Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.820
Filtrar
1.
Invest Ophthalmol Vis Sci ; 62(3): 1, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33646289

RESUMO

Purpose: Patients with nanophthalmos who undergo intraocular surgery often present with abnormal ciliary zonules. In a previous study, we reported mutation in MYRF that is implicated in the pathogenesis of nanophthalmos. The aim of this study was to model the mutation in mice to explore the role of MYRF on zonule structure and its major molecular composition, including FBN1 and FBN2. Methods: Human MYRF nanophthalmos frameshift mutation was generated in mouse using the CRISPR-Cas9 system. PCR and Sanger sequencing were used for genotype analysis of the mice model. Anterior chamber depth (ACD) was measured using hematoxylin and eosin-stained histology samples. Morphologic analysis of ciliary zonules was carried out using silver staining and immunofluorescence. Transcript and protein expression levels of MYRF, FBN1, and FBN2 in ciliary bodies were quantified using quantitative real-time PCR (qRT-PCR) and Western blot. Results: A nanophthalmos frameshift mutation (c.789delC, p.N264fs) of MYRF in mice showed ocular phenotypes similar to those reported in patients with nanophthalmos. ACD was reduced in MYRF mutant mice (MYRFmut/+) compared with that in littermate control mice (MYRF+/+). In addition, the morphology of ciliary zonules showed reduced zonular fiber density and detectable structural dehiscence of zonular fibers. Furthermore, qRT-PCR analysis and Western blot showed a significant decrease in mRNA expression levels of MYRF, FBN1, and FBN2 in MYRFmut/+ mice. Conclusions: Changes in the structure and major molecular composition of ciliary zonules accompanied with shallowing anterior chamber were detected in MYRFmut/+ mice. Therefore, MYRF mutant mice strain is a useful model for exploring pathogenesis of zonulopathy, which is almost elusive for basic researches due to lack of appropriate animal models.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33620332

RESUMO

Nurses and the nursing profession are the ultimate components of the healthcare system, especially in the operating room, and nurses are exposed to many risks and hazards in the course of performing their jobs. Overall, this appeared to be negligible across the world. Our study aims to give an overview of the risks and safety concerns of operating room nurses as reported in the literature and to look at the strategies or countermeasures that can be taken to surmount them. Major needle and sharps injuries. radiation and surgical smoke exposure, back pain, excessive workloads and patient handling-related injuries were reported extensively. Appropriate precautions, adequate training and experience, enactment of local protocols and policies, creation of a favorable working atmosphere, adequate rest and colleague support can all help overcome these concerns to an extent. At the institutional and political level, effective countermeasures should be taken to guarantee the welfare of competent operators for improved healthcare. Further studies are also required of operating room staff on the risk of chronic diseases and illness in those individuals who have been exposed to atmospheric gasses and smoke.

3.
Diabetes Res Clin Pract ; : 108702, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33609619

RESUMO

AIMS: This research aimed to investigate the effects of high glucose(HG) on the innate immunity of podocytes and diabetic nephropathy (DN) mice via Toll like receptor (TLR) signaling, and explore the protective effectsof human umbilical cord mesenchymal stem cells (HUC-MSCs) on this process. METHODS: HUC-MSCs obtained from human umbilical cord were cocultured with podocytes and transplanted into DN mice. Flow cytometry, CCK-8assay, ELISA, western blot analysis, periodicacid-schiff, masson, immunohistochemistry and immunofluorescence staining was used to detect the inflammation, TLR signaling, physical, biochemical and morphological parameters in podocytes and DN mice. RESULTS: HG reduced the viability of podocytes, activated TLR2 and TLR4 signaling pathway and increased the expression of inflammatory cytokines such as IL-6, IL-1ß, TNF-α, and MCP-1 in podocytes and DN mice. However, HUC-MSCs decreased the inflammation and restrained the TLR signaling pathway caused by HG in vitro and in vivo. Furthermore the rhHGF decreased the expression of TLR2 and TLR4 while the blockade of HGF increased the expression of TLR2 and TLR4 in podocytes. CONCLUSIONS: HUC-MSCs have benefits to the podocytes under HG and the progression of DN by inhibiting TLR signaling pathway and depressing the inflammation. HUC-MSCs may be a therapeutic strategy for treating patients with DN.

