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Int J Biol Macromol ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31493451


Human papilloma virus (HPV) affects predominantly the genital area, which includes vagina, cervix, penis, vulva scrotum, rectum and anus. Among 100 types of HPV, 14 types are considered to cause the risky cancer. The gene HPV-16 E7 is responsible for the development of cancer with the infected women. Earlier identification of this gene sequence avoids the cancer progression. The targeted HPV-16 E7 sequence was sandwiched by capture and reporter sequences on the carbodiimidazole-modified interdigitated electrode (IDE) surface. Target sequence at 100 fM was paired to the capture sequence immobilized on IDE sensing surface. To this surface, different concentrations of reporter sequence with and without gold rod (GNR) were evaluated. In both cases the detections were attained 1 aM by the reporter sequence pairing and with GNR increments in current were found. This enhancement was found to be 1000 folds, considering the condition was revealed in the absence of reporter. This sandwich detection strategy of capture-target-reporter sequences for HPV-16 detection on the IDE sensing surface helps to diagnose the association of cervical cancer.

J Leukoc Biol ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31483071


The percentage of human CD56- CD16+ NK cells increases during chronic infection with human HIV; however, the biologic role of CD56- CD16+ NK cells in HIV infection is unclear. Our results demonstrate that the percentage of CD56- CD16+ NK cells producing IL-10 and TGF-ß was higher than CD56dim CD16+ NK cells. CD56- CD16+ NK cells could inhibit IFN-γ production by autologous CD8+ T cells, and this inhibition could be partially reversed by anti-IL-10, anti-TGF-ß, or anti-PD-L1 mAbs. CD56- CD16+ NK cells are potential targets for the development of novel immune therapies against HIV infection.

J Agric Food Chem ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31507180


Mastitis, inflammation of the mammary gland, occurs in both humans and animals. Staphylococcus aureus (S. aureus) is the most common infectious bacterial pathogen associated with mastitis. We investigated the effects of allicin on S. aureus-induced mastitis in mice. Pathological histology revealed that allicin inhibited S. aureus-induced pathological damage and myeloperoxidase activity in mammary tissues. Enzyme-linked immunosorbent assays demonstrated that allicin reduced the production of IL-1ß and TNF-α as well as inhibited NF-κB and MAPKs pathway by reducing phosphorylation of p65, IκBα, p38, JNK and ERK. Western blotting revealed that allicin reduced TLR2 or TLR6 expression in mammary tissues and cells, but not in HEK293 cells. The lipid raft content was reduced by allicin, which inhibited signaling downstream of TLR2 and TLR6. Liver X receptor alpha (LXRα) luciferase reporter assays and LXRα interference experiments showed that allicin improved LXRα activity and ATP-binding cassette G and A1 (ABCG, ABCA1) expression, thereby reducing cholesterol levels, lipid raft formation and downstream TLR2 and TLR6 pathway activity. These results demonstrated that allicin exerted anti-inflammatory effects against S. aureus mastitis by improving LXRα activity and reducing lipid raft formation.

CNS Neurosci Ther ; 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31503421


Alzheimer's disease (AD) is characterized by ß-amyloid (Aß) deposition and Tau phosphorylation, in which its pathogenesis has not been cleared so far. The metabolism of Aß and Tau is critically affected by the autophagy. Abnormal autophagy is thought to be involved in the pathogenesis of AD, regulating autophagy may become a new strategy for AD treatment. In the early stage of AD, the presence of Aß and Tau can induce autophagy to promote their clearance by means of mTOR-dependent and independent manners. As AD progress, the autophagy goes aberrant. As a result, Aß and Tau generate continually, which aggravates both autophagy dysfunction and AD. Besides, several related genes and proteins of AD can also adapt autophagy to make an effect on the AD development. There seems to be a bi-directional relationship between AD pathology and autophagy. At present, this article reviews this relationship from these aspects: (a) the signaling pathways of regulating autophagy; (b) the relationships between the autophagy and the processing of Aß; (c) Aß and Tau cause autophagy dysfunction; (d) normal autophagy promotes the clearance of Aß and Tau; (e) the relationships between the autophagy and both genes and proteins related to AD: TFEB, miRNAs, Beclin-1, Presenilin, and Nrf2; and (f) the small molecules regulating autophagy on AD therapy. All of the above may help to further elucidate the pathogenesis of AD and provide a theoretical basis for clinical treatment of AD.

