine/10 mg samidorphan) on days 2-4, 20/20 mg on days 5-8, and a supratherapeutic dose of 30/30 mg (1.5 times and 3 times the maximum recommended daily dose of olanzapine and samidorphan, respectively) on days 9-13, and moxifloxacin-matched placebo on days 1 and 14. Subjects in the control arm received a single oral dose of moxifloxacin 400 mg and moxifloxacin-matched placebo on days 1 and 14 in a nested crossover fashion, along with OLZ/SAM-matched placebo on days 2-13. Serial electrocardiograms (ECGs) and simultaneous plasma drug concentrations were determined pre- and post-dose. The effects of OLZ/SAM on heart rate and ECG parameters (QT interval with Fridericia's correction [QTcF], PR and QRS interval, and T-wave morphology) were evaluated, and the primary endpoint was change from baseline in QTcF (ΔQTcF). The relationship between drug concentration and ΔQTcF (C-QTc) was evaluated using a linear mixed-effects model. Safety monitoring included adverse events reporting and clinical laboratory assessments. RESULTS: Based on primary analysis using C-QTc modeling, no clinically concerning QTc effect (ie, placebo-corrected ΔQTcF [ΔΔQTcF] ≥10 msec) was observed across the OLZ/SAM dose range tested (10/10 to 30/30 mg), up to olanzapine and samidorphan concentrations of approximately 110 and 160 ng/mL, respectively. The slope (90% confidence interval [CI]) of the C-QTc relationship was shallow and not significant for either olanzapine or samidorphan (0.03 [-0.01, 0.08] and 0.01 [-0.01, 0.04] msec per ng/mL, respectively). The predicted ΔΔQTcF (90% CI) was 2.33 (-2.72, 7.38) and 1.38 (-3.37, 6.12) msec at the observed geometric mean maximal concentration (Cmax) of olanzapine (62.6 ng/mL) and samidorphan (75.1 ng/mL) on day 13, respectively. The study's assay sensitivity was confirmed by the C-QTc relationship of moxifloxacin. OLZ/SAM was well tolerated at all doses; adverse events occurring in >5% of subjects treated with OLZ/SAM were somnolence, weight increased, nausea, and dizziness. CONCLUSIONS: This thorough QT study in patients with stable schizophrenia demonstrated that OLZ/SAM, in doses and plasma concentrations up to supratherapeutic levels, does not have a clinically relevant effect on ECG parameters, including QT/QTc prolongation.

14.
Pflugers Arch ; 472(2): 245-258, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32006095

RESUMO

High-intensity interval training (HIIT) is a time-efficient alternative to moderate-intensity continuous training (MICT) to improve metabolic health in older individuals. However, differences in adipose tissue metabolism between these two approaches are unclear. Here, we evaluated the effects of HIIT and MICT on metabolic phenotypes in aged rats. HIIT significantly decreased fat mass, increased percent lean mass, decreased fat-to-lean ratio, reduced serum high-sensitivity C-reactive protein, increased serum interleukin-10 levels, and decreased perirenal adipose tissue leptin compared with rats in the sedentary (SED) group. HIIT also increased pregnenolone, cortisol, and corticosterone in both adipose tissue and serum. Both exercise modalities enhanced hormone-sensitive lipase and adipose triglyceride lipase expression compared with the SED group and decreased palmitic acid, stearic acid, octadecadienoic acid, urea, 1-heptadecanol, and α-tocopherol. MICT was related to glycerolipid metabolism, whereas HIIT was related to steroid hormone biosynthesis. Overall, HIIT showed more favorable regulation of anti-inflammatory activity than MICT.