4.
Sci Rep ; 11(1): 4652, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33633339

RESUMO

It remains unclear whether leukocyte-related parameters could be used as biomarkers to differentiate metabolically unhealthy overweight/obesity (MUO) from metabolically healthy overweight/obesity (MHO). We aimed to examine the differences in the distribution of leukocyte-related parameters between older adults with MHO and MUO and the correlations of leukocyte-related parameters with individual components of metabolic abnormality. In the Weitang Geriatric Diseases Study on older Chinese adults aged 60 years or above, 404 individuals with MHO and 480 with MUO contributed to the analysis. Overweight/obesity was defined as body mass index (BMI) of 25 kg/m2 or more. MHO and MUO were discriminated based on the Adult Treatment Panel III (ATP III) criteria. Leukocyte-related parameters were assessed using an automated hematology analyzer. All leukocyte-related parameters except monocytes were elevated in MUO group compared with MHO group (all P < 0.05). The prevalence of MUO increased by 24% with each 109/L increase of leukocytes after adjusting for confounders in the multiple-adjusted model (P < 0.01) and each unit elevation of other parameters except lymphocytes and monocytes were significantly associated with the presence of MUO (all P < 0.01). Trend tests revealed a linear trend for the association between MUO and all the leukocyte-related parameters (all P for trend < 0.05). Significant interactions between leukocyte-related parameters and sex on the presence of MUO were observed (all P value for interaction < 0.05). Higher leukocyte-related parameters were found in patients with MUO than those with MHO and were associated with higher prevalence of MUO which seems to be sex-dependent. Further studies are needed to see whether these parameters could be used as biomarkers for the screening or diagnosis for MUO in clinical or public health practice.

5.
Anim Biotechnol ; : 1-19, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33635178

RESUMO

The genetic diversity and population structures of five Chongqing local chicken populations were investigated using by 24 microsatellite markers. Results revealed that the mean number of alleles (NA) ranged from 7.08 (Daninghe chicken, DN) to 8.46 (Nanchuan chicken, NC). The highest observed heterozygosity (HO) and expected heterozygosity (HE) were observed in DN (HO = 0.7252; HE = 0.7409) and the lowest HO and HE were observed in XS (Xiushan native chicken [XS], HO = 0.5910 and HE = 0.6697). The inbreeding coefficient (FIS) within population ranged from 0.022 (DN) to 0.119 (XS). Among the 24 microsatellite markers, four loci (MCW0111, MCW0016, ADL0278, and MCW0104) deviated from the Hardy-Weinberg equilibrium in all the studied populations. The results of population polygenetic analysis based on Nei's genetic distance and STRUCTURE software showed that the clustering of the five populations was incomplete consistent with geographical distribution. Moreover, a large number of gene flows were widespread among different populations, suggesting that genetic material exchanges occurred due to human activities and migration which was also verified by PCoA. In summary, this study preliminarily showed that Chongqing local chicken populations had rich genetic diversity and remarkable genetic divergence, but still high risk in conversion. These findings would be useful to the management of conservation strategies and the utilization of local chicken populations in further.