J Gastrointestin Liver Dis ; 28(3): 289-296, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31517325


BACKGROUND AND AIMS: Liver fibrosis is stage-dependently associated with non-alcoholic fatty liver disease (NAFLD) progression. The increased awareness of non-invasive diagnosis has led to the establishment of many fibrosis diagnosis models with various accuracies. We aimed to evaluate the diagnostic performance of nine clinical non-invasive fibrosis models in NAFLD and provide an optimal diagnostic method for advanced fibrosis by step layered combination of non-invasive models. METHODS: 453 consecutive patients with biopsy-proven NAFLD were enrolled from three centers and were divided into study cohort and validation cohort randomly. Aspartate aminotransferase-to-platelet ratio index (APRI), BARD, FiB-4, FibroMeter NAFLD, Forns' Index, Hui model, non-invasive Koeln-Essen- index (NIKEI), S Index and NAFLD fibrosis score (NFS) were calculated. The high area under the receiver operating characteristic curve (AUROC) models were stepwise combined for further diagnosing NAFLD advanced fibrosis. RESULTS: All models had good performance with high negative predictive value (NPV) and specificity for diagnosing fibrosis, while positive predictive value (PPV) and sensitivity were low. APRI, BARD, FibroMeter NAFLD and NIKEI had higher AUROCs and their step layered combination for diagnosing advanced fibrosis showed high specificity, sensitivity, NPV and PPV up to 89.13%, 72.50%, 74.36%, and 88.17%, which also performed well in the validation cohort. CONCLUSIONS: APRI, BARD, FibroMeter NAFLD and NIKEI had better diagnostic accuracy, and could be preferred for diagnosing NAFLD fibrosis. The step layered combination of these models performed much better than each single scoring system for diagnosing advanced fibrosis, provides valuable reference for clinical practice and might be a potential substitution of liver biopsy.

J Vestib Res ; 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31450524


BACKGROUND: The activities and participation component of the International Classification of Functioning, Disability and Health (ICF) has gained increasing recognition in rehabilitation field. The vestibular activities and participation measure (VAP) was the first instrument using the ICF to evaluate activities and participation outcomes for vestibular research and clinical practice. OBJECTIVES: This study aimed to cross-culturally adapt the VAP into Chinese language and to examine the psychometric properties of the Chinese version of VAP (VAP-C). METHODS: A standard "forward-backward" translation procedure was followed and the results were presented to the panel of experts and consensus was sought. Internal consistency was assessed using Cronbach's alpha and test-retest reliability examined by intraclass correlation coefficient (ICC). Convergent validity was determined by calculating the Pearson's correlation coefficient between the VAP-C and the Visual Analog Scale (VAS) and the Dizziness Handicap Inventory (DHI). Discriminative validity for test subjects versus control subjects was evaluated by Receiver Operating Characteristic curve (ROC) analysis. RESULTS: Minor revisions were made during translation to ensure semantic equivalence and to suit Chinese culture. A total of 121 patients complaining of dizziness or vertigo due to peripheral vestibular disorders (test subjects) and 41 control subjects were enrolled. Cronbach's alpha was 0.94 for the VAP-C total scale and greater than 0.80 for the two subscales. ICC for the VAP-C total scale was 0.78, and for subscale one was 0.77 and subscale two 0.76. The VAP-C had strong correlations (r = 0.85-0.88) with the VAS and fair to moderate correlations (r = 0.23-0.53) with DHI. Through ROC analysis, we found the VAP-C discriminated significantly between patients and control subjects. Based on the estimate of Youden J, the optimal cut-off values for VAP-C total and the two subscales were established. CONCLUSIONS: The VAP-C shows evidence of reliability and validity, which can be applied for evaluating the impact of the vestibular disorder on patients' activities and participation in Chinese language populations.