15.
Biomaterials ; 236: 119803, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32028170

RESUMO

Nanobubbles, as a kind of new ultrasound contrast agent (UCAs), have shown promise to penetrate tumor vasculature to allow for targeted imaging. However, their inherent physical instability is an ongoing concern that could weaken their imaging ability with ultrasound. Gas vesicles (GVs), which are genetically encoded, naturally stable nanostructures, have been developed as the first ultrasonic biomolecular reporters which showed strong contrast enhancement. However, further development of tumor imaging with GVs is limited by the quick clearance of GVs by the reticuloendothelial system (RES). Here, we developed PEGylated HA-GVs (PH-GVs) for in-tumor molecular ultrasound imaging by integrating polyethylene glycol (PEG) and hyaluronic acid (HA) in GV shells. PH-GVs were observed to accumulate around CD44-positive cells (SCC7) but not be internalized by macrophage cell line RAW 264.7. Green fluorescence from PH-GVs was found around cell nuclei in the tumor site after 6 h and the signal was sustained over 48 h following tail injection, demonstrating PH-GVs' ability to escape the clearance from the RES and to penetrate tumor vasculature through enhanced permeability and retention (EPR) effects. Further, PH-GVs produced strong ultrasound contrast in the tumor site in vivo, with no obvious side-effects detected following intravenous injection. Thus, we demonstrate the potential of PH-GVs as novel, nanosized and targeted UCAs for efficient and specific molecular tumor imaging, paving the way for the application of GVs in precise and personalized medicine.

16.
Sheng Wu Gong Cheng Xue Bao ; 36(1): 109-121, 2020 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-32072786

RESUMO

The CRISPR/Cas9 gene editing technology directs Cas9 protein to recognize, bind and cleave the target site specifically by using artificial single-guide RNA (sgRNA), through non-homologous end joining or homologous end-recombinant repair mechanisms of cells, which can be engineered to knockout or knock-in of genomes. RIG-I is a pattern recognition receptor that recognizes the 5'-triphosphate-containing RNA in the cytoplasm and activates IRF3/7 and NF-κB by interacting with the downstream signaling molecule MAVS, thus initiating the expression of type I interferons and inflammatory factors. Previous studies found that influenza B virus (IBV) can up-regulate the expression of RIG-I. In the present study, to explore whether RIG-I is the major receptor for IBV to active the antiviral innate immune response and its effect on IBV replication, RIG-I gene in 293T cells was knocked out by CRISPR-Cas9 system, and a stable RIG-I knockout 293T (RIG-I(-/-) 293T) cell line was screened by puromycin pressure. The results of Western blotting showed that RIG-I was not expressed in this cell line after IBV or Sendai virus (SeV) infection, indicating that the RIG-I(-/-) 293T cell line was successfully constructed. The transcription levels of interferons, inflammatory factors and interferon-stimulated genes in RIG-I(-/-) 293T cells which were infected by IBV decreased significantly compared with those in wild-type 293T cells. Moreover, the phosphorylation of p65 and IRF3 were not detected in IBV or SeV infected RIG-I(-/-) 293T cells. It is indicated that the expression of cytokines mainly depends on the RIG-I-mediated signaling pathway at the early stage of IBV infection. Furthermore, the multi-step growth curves of IBV in the wild type and RIG-I(-/-) 293T cells showed that RIG-I inhibited the replication of IBV. Collectively, the RIG-I knockout 293T cell line was successfully constructed. We found that RIG-I is the main receptor for IBV to active the antiviral innate immune response and is critical for inhibiting IBV replication, which lays the foundation for further study of IBV infection mechanism.


Assuntos
Vírus da Influenza B , Proteína DEAD-box 58 , Células HEK293 , Humanos , Imunidade Inata , Interferons , Replicação Viral
17.
Artigo em Inglês | MEDLINE | ID: mdl-32100373

RESUMO

Information about the effects of photoperiod on the testicular transcriptome of broiler roosters is limited. The aim of the present study was to explore the effect of different photoperiodic regimes on gene expression in the testes of broiler breeder roosters. One hundred and twenty Arbor Acres broiler breeder roosters aged 20 weeks were assigned to one of three groups (n = 40) and subjected to different photoperiodic regimes: control (CTR; 12.5 L:11.5 D), short day (SD; 8 L:16 D) and long day (LD; 16 L:8 D). After 4 weeks, the testes of 10 randomly selected birds from each group were dissected, sliced and haematoxylin-eosin stained. The testicular transcriptome of roosters from the SD and LD groups was determined by RNA sequencing (RNA-Seq), and the results were confirmed using quantitative real-time PCR. The seminiferous tubule area and sperm count increased significantly with the prolongation of photoperiod (p < .01). Additionally, the RNA-Seq results indicated that 387 genes were upregulated and 1,052 genes were downregulated in the LD group compared with those in the SD group. Several crucial genes involved in rooster testicular development and reproduction were also screened, including heat shock proteins 90, extracellular regulated protein kinases 1, phosphatidylinositol 3-kinase, adenosine 5'-monophosphate -activated protein kinase, BCL-6 and Smad3. The differentially expressed genes were enriched in the mammalian targets of rapamycin (mTOR), forkhead box (FoxO), transforming growth factor beta (TGF-ß) and insulin signalling pathway. In conclusion, a 16 hr photoperiod for 4 weeks increased the seminiferous tubule duct area and promoted spermatogenesis in the rooster's testicles, and the mTOR, FoxO, TGF-ß and insulin signalling pathways may be involved.