6.
Neurochem Int ; 144: 104976, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33524473

RESUMO

Blood-brain barrier (BBB) damage at the early stage of ischemic stroke is a vital cause of brain parenchymal injury. The mechanism of BBB disruption has been intensively investigated, but still not fully understood. ß-1, 3-galactosyltransferase 2 (B3galt2) is expressed in the brain, but its role in the pathogenesis of cerebral ischemia remains unknown. In this study, we investigated the role of B3galt2 in cerebral ischemia in mice. Focal cerebral ischemia was induced in mice by middle cerebral artery occlusion (MCAO). B3galt2 protein levels were determined in microvessels which were isolated from ischemic brain at 12, 24 and 72 h after MCAO. Mice were administered lentiviral vectors encoding B3galt2 (LV- B3galt2) or recombinant transforming growth factor-ß1 (r-TGF-ß1) by intracerebroventricular injection. We assessed infarct volume and neurologic deficits on days 1, 3, and 14 after MCAO, blood-brain barrier (BBB) integrity at 12 and 24 h after MCAO, and the levels of TGF-ß1, TGF-ßR(Ⅱ) and p-Smad2/3 at 24 and 72 h after MCAO. Our results indicated that B3galt2 was expressed in brain microvascular endothelial cells and increased in the ischemic microvessels. Overexpression of B3galt2 by LV- B3galt2 administration reduced infarct volume and improved functional outcome after cerebral ischemia. Moreover, the neuroprotective effects were associated with preventing BBB damage. Compared with wild-type (WT) mice, heterozygous B3galt2 knockout (B3galt2-/+) mice not only showed severe BBB damage, neurologic functional deficits, but also showed reduced expression of TGF-ß1, TGF-ßR(Ⅱ) and p-Smad2/3 in microvessels after cerebral ischemia. Pre-administration of r-TGF-ß1 reduced BBB damage, and improved the neurological outcomes in both WT mice and B3galt2-/+ mice after cerebral ischemia. Our results suggested B3galt2 protected against ischemic stroke in mice, and the underlying mechanism might include TGF-ß signaling pathway in brain microvascular endothelial cells.

8.
Adv Mater ; : e2006357, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33624894

RESUMO

Alzheimer's disease (AD) is a common dementia that is currently incurable. The existing treatments can only moderately relieve the symptoms of AD to slow down its progress. How to achieve effective neural regeneration to ameliorate cognitive impairments is a major challenge for current AD treatment. Here, the therapeutic potential of a nanoformulation-mediated neural stem cell (NSC) therapy capable of simultaneous Aß clearance and neural regeneration is investigated in a murine model. Genetically engineered NSCs capable of stably and continuously expressing neprilysin (NEP) are developed to enhance Aß degradation and NSC survival in the brain. A PBAE-PLGA-Ag2 S-RA-siSOX9 (PPAR-siSOX9) nanoformulation with high gene/drug deliverability is synthesized to overcome AD microenvironment-associated adverse effects and to promote neuronal differentiation of the NEP-expressing NSCs. For achieving accurate stereotactic transplantation, Ag2 S quantum-dot-based fluorescence imaging is used to guide NSC transplantation in real time. This strategy shows numerous benefits, including efficient and long-lasting Aß degradation, improved neural regeneration, and accurate cell transplantation. It is shown that a single administration of this therapy achieves long-term efficacy (6 months) with respect to memory reversal and improvement of learning deficits.

9.
Arch Gynecol Obstet ; 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33625596

RESUMO

PURPOSE: Vitamin D (VD) deficiency seems to be associated with the risk of recurrent spontaneous abortion (RSA). Vitamin D receptor (VDR) and cytochrome P450 family 2 subfamily R member 1 (CYP2R1) are two genes which are vital for VD metabolism and actions. However, whether single-nucleotide polymorphisms (SNPs) in these genes are correlated with the risk of RSA are poorly understood. Therefore, we aimed to characterize the relationships among VDR SNPs, CYP2R1 SNPs and RSA. METHODS: This case-control study enrolled 75 RSA patients and 83 controls. Serum VD and some cytokines were detected with LC-MS/MS and flow cytometry, respectively. Genotyping for three SNPs of CYP2R1 (rs10741657, rs10766197 and rs12794714) and five SNPs of VDR (rs7975232, rs1544410, rs2189480, rs2228570 and rs2239179) was done with polymerase chain reaction (PCR) and high-throughput sequencing. All the data were analyzed with appropriate methods and in different models. RESULTS: The results revealed a significant correlation between the AG genotype of CYP2R1 rs12794714 and VD levels (OR 0.686; 95% CI 0.49-0.96; p = 0.028). Besides, the AG and GG genotypes of CYP2R1 rs12794714 were markedly related to the risk of RSA (OR 52.394, 59.497; 95% CI 2.683-1023.265, 3.110-1138.367; p = 0.009, 0.007, respectively). CONCLUSION: Our results indicate that CYP2R1 rs12794714 might be a risk factor for RSA. Hence, early screening of pregnant women for CYP2R1 rs12794714 is necessary to warrant proactive counseling and treatment against RSA.