BMC Infect Dis ; 19(1): 726, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31420059


BACKGROUND: Nucleic acid amplification tests (NAAT) have been used as a diagnostic tool for pulmonary tuberculosis (PTB) in Taiwan for many years. In accordance with Taiwanese legislation, health care personnel are required to notify the Centers for Disease Control and Prevention (CDC) in case of suspected PTB. This study aimed to investigate the impact of NAAT(Gen-Probe) on the notification system for PTB and anti-tuberculosis treatments in Taiwan. METHODS: A retrospective study on the impact of NAAT (Enhanced Amplified Mycobacterium tuberculosis Direct Test [E-MTD], Gen-Probe, San Diego, CA, USA) [NAAT(Gen-Probe)] was carried out at Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation from March 2011 to December 2017. During the study period, microscopic acid-fast-bacilli smears and mycobacterial cultures were available for PTB diagnosis. NAAT(Gen-Probe) was first introduced at the hospital in January 2014 for use as a diagnostic method for PTB. Positive sputum culture was considered as the gold standard for PTB diagnosis. We excluded clinically-diagnosed PTB cases. RESULTS: When NAAT(Gen-Probe) was applied, the rate of error notification to CDC decreased from 64.3 to 7.0% (P < 0.001), and unnecessary anti-TB treatments administered to suspected cases decreased from 14.9 to 6.5% (P = 0.005). In the non-PTB group, the mean duration of unnecessary anti-TB treatments changed from 38.9 ± 38.3 days to 37.0 ± 37.9 days (P = 0.874). In the PTB group, the mean time from notifying CDC to initiating treatment decreased from 3.05 ± 6.95 days to 1.48 ± 1.99 days (P = 0.004). The sensitivity, specificity, positive predictive value, and negative predictive value of NAAT(Gen-Probe) were 99.0, 92.3, 99.0, and 92.3%, respectively. CONCLUSIONS: Use of NAAT(Gen-Probe) led to decrease in the rate of error notification of suspected PTB cases to the CDC, avoidance of unnecessary use of anti-TB treatments, and accelerated initiation of appropriate treatments.

Medicine (Baltimore) ; 98(34): e16787, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31441850


BACKGROUND: To determine the diagnostic accuracy of techniques with chronic thromboembolic pulmonary hypertension (CTEPH) patients via a protocol for systemic review and network meta-analysis. METHODS: We will search PubMed, EMBASE, Web of Science, and Google Scholar from inception to October 1, 2018. The reference lists of the retrieved articles are also consulted. Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) will be used to assess the risk of bias in each study. The direct meta-analyses, network meta-analyses, and ranking of competing diagnostic tests will be used by STATA 12.0 and WINBUGS 1.4. Heterogeneity and inconsistency are assessed. RESULTS: This study is ongoing, will be submitted to a peer-reviewed journal publication once completed. CONCLUSION: This study will provide a comprehensive evidence summary of diagnostic test accuracy in detecting the CTEPH, and can help patients and clinicians to select appropriate or best diagnostic test. ETHICS AND COMMUNICATION: No ethical approval and patient consent are required, because it is based on published researches. PROSPERO REGISTRATION NUMBER: CRD42019121279.