18.
J Orthop Surg Res ; 15(1): 45, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046746

RESUMO

BACKGROUND: Current there are different screws fixation methods used for fixation of the talar neck fracture. However, the best method of screws internal fixation is still controversial. Few relevant studies have focused on this issue, especially by finite element analysis. The purpose of this study was to explore the mechanical stability of dual screws internal fixation methods with different approaches and the best biomechanical environment of the fracture section, so as to provide reliable mechanical evidence for the selection of clinical internal fixation. METHODS: The computed tomography (CT) image of the healthy adult male ankle joint was used for three-dimensional reconstruction of the ankle model. Talus neck fracture and screws were constructed by computer-aided design (CAD). Then, 3D model of talar neck fracture which fixed with antero-posterior (AP) parallel dual screws, antero-posterior (AP) cross dual screws, postero-anterior (PA) parallel dual screws, and postero-anterior (PA) cross dual screws were simulated. Finally, under the condition of 2400N vertical load, finite element analysis (FEA) were carried out to compare the outcome of the four different internal fixation methods. The results of Von Mises stress, displacement of four groups which contain talus fracture fragments and screws internal fixations were analyzed. RESULTS: Compared with the other three groups, postero-anterior (PA) parallel dual screws had better results in the stress peak, stress distribution, and displacement of talus and internal fixation. CONCLUSIONS: To sum up, the Von Mises stress of fracture section was the smallest, the stress distribution of screws were the most scattered, and the peak value was the smallest in posterior to anterior parallel double screws fixation, which was obviously better than that in the other three groups. When using screws internal fixation, the method of posterior to anterior screws fixation is better than that of anterior to posterior screws fixation, and the peak value and stress distribution of parallel double screws fixation is better than that of cross double screws fixation. Thus, for the talar neck fracture, the use of posterior to anterior parallel double screws fixation is recommended in clinical surgery.

19.
Appl Microbiol Biotechnol ; 104(7): 2947-2955, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32055911

RESUMO

The anodized titanium nanotubes (TiO2-NTs) are considered to be a potential material in clinical therapy. To enhance the antibacterial property of TiO2-NTs, cefuroxime is introduced into TiO2-NTs, and then, different chitosan layers are coated to control the release of cefuroxime. SEM and FTIR are adapted for the characterization of prepared TiO2-NTs. The effects of chitosan coating thickness on release of cefuroxime are also investigated, followed with the antibacterial property evaluation. The results show TiO2-NTs are fabricated by anodization method and cefuroxime is also successfully loaded into the nanotubes. The thickness of chitosan coating is an important factor to the release rate of cefuroxime. Antimicrobial detection and morphology observation of S. aureus show a sustained 7-day drug release and strong negative effect on bacteria. The approach in this study provides a broadly applicable method to fabricate titanium-based orthopedic implants with enhanced antibacterial properties.

20.
Sci Rep ; 10(1): 3133, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32081949

RESUMO

In the central nervous system (CNS), γ-aminobutyric acid A (GABAA) receptors mediate two types of inhibitory effects. Phasic inhibition involves the activation of synaptic GABAA receptors, and tonic inhibition is mediated by extrasynaptic GABAA receptors. GABAA receptors are important regulators of neuronal activity and are involved in a range of neurological disorders. In this study, we conducted sIPSCs recordings on hippocampal CA1 pyramidal neurons in WT SD rats and found that exposure to blue light could specifically block the tonic inhibition and sIPSCs, and regulate neuronal activity. These observations indicate the existence of a non-opsin photosensitive pathway that regulates the GABA inhibitory system in the CNS.

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