10.
Biomed Res Int ; 2021: 6637503, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33532491

RESUMO

Background: Chemotherapy is the primary treatment modality used for patients with acute lymphoblastic leukemia (ALL), but inevitably causes microbiota-related oral complications. This study is aimed at investigating the effects of chemotherapy on oral health status, caries risk, and oral microbiome in pediatric patients with ALL. Methods: Thirty-nine children with ALL receiving chemotherapy were enrolled, and a gender-, age-, dentition stage, and socioeconomic class matched healthy counterpart were recruited. Demographic information and overall health condition were obtained through the questionnaire and medical records. Oral examination was performed to assess caries and salivary status, plaque index, and other oral manifestations. Cariogram was used to assess the overall caries risk. Supragingival samples of thirteen ALL subjects and their counterparts were randomly selected to perform a 16S ribosomal RNA gene 454 pyrosequencing. Raw sequence data were screened, trimmed, and filtered using Seqcln and MOTHUR. Results: The prevalence of dental caries, gingivitis, oral mucositis, xerostomia, and candidiasis in ALL groups was higher than that of the control group (p < 0.05). Children with ALL demonstrated higher caries risk compared to healthy controls (HC) based upon Cariogram (p < 0.05). The oral microbial structure of ALL patients receiving chemotherapy is different from that of healthy controls. Oral microbiota of ALL groups showed less alpha diversity and significant differences in the composition of the oral microbiome compared to healthy controls. Conclusions: ALL patients receiving chemotherapy demonstrated compromised oral health, high caries risk, alteration of caries-related factors, and dysbiosis of oral microbiota. These findings may be of clinical importance in developing better strategies for personalized preventive management of oral diseases for pediatric children with ALL.

11.
Neurosci Bull ; 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33559840

RESUMO

Exploring neural markers that predict trust behavior may help us to identify the cognitive process underlying trust decisions and to develop a new approach to promote interpersonal trust. It remains unknown how trust behavior may be predicted early in the decision process. We used electrophysiology to sample the brain activity while participants played the role of trustor in an iterative trust game. The results showed that during the trust generation stage, the trust condition led to higher frontocentral beta band activity related to cognitive inhibition compared to the distrust condition (item level). Moreover, individuals with higher frontocentral beta band activity were more likely to perform trust choices at the single-trial level (individual level). Furthermore, after receiving reciprocity feedback on trialn-1, compared to the betrayal feedback and the distrust choice, the frontocentral beta band oscillation had a stronger predictive effect regarding trust choices on trialn. These findings indicate that beta band oscillations during the decision generation stage contribute to subsequent trust choices.

12.
Plant Dis ; 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33560887

RESUMO

New fungicides are tools to manage fungal diseases and overcome emerging resistance in fugnal pathogens. In this study, a total of 121 isolates of Fusarium fujikuroi, the causal agent of rice bakanae disease (RBD), were collected from various geographical regions of China, and their sensitivity to a novel succinate dehydrogenase inhibitor (SDHI)fungicide 'pydiflumetofen' was evaluated. The 50% effective concentration (EC50) value of pydiflumetofen for mycelial growth suppression ranged from 0.0101 to 0.1012 µg/ml and for conidial germination inhibition ranged from 0.0051to 0.1082 µg/ml. Pydiflumetofen treated hyphae showed contortion and increased branching, cell membrane permeability, and glycerol content significantly. The result of electron microscope transmission indicated that pydiflumetofen damaged the mycelial cell wall and the cell membrane, and almost broken up the cells, which increased the intracellular plasma leakage. There was no cross-resistance between pydiflumetofen and the widely used fungicides such as carbendazim, prochloraz, and phenamacril. Pydiflumetofen was found safe to seeds and rice seedlings of four rice cultivars, used up to 400 µg/ml. Seed treatment significantly decreased the rate of diseased plants in the greenhouse as well as in field trials in 2017 and 2018. Pydiflumetofen showed superb results against RBD, when used at 10 or 20 g a.i./100 kg of treated seeds, providing over 90% control efficacy (the highest control efficacy was up to 97%), which was significantly higher than that of 25% phenamacril (SC) at 10g or carbendazim at 100 g. Pydiflumetofen is highly effective against F. fujikuroi growth and sporulation as well as RBD in the field.