Int J Biometeorol ; 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385092


China is among the countries with the worst air quality throughout the world. As PM2.5 was not included in the national air quality monitoring network before January 2013 in China, no study has investigated the associations of ambient PM2.5 and O3 with cardiovascular mortality in Hefei, China. In this time-series analysis, Poisson regression in generalized additive model was adopted to assess the associations between the air pollutants and cardiovascular mortality during the 2013-2015 in Hefei, China. The findings showed that the daily average level of PM2.5 and O3 was 77.8 µg/m3 and 60.1 µg/m3 in the study period, respectively. PM2.5 and O3 exposure tended to increase cardiovascular mortality, but the associations were statistically insignificant. Further stratified analyses by seasons showed that with every 10 µg/m3 increase of PM2.5 in the cold season (October-March), the risk of cardiovascular death increased by 0.22% (95% CI 0.05%, 0.39%); while every 10 µg/m3 increase of O3 in the warm season (April-September), the risk of cardiovascular death increased by 1.29% (95% CI 0.26%, 2.33%) on Lag0. Interestingly, stratified analysis by gender showed that the associations of PM2.5, but not O3 exposure, could significantly increase cardiovascular mortality in females, but not males. The findings of this study especially underscored the adverse associations of PM2.5 and O3 exposure with females in specific seasons. More studies are needed to verify our findings and further investigate the underlying mechanisms. Graphical Abstract.

Curr Med Chem ; 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31419926


BACKGROUND: Thromboangiitis obliterans (TAO) is a nonatherosclerotic thrombotic-occlusive vasculitis that affects the vessels of the small and medium sized extremities. No explicit etiology or pathogenesis of TAO has been proven, and more effective treatments are needed.

Objective: To summarize and present an overview of recent advances regarding the risk factors, mechanisms and treatments of TAO and to organize the related information into figures to provide a comparatively complete reference.

Methods: We searched PubMed for English-language literature about TAO without article type limits, including articles about the risk factors, pathological mechanisms and treatments of TAO in the last 10 years with essential supplements (references over ranges and English abstracts of Russian literature).

Results: After screening content of literatures, 99 references were evaluated. We found that risk factors of TAO include smoking, gene factors and periodontal diseases. The underlying mechanism of TAO involves in oxidative stress, immunity, hemodynamic changes, inflammation and so on. Moreover, similarities in genetic factors and cigarette relevance existed between periodontal diseases and TAO, so further relationship study of them are required. For TAO treatment, medicine, endovascular intervention and revascularization surgery, autologous cell therapy and novel therapies were also mentioned. Besides, a hypothesis that infection triggers autoimmunity in TAO could be speculated, in which TLR4 plays a key role.

Conclusions: 1. Puts forward a hypothesis that infections can trigger autoimmunity in TAO development, in which TLR4, as a key role, can activate immune signaling pathways and induce autoimmune cytokines expression. 2. Suggests a reconsideration about the association between periodontal diseases and TAO, such as they just share the same high-risk population. Controlling periodontal disease severity in TAO studies may provide new clues. 3. For TAO treatment, endovascular intervention and autologous cell therapy both showed promising long-term therapeutic effectiveness, in which autologous cell therapy is becoming more popular, although more clinical comparisons needed.


BMC Pulm Med ; 19(1): 145, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409326


BACKGROUND: Aerosol administration is increasingly being used as a therapeutic intervention for mechanically ventilated preterm infants. However, the effects of inhalation therapy on retinopathy of prematurity (ROP) have not yet been explored. METHODS: A retrospective cohort study was conducted in a tertiary level neonatal intensive care unit (NICU) from 2011 to 2013. All preterm infants with a gestational age (GA) of 24~29 weeks receiving invasive intubation for more than 1 week in the NICU were included. Infants with severe congenital anomalies were excluded. ROP was defined as stage II or greater according to medical records by ophthalmologists. A multivariate logistic regression model was used to estimate the risk of ROP in relation to inhalation therapy after adjusting for confounders. RESULTS: In total, 205 infants were enrolled in this study, including 154 with inhalation therapy and 51 without inhalation therapy. Univariate analyses showed an association of inhalation with the following characteristics: sex (p = 0.047), GA (p = 0.029), sepsis (p = 0.047), bronchopulmonary dysplasia (BPD) (p < 0.001), and ROP (p = 0.001). Furthermore, logistic regression analysis indicated that inhalation therapy was an independent risk factor for ROP (odds ratio (OR) = 2.639; 95% confidence interval (CI) = 1.050~6.615). In addition, infants with a GA of 24~25 weeks (OR = 6.063; 95% CI = 2.482~14.81) and 26~27 weeks (OR = 3.825; 95% CI = 1.694~8.638) were at higher risk of ROP than those with a GA of 28~29 weeks. Other factors - including sex, sepsis, BPD, and delivery mode - did not carry significant risk. CONCLUSION: Aerosol therapy with pure oxygen delivery is associated with ROP. Clinicians should exercise great caution when conducting aerosol therapy with excess oxygen in mechanically ventilated preterm infants.