13.
JMIR Ment Health ; 8(2): e24162, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33570500

RESUMO

BACKGROUND: Mental health problems are prevalent among pregnant women, and it is expected that their mental health will worsen during the COVID-19 pandemic. Furthermore, the underutilization of mental health services among pregnant women has been widely documented. OBJECTIVE: We aimed to identify factors that are associated with pregnant women's intentions to seek mental health services. We specifically assessed pregnant women who were at risk of mental health problems in mainland China. METHODS: A web-based survey was conducted from February to March, 2020 among 19,515 pregnant women who were recruited from maternal health care centers across various regions of China. A subsample of 6248 pregnant women with probable depression (ie, those with a score of ≥10 on the 9-item Patient Health Questionnaire) or anxiety (ie, those with a score of ≥5 on the 7-item General Anxiety Disorder Scale) was included in our analysis. RESULTS: More than half (3292/6248, 52.7%) of the participants reported that they did not need mental health services. Furthermore, 28.3% (1770/6248) of participants felt that they needed mental health services, but had no intentions of seeking help, and only 19% (1186/6248) felt that they needed mental health services and had intentions of seek help. The results from our multivariate logistic regression analysis showed that age, education level, and gestational age were factors of not seeking help. However, COVID-19-related lockdowns in participants' cities of residence, social support during the COVID-19 pandemic, and trust in health care providers were protective factors of participants' intentions to seek help from mental health services. CONCLUSIONS: Interventions that promote seeking help for mental health problems among pregnant women should also promote social support from health care providers and trust between pregnant women and their care providers.

14.
BMC Med Imaging ; 21(1): 24, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33573625

RESUMO

BACKGROUND: Coronary CT angiography (CCTA) is a complicated CT exam in comparison to other CT protocols. Exam success highly depends on image assessment of experienced radiologist and the procedure is often time-consuming. This study aims to evaluate feasibility of automatic CCTA reconstruction in 0.25 s rotation time, 16 cm coverage CT scanner with best phase selection and AI-assisted motion correction. METHODS: CCTA exams of 90 patients with heart rates higher than 75 bpm were included in this study. Two image series were reconstructed-one at automatically selected phase and another with additional motion correction. All reconstructions were performed without manual interaction of radiologist. A four-point Likert scale rating system was used to evaluate the image quality of coronary artery segment by two experienced radiologists, according to the 18-segment model. Analysis was done on per-segment basis. RESULTS: Total 1194 out of the 1620 segments were identified for quality evaluation in 90 patients. After automatic best phase selection, 1172 segments (98.3%) were rated as having diagnostic image quality (scores 2-4) and the average score is 3.64 ± 0.55. When motion corrections were applied, diagnostic segment number increases to 1192 (99.8%) and the average score is 3.85 ± 0.37. CONCLUSIONS: With the help of 0.25 s rotation speed, 16-cm z-coverage and AI-assisted motion correction algorithm, CCTA exam reconstruction could be performed with minimum radiologist involvement and still meet image quality requirement.