EBioMedicine ; 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31409574


BACKGROUND: Accumulating evidence has revealed the critical roles of N6-methyladenosine (m6A) modification of mRNA in various cancers. However, the biological function and regulation of m6A in bladder cancer (BC) are not yet fully understood. METHODS: We performed cell phenotype analysis and established in vivo mouse xenograft models to assess the effects of m6A-modified ITGA6 on BC growth and progression. Methylated RNA immunoprecipitation (MeRIP), RNA immunoprecipitation and luciferase reporter and mutagenesis assays were used to define the mechanism of m6A-modified ITGA6. Immunohistochemical analysis was performed to assess the correlation between METTL3 and ITGA6 expression in bladder cancer patients. FINDINGS: We show that the m6A writer METTL3 and eraser ALKBH5 altered cell adhesion by regulating ITGA6 expression in bladder cancer cells. Moreover, upregulation of ITGA6 is correlated with the increase in METTL3 expression in human BC tissues, and higher expression of ITGA6 in patients indicates a lower survival rate. Mechanistically, m6A is highly enriched within the ITGA6 transcripts, and increased m6A methylations of the ITGA6 mRNA 3'UTR promotes the translation of ITGA6 mRNA via binding of the m6A readers YTHDF1 and YTHDF3. Inhibition of ITGA6 results in decreased growth and progression of bladder cancer cells in vitro and in vivo. Furthermore, overexpression of ITGA6 in METTL3-depleted cells partially restores the BC adhesion, migration and invasion phenotypes. INTERPRETATION: Our results demonstrate an oncogenic role of m6A-modified ITGA6 and show its regulatory mechanisms in BC development and progression, thus identifying a potential therapeutic target for BC. FUND: This work was supported by National Natural Science Foundation of China (81772699, 81472999).

Mol Med Rep ; 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432175


Ion channels serve important roles in the excitation­contraction coupling of cardiac myocytes. Previous studies have shown that the overexpression or activation of intermediate­conductance calcium­activated potassium channel (SK4, encoded by KCNN4) in embryonic stem cell­derived cardiomyocytes can significantly increase their automaticity. The mechanism underlying this effect is hypothesized to be associated with the activation of hyperpolarization­activated cyclic nucleotide­gated channel 2 (HCN2). The aim of the present study was to explore whether a biological pacemaker could be constructed by overexpressing SK4 alone or in combination with HCN2 in a rat model. Ad­green fluorescent protein (GFP), Ad­KCNN4 and Ad­HCN2 recombinant adenoviruses were injected into the left ventricle of Sprague­Dawley rat hearts. The rats were divided into a GFP group (n=10), an SK4 group (n=10), a HCN2 group (n=10) and an SK4 + HCN2 (SK4/HCN2) group (n=10). The isolated hearts were perfused at 5­7 days following injection, and a complete heart block model was established. Compared with the GFP group, overexpressing SK4 alone did not significantly increase the heart rate after establishment of a complete heart block model [98.1±8.9 vs. 96.7±7.6 beats per min (BPM)], The heart rates in the SK4/HCN2 (139.9±21.9 BPM) and HCN2 groups (111.7±5.5 BPM) were significantly increased compared with the GFP and SK4 groups, and the heart rates in the SK4/HCN2 group were significantly increased compared with the SK4 or HCN2 groups. In the HCN2 (n=8) and the SK4/HCN2 (n=7) groups, the shape of the spontaneous ventricular rhythm was the same as the pacing­induced ectopic rhythm in the transgenically altered site. By contrast, these rhythms were different in the SK4 (n=10) and GFP (n=10) groups. There were no significant differences in action potential duration alternans or ventricular arrhythmia inducibility between the four groups (all P>0.05). Western blotting, reverse transcription­quantitative PCR and immunohistochemistry analyses showed that the expression levels of SK4 and HCN2 were significantly increased at the transgene site. Biological pacemaker activity could be successfully generated by co­overexpression of SK4 and HCN2 without increasing the risk of ventricular arrhythmias. The overexpression of SK4 alone is insufficient to generate biological pacemaker activity. The present study provided evidence that SK4 and HCN2 combined could construct an ectopic pacemaker, laying the groundwork for the development of improved biological pacing mechanisms in the future.

Food Chem ; 301: 125270, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377619


Dajiang is a popular Chinese fermented soybean condiment. Here, a comparative metaproteomic analysis of traditional and commercial dajiang was performed during fermentation. A total of 4250 and 1421 peptide sequences were obtained from 3493 and 1987 proteins in traditional and commercial dajiang, respectively. 4299 differentially expressed microbial proteins show a high metabolic heterogeneity between the two types of dajiang. The KEGG annotation indicated that there were some pathways related to human diseases, which suggest that some microbes in traditional dajiang fermentation may have greater food safety hazards. In combination with qualitative metabolomic analysis, we further traced metabolic intermediates and key enzymes in several main fermentation pathways of dajiang to be mainly affiliated with Penicillium, Tetracoccus and Bacillus in traditional samples, as well as Aspergilus in commercial samples. These results could provide information for the selection of strains that are more suitable to produce high quality dajiang and other fermented products.

Zhongguo Zhen Jiu ; 39(8): 875-7, 2019 Aug 12.
Artigo em Chinês | MEDLINE | ID: mdl-31397135


Opposing needling is an acupoint selection method of acupuncture recorded in Huangdi Neijing (Yellow Emperor 's Internal Classic). And the first record of dragon-tiger fighting needling is found in the Zhenjiu Daquan (Great Compendium on Acupuncture and Moxibustion), it is a compound reinforcing and reducing manipulation of tonification-purgation method. Both of them are widely used in the treatment of pain syndrome, which are mainly for nerve system and musculoskeletal diseases and seldom for gynecological diseases. By analyzing the pathogenic characteristics of chronic pelvic inflammation, the clinical application of opposing needling combined with dragon-tiger fighting needling for chronic pelvic inflammation is expounded based on the theory of treating different diseases with the same treatment in TCM.

Ren Fail ; 41(1): 650-656, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31296101


Objective: Accumulating evidence has demonstrated that dialysis patients are at increased risk for stroke. However, the impact of dialysis modalities on stroke risk remains controversial. We conducted a systematic review and meta-analysis to determine the effect of peritoneal dialysis (PD) and hemodialysis (HD) on stroke risk. Methods: A systematic search of PubMed, EMBASE, and Web of Science was performed to identify articles comparing the stroke outcomes of dialysis patients. Hazard ratios (HRs) with 95% confidence intervals (95% CIs) were extracted and synthesized to examine stroke outcomes, including ischemic stroke, hemorrhagic stroke, and overall stroke. Results: The search yielded five studies composed of 1,219,245 patients that were evaluated in the final analysis. The results showed that PD was associated with a lower risk for hemorrhagic stroke compared with HD (HR = 0.78; 95% CI: 0.69-0.88; p < 0.001). For ischemic stroke, the results showed that PD was associated with a higher risk compared with HD among the non-Asian patients (HR = 1.13; 95% CI: 1.05-1.23; p = 0.002), but there were no significant differences between PD and HD for the Asian patients. Similarly, there were no significant differences between the effects of the PD and HD approaches on overall stroke risk. Conclusions: We observed that PD patients were less likely to develop hemorrhagic stroke than HD patients, and the risk for ischemic stroke was significantly higher for PD patients than for HD patients among the non-Asian patients. However, our findings could be biased due to the heterogeneity of the included studies.