15.
Sci Rep ; 11(1): 3872, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33594240

RESUMO

Insertion and Deletion (InDel) are common features in genomes and are associated with genetic variation. The whole-genome re-sequencing data from two parents (X1 and X2) of the elite cucumber (Cucumis sativus) hybrid variety Lvmei No.1 was used for genome-wide InDel polymorphisms analysis. Obtained sequence reads were mapped to the genome reference sequence of Chinese fresh market type inbred line '9930' and gaps conforming to InDel were pinpointed. Further, the level of cross-parents polymorphism among five pairs of cucumber breeding parents and their corresponding hybrid varieties were used for evaluating hybrid seeds purity test efficiency of InDel markers. A panel of 48 cucumber breeding lines was utilized for PCR amplification versatility and phylogenetic analysis of these markers. In total, 10,470 candidate InDel markers were identified for X1 and X2. Among these, 385 markers with more than 30 nucleotide difference were arbitrary chosen. These markers were selected for experimental resolvability through electrophoresis on an Agarose gel. Two hundred and eleven (211) accounting for 54.81% of markers could be validated as single and clear polymorphic pattern while 174 (45.19%) showed unclear or monomorphic genetic bands between X1 and X2. Cross-parents polymorphism evaluation recorded 68 (32.23%) of these markers, which were designated as cross-parents transferable (CPT) InDel markers. Interestingly, the marker InDel114 presented experimental transferability between cucumber and melon. A panel of 48 cucumber breeding lines including parents of Lvmei No. 1 subjected to PCR amplification versatility using CPT InDel markers successfully clustered them into fruit and common cucumber varieties based on phylogenetic analysis. It is worth noting that 16 of these markers were predominately associated to enzymatic activities in cucumber. These agarose-based InDel markers could constitute a valuable resource for hybrid seeds purity testing, germplasm classification and marker-assisted breeding in cucumber.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33434612

RESUMO

PURPOSE: To construct and validate a predicting genotype signature for pathologic complete response (pCR) in locally advanced rectal cancer (PGS-LARC) after neoadjuvant chemoradiation. METHODS AND MATERIALS: Whole exome sequencing was performed in 15 LARC tissues. Mutation sites were selected according to the whole exome sequencing data and literature. Target sequencing was performed in a training cohort (n = 202) to build the PGS-LARC model using regression analysis, and internal (n = 76) and external validation cohorts (n = 69) were used for validating the results. Predictive performance of the PGS-LARC model was compared with clinical factors and between subgroups. The PGS-LARC model comprised 15 genes. RESULTS: The area under the curve (AUC) of the PGS model in the training, internal, and external validation cohorts was 0.776 (0.697-0.849), 0.760 (0.644-0.867), and 0.812 (0.690-0.915), respectively, and demonstrated higher AUC, accuracy, sensitivity, and specificity than cT stage, cN stage, carcinoembryonic antigen level, and CA19-9 level for pCR prediction. The predictive performance of the model was superior to clinical factors in all subgroups. For patients with clinical complete response (cCR), the positive prediction value was 94.7%. CONCLUSIONS: The PGS-LARC is a reliable predictive tool for pCR in patients with LARC and might be helpful to enable nonoperative management strategy in those patients who refuse surgery. It has the potential to guide treatment decisions for patients with different probability of tumor regression after neoadjuvant therapy, especially when combining cCR criteria and PGS-LARC.