J Agric Food Chem ; 67(32): 8958-8966, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31334644


The functional role of human milk oligosaccharides (HMOs) is closely associated with their type, composition, and structure. However, a detailed analysis of HMOs is difficult because neutral oligosaccharides (NHMOs) are mixed with sialylated oligosaccharides (SHMOs) in milk. Here, NHMOs were separated from SHMOs by DEAE-52 anion chromatography, and lactose was removed by graphite carbon solid-phase extraction. Lactose-free NHMOs were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) based on Girard's reagent P on-target derivatization (GPOD), and SHMOs were analyzed by MALDI-TOF-MS following selective sialic acid derivatization and GPOD. Sixty-four oligosaccharides were detected: 36 NHMOs, of which 28 were fucosylated, and 28 SHMOs, of which 8 with α-2,3-linked monosialic acid, 2 with α-2,3-linked disialic acid, 10 with α-2,6-linked monosialic acid, 2 with α-2,6-linked disialic acid, and 5 with both α-2,3- and α-2,6-linked disialic acid. These findings provide the groundwork for further characterization of the structure and activity of HMOs.

Betaína/análogos & derivados , Leite Humano/química , Oligossacarídeos/química , Betaína/química , Feminino , Humanos , Ácido N-Acetilneuramínico/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
Brain Res ; 1721: 146347, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31348910


We previously reported that aquaporin 4 (AQP4) played a critical role in formation of brain edema and the altered expression of dystroglycan (DG) could relate with AQP4 expression after traumatic brain injury (TBI). However the mechanisms of this process remain unclear. DG was showed could act as a scaffold involved in adhesion-mediated signaling in ERK/MAPK pathway. We hypothesize that after scratch, extracellular α-DG and transmembrane ß-DG may act as the scaffold in scratch mechanical force activating ERK pathway which may regulate the expression of AQP4. Use ERK inhibitor and activator to confirm whether the expression of AQP4 is regulated by the activation of ERK pathway in scratched astrocytes. Use DG siRNA to confirm whether DG takes part in the process that the extracellular signal transduces into cell and activates the ERK pathway. The significant increase of AQP4 and DG expression induced by scratch could be abolished by blocking ERK signaling and enhanced by activating ERK signaling. Blockade of DG by siRNA led to no obvious effect of scratched-injury on the ERK signaling pathway. It demonstrated that DG may act as the scaffold in scratch mechanical force activating ERK pathway which can regulate the expression of AQP4 in astrocytes after scratch.

Plant Physiol Biochem ; 142: 53-58, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31272035


Tea contains high quantities and diverse types of triterpenoids, particularly in the form of saponins. However, little is yet known about the molecular basis of triterpenoid biosynthesis in tea plant. Here we report on isolation and functional analysis of squalene synthase (SQS) gene from tea plant (Camellia sinensis var. sinensis), which controls the biosynthesis of triterpenoids precursor. First, a full-length cDNA of squalene synthase, designated CsSQS, was isolated from tea plant. The protein is highly homologous to SQSs from other plants. Using CsSQS-reporter assays, CsSQS was demonstrated to be endoplasmic reticulum membrane-bound. The coding region of CsSQS excluding transmemberane sequence was expressed in Escherichia coli. Recombinant CsSQS catalyzed the formation of squalene using farnesyl-pyrophosphate (FPP) as substrate with NADPH and Mg2+. In tea plant leaves, CsSQS expression was significantly induced by both herbivore and mechanical damages. Consistent with the stronger induction of CsSQS expression by mechanical damage than herbivory, tea plants injured mechanically released squalene as a volatile compound, which however was not detected from herbivore-damaged tea plants. Furthermore, it was found that the flowers of another tea plant cultivar Camellia sinensis var. assamica contain higher concentrations of squalene than the cultivar sinensis, indicating variations among tea plant varieties. With the identification and molecular characterization of squalene synthase in tea plant, next, we can ask the questions about the roles of squalene as a volatile product as well as a precursor for triterpenoids, which may promote product development from diverse tea materials and mining of excellent tea germplasm resources.