17.
Brain Res Bull ; 169: 104-111, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33482286

RESUMO

Glycosyltransferases are enzymes that catalyze the formation of a variety of glycoconjugates. Glycoconjugates play vital roles in the nervous system. ß-1, 3-Galactosyltransferase 2 (B3galt2) is one of the major types of glycosyltransferases, which has not been reported in ischemia induced-brain injury. The purpose of this study was to explore the role of B3galt2 exerts and its underlying mechanism in cerebral ischemia in mice. Wild-type (WT) and heterozygous B3galt2 knockout (B3galt2-/+) mice were subjected to 90 min transient focal cerebral ischemia by middle cerebral artery occlusion (MCAO). The brain samples were analyzed at 24 h after reperfusion. The B3galt2 level in the peri-infarct penumbra was quantified. The cerebral infarct volume, neurological deficits, apoptosis and the levels of Reelin and Dab1 were assessed. Compared with control mice, B3galt2-/+ mice not only showed severe brain damage, neurologic functional deficits, but also showed severe neuronal apoptosis in the cortical penumbra after ischemia/reperfusion (I/R). The Caspase-3 activity was increased and the levels of Reelin and Dab1 were decreased in B3galt2-/+ mice. Recombinant human Reelin (rh-Reelin) administered intracerebroventricularly before MCAO significantly reduced infarct volume, and prevented neuronal loss in B3galt2-/+ mice after I/R. Our results suggest B3galt2 deficiency exacerbates ischemic brain damage in acute ischemic stroke in mice, and this was reversed by giving rh-Reelin. B3galt2 might play a beneficial role for neurons survival in the penumbra through modulation of Reelin pathway.

18.
Behav Brain Res ; 402: 113125, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33422597

RESUMO

Age-related cognitive decline is associated with chronic low grade neuroinflammation that may result from a complex interplay among many factors, such as bidirectional communication between the central nervous system (CNS) and gut microbiota. The present study used 2-month-old (young group) and 15-month-old (aged group) male C57BL/6 mice to explore the potential association between age-related cognitive decline and the microbiota-gut-brain axis disorder. We observed that aged mice exhibited significant deficits in learning and memory, neuronal and synaptic function compared with young mice. Aged mice also exhibited significant dysbiosis of the gut microbiota. Disruptions of the intestinal barrier and blood-brain barrier were also observed, including increases in intestinal, low-grade systemic and cerebral inflammation. Furthermore, plasma and brain levels of lipopolysaccharide (LPS) were significantly higher in aged mice compared with young mice, with increasing expression of Toll-like receptor 4 (TLR4) and myeloid differential protein-88 (MyD88) and the nuclear translocation of nuclear factor κB (NF-κB) in intestinal and brain tissues. These findings showed that microbiota-gut-brain axis dysfunction that occurs through LPS-induced activation of the TLR4/NF-κB signaling pathway is implicated in age-related neuroinflammation and cognitive decline.

19.
J Nanosci Nanotechnol ; 21(3): 1672-1677, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33404432

RESUMO

Microfluidic chips made by traditional materials (glass and silicon) are still important for fluorescence tests, biocompatible experiments, and high temperature applications. However, the majority of the present bonding methods suffer from ultra-clean requirement, complicated fabrication process, and low production efficiency. In the present work, an Electrohydrodynamic printing assist bonding method was proposed. By this method, the ultraviolet-cured-glue dots were printed onto the silicon substrate, and then the patterned glass and silicon substrate can be bonded together at room temperature. The influence of printing condition (nozzle inner-diameter, applied voltage, printing height, and flow rate) on the diameter of printed dot was analyzed by experiments. By the optimized printing condition, the glass-silicon microfluidic chip can be well bonded. The bonding strength and leakage test demonstrated the high bonding quality of the microfluidic chip (bonding strength of 28 MPa and leakage pressure of 3.5 MPa).

20.
J Nanosci Nanotechnol ; 21(3): 1735-1741, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33404440

RESUMO

Electrohydrodynamic (EHD) jet printing enables rapid prototyping high-resolution and low-cost lines with width of micrometer or even nanometer. However, EHD printing always suffers from nozzle clogging when the nozzle inner-diameter decrease to micro-scale. Thus fabrication of low cost nozzles becomes significantly important. In this work, 50 µm wide and 12.5 µm deep PMMA (Polymethyl Methacrylate) nozzles were fabricated without using traditional expensive glass capillary pulling approach. To replicate PMMA nozzle with high precision, the embossing condition was optimized according to replication precision, the deformation rate, and maximum stress. To nearly fully bond PMMA nozzle with intact PMMA microchannel, the bonding condition was optimized according the bonding rate and dimension loss of PMMA microchannel. The availability of the fabricated PMMA nozzle was finally verified by EHD printing experiments.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA