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1.
Zhen Ci Yan Jiu ; 45(3): 180-7, 2020 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-32202708

RESUMO

OBJECTIVE: To investigate the protective effect of electroacupuncture(EA) on rats with ulcerative colitis (UC) and its effect on the Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear factor-kappa B (NF-κB) signaling pathway. METHODS: Sprague-Dawley rats were randomly divided into blank group, model group, salicylazosulfapyridine (SASP) group, low-intensity EA group, and high-intensity EA group, with 8 rats in each group. Enema with 2,4,6-trinitrobenzenesulfonic acid was performed to establish a model of UC. The rats in the two EA groups were given EA at"Tianshu" (ST25), "Guanyuan" (CV4), and "Zusanli"(ST36) for 15 min each time, once a day, with a current intensity of 1 mA for the low-intensity EA group and 5 mA for the high-intensity EA group(among them, "Tianshu" "Zusanli" bilateral alternate acupoints); the rats in the SASP group were given SASP suspension 3 mL every day by gavage. The course of treatment was 15 days for all groups. HE staining was used to observe the pathology of the colon and determine tissue damage index(TDI); ELISA was used to measure the serum levels of interleukin-4 (IL-4), interleukin-10 (IL-10), interleukin-17 (IL-17), and prostaglandin E2 (PGE2); immunohistochemical staining and real-time PCR were used to measure the protein and mRNA expression of TLR4, MyD88, and NF-κB in colonic tissue. RESULTS: Compared with the blank group, the model group had significant reductions in body weight, serum IL-4, and IL-10 (P<0.05) and significant increases in colonic mucosa TID, the serum levels of IL-17 and PGE2 and the protein and mRNA expression of TLR4, MyD88, and NF-κB in colonic tissue (P<0.05). Compared with the model group, the SASP group and the EA groups had significantly higher body weight and serum levels of IL-4 and IL-10 (P<0.05), as well as significantly lower colonic TDI, serum levels of IL-17 and PGE2, and integrated optical density and mRNA expression of TLR4, MyD88, and NF-κB in colonic tissue (P<0.05). Compared with the SASP group, the low-intensity EA group had significantly higher colonic TDI and protein and mRNA expression of TLR4, MyD88, and NF-κB in colonic tissue (P<0.05), and compared with the SASP group, the high-intensity EA group had a significantly higher body weight (P<0.05) and lower colonic TDI and protein and mRNA expression of TLR4, MyD88, and NF-κB in colonic tissue (P<0.05). Compared with the low-intensity EA group, the high-intensity EA group had significantly higher body weight (P<0.05), and lower colonic TDI and protein and mRNA expression of TLR4, MyD88, and NF-kB in colonic tissue (P<0.05). CONCLUSION: Electroacupuncture exerts a protective effect on the colonic mucosa in rats with UC possibly by inhibiting the TLR4/MyD88/NF-κB signaling pathway and reducing the release of inflammatory cytokines, and high-intensity EA may have a better effect than low-intensity EA.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32194160

RESUMO

OBJECTIVES: To investigate the prevalence of various electrocardiographic (ECG) abnormalities among HIV-positive and HIV-negative individuals. METHODS: This cross-sectional evaluation included 1412 HIV-positive and 2824 HIV-negative participants aged 18-75 years and frequency-matched by age and sex, derived from the baseline survey of Comparative HIV and Aging Research in Taizhou (CHART), China between February and December 2017. RESULTS: HIV-positive individuals had higher prevalence of sinus tachycardia (5.6% [79/1412] vs 1.3% [36/2824], p<0.001) and ST/T wave abnormalities (14.9% [211/1412] vs 9.4% [264/1412], p<0.001) but lower prevalence of sinus bradycardia (4.8% [68/1412] vs 7.5% [211/2824], p=0.001); such associations remained significantly after adjusting for traditional risk factors (adjusted odds ratio [aOR] 4.68, 95%CI 3.06-7.17; aOR 1.89, 95%CI 1.54-2.34; aOR 0.60, 95%CI 0.44-0.80; respectively). In adjusted models, being in higher carotid intima-media thickness categories were significantly associated with ST/T abnormalities in HIV-positive individuals only (0.78-1.00 mm: aOR 1.46, 95%CI 1.01-2.12; >1.00 mm: aOR 2.18, 95%CI 1.39-3.42), whereas being in higher blood pressure categories were significantly associated with both sinus tachycardia (prehypertension: aOR 5.61, 95%CI 1.76-17.91; hypertension: aOR 12.62, 95%CI 3.60-44.27) and ST/T abnormalities (hypertension: aOR 2.04, 95%CI 1.41-2.95) in HIV-negative individuals only. Longer duration of known HIV infection was the only HIV-specific factor of ST/T abnormalities (aOR 1.61, 95%CI 1.17-2.22), none was for sinus tachycardia. CONCLUSIONS: HIV infection is independently associated with sinus tachycardia and ST/T abnormalities. Further research is needed to investigate specific mechanisms by which HIV infection leads to ECG abnormalities and evaluate whether inclusion of ECG parameters improve CVD prediction. Integrating ECG screening into routine HIV care is recommended in China.

3.
Nat Cell Biol ; 22(3): 332-340, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32123336

RESUMO

Mapping of the holistic cell behaviours sculpting the four-chambered mammalian heart has been a goal or previous studies, but so far only success in transparent invertebrates and lower vertebrates with two-chambered hearts has been achieved. Using a live-imaging system comprising a customized vertical light-sheet microscope equipped with a mouse embryo culture module, a heartbeat-gated imaging strategy and a digital image processing framework, we realized volumetric imaging of developing mouse hearts at single-cell resolution and with uninterrupted cell lineages for up to 1.5 d. Four-dimensional landscapes of Nppa+ cardiomyocyte cell behaviours revealed a blueprint for ventricle chamber formation by which biased outward migration of the outermost cardiomyocytes is coupled with cell intercalation and horizontal division. The inner-muscle architecture of trabeculae was developed through dual mechanisms: early fate segregation and transmural cell arrangement involving both oriented cell division and directional migration. Thus, live-imaging reconstruction of uninterrupted cell lineages affords a transformative means for deciphering mammalian organogenesis.

4.
Immunobiology ; : 151915, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32122675

RESUMO

Gastric Cancer (GC) is the fifth leading cause of cancer-related death in the world, and in urgent need of specific therapeutic targets to acquire prominent effectiveness. T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif (ITIM) domain (TIGIT) and programmed cell death protein 1 (PD-1) are identified to be abnormally overexpressed in various types of cancers including GC. This study aimed to investigate whether TIGIT and PD-1 could serve as potential prognostic biomarkers for GC. Firstly, TCGA GC dataset analysis and correlation analysis were utilized to inspect the relationship between expression of TIGIT, PD-1 and CD8 + T cells in GC and adjacent normal tissues. Then, flow cytometry was used to verify the data after collecting the peripheral blood, GC and adjacent normal tissues from 150 GC patients. Lastly, quantitative RT-PCR was performed to detect the expression of CD155, CD113, CD112 and TIGIT in six human GC cell lines and 631 GC patients in KM Plotter Database to conduct prognostic analysis. As results, we found that TIGIT and PD-1 were upregulated in GC tissues with high CD8 + T cells infiltration, while correlation analysis indicated they were in high-positive correlation. In addition, the flow cytometry analysis further showed that the high-expression of TIGIT in tumor microenvironment of GC could suppress the function of infiltrative CD8 + T cells, which leads to the escape of GC cells from immune killing. Furthermore, CD155 and CD112 were found abnormally upregulated in GC tissues and cell lines and the high expression of CD155, CD112 and TIGIT demonstrated poor prognosis results. In conclusion, these results provided potential therapeutic targets and prognostic biomarkers for treatment of GC in clinic.

5.
Neuroreport ; 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32168101

RESUMO

Ischemic stroke damages the blood-brain barrier (BBB), which leads to brain edema and increases the risk of intracranial hemorrhage. Proteasome inhibition has been found to protect the BBB against cerebral ischemia by suppressing neuroinflammation-mediated matrix metalloproteases-9 (MMP-9) activation. We recently showed that ginsenoside Rd (Rd), a major active ingredient of Panax ginseng, could suppress proteasome-mediated inflammation and be efficient for treating ischemic stroke but downstream mechanisms were still unidentified. For this purpose, Sprague-Dawley rats were subjected to focal cerebral ischemic injury. The activity of proteasome and its downstream effectors nuclear factor-kappa B (NF-κB) and MMP-9 were evaluated. Rd reduced the activity of 20S proteasome in a cell-free assay and inhibited proteasome activity in brain lysates after ischemic stroke. Rd administration suppressed ischemic injury-induced NF-κB activity and IκB degradation mediated by the proteasome. Moreover, Rd reduced the activity and level of MMP-9, a downstream effector of NF-κB, and protected against BBB damage as evidenced by reduced Evan's Blue leakage and brain edema after cerebral ischemic injury. Jointly, these data demonstrate that ginsenoside Rd attenuates the pathogenesis of cerebral ischemia-induced BBB damage, probably by inhibiting proteasome activity and sequentially suppressing NF-κB/MMP-9 pathway.

6.
J Cell Mol Med ; 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32181567

RESUMO

Stem cell transplantation is a candidate method for the treatment of Leydig cell dysfunction-related diseases. However, there are still many problems that limit its clinical application. Here, we report the establishment of CXCR4-SF1 bifunctional adipose-derived stem cells (CXCR4-SF1-ADSCs) and their reparative effect on Leydig cell dysfunction. CD29+ CD44+ CD34- CD45- ADSCs were isolated from adipose tissue and purified by fluorescence-activated cell sorting (FACS). Infection with lentiviruses carrying the CXCR4 and SF1 genes was applied to construct CXCR4-SF1-ADSCs. The CXCR4-SF1-ADSCs exhibited enhanced migration and had the ability to differentiate into Leydig-like cells in vitro. Furthermore, the bifunctional ADSCs were injected into BPA-mediated Leydig cell damage model mice via the tail vein. We found that the CXCR4-SF1-ADSCs were capable of homing to the injured testes, differentiating into Leydig-like cells and repairing the deficiency in reproductive function caused by Leydig cell dysfunction. Moreover, we investigated the mechanism underlying SF1-mediated differentiation and testosterone synthesis in Leydig cells, and the B-box and SPRY Domain Containing Protein (BSPRY) gene was proposed to be involved in this process. This study provides insight into the treatment of Leydig cell dysfunction-related diseases.

7.
Cancer Lett ; 477: 19-30, 2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32120023

RESUMO

Immunotherapy targeting the PD-1/PD-L1 receptor has achieved great success in melanoma patients. Although many studies have addressed the underlying mechanisms involved in the blockade of PD-1/PD-L1 and the consequent modulation of the immune system, the mechanisms of PD-L1 upregulation and reliable biomarkers to predict the efficacy of anti-PD-1/PD-L1 therapy remain unknown. The present study demonstrates the correlation between IGFBP2 and PD-L1, revealing a novel immune-associated tumor function of IGFBP2 in facilitating nuclear accumulation of EGFR and activation of the EGFR/STAT3/PD-L1 signaling pathway in melanoma cells. Our results also suggest that combined IGFBP2 and PD-L1 expression has the potential to predict the efficacy of anti-PD-1 treatment for malignant melanoma; because the combination of high IGFBP2 and PD-L1 expression characterizes melanoma patients with worse overall survival and is associated with a better immune ecosystem. These characteristics have been confirmed by both in vitro and in vivo data. Consequently, IGFBP2 regulates PD-L1 expression by activating the EGFR-STAT3 signaling pathway and its function as a PD-L1 regulator might suggest novel therapeutic approach for melanoma.

8.
Oxid Med Cell Longev ; 2020: 5135893, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32190174

RESUMO

Objective: The mechanism of enhanced radiosensitivity induced by mitochondrial uncoupling protein UCP2 was investigated in HeLa cells to provide a theoretical basis as a novel target for cervical cancer treatment. Methods: HeLa cells were irradiated with 4 Gy X-radiation at 1.0 Gy/min. The expression of UCP2 mRNA and protein was assayed by real-time quantitative polymerase chain reaction and western blotting. UCP2 siRNA and negative control siRNA fragments were constructed and transfected into HeLa cells 24 h after irradiation. The effect of UCP2 silencing and irradiation on HeLa cells was determined by colony formation, CCK-8 cell viability, γH2AX immunofluorescence assay of DNA damage, Annexin V-FITC/PI apoptosis assay, and propidium iodide cell cycle assay. The effects on mitochondrial structure and function were investigated with fluorescent probes including dichlorodihydrofluorescein diacetate (DCFH-DA) assay of reactive oxygen species (ROS), rhodamine 123, and MitoTracker Green assay of mitochondrial structure and function. Results: Irradiation upregulated UCP2 expression, and UCP2 knockdown decreased the survival of irradiated HeLa cells. UCP2 silencing sensitized HeLa cells to irradiation-induced DNA damage and led to increased apoptosis, cell cycle arrest in G2/M, and increased mitochondrial ROS. Increased radiosensitivity was associated with an activation of P53, decreased Bcl-2, Bcl-xl, cyclin B, CDC2, Ku70, and Rad51 expression, and increased Apaf-1, cytochrome c, caspase-3, and caspase-9 expression. Conclusions: UCP2 inhibition augmented the radiosensitivity of cervical cancer cells, and it may be a potential target of radiotherapy of advanced cervical cancer.

9.
Injury ; 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32201118

RESUMO

BACKGROUND: There is little information on the cost and outcome of different treatments for femoral neck fractures. This study aimed to evaluate the cost-effectiveness of internal fixation compared with hemiarthroplasty (HA) for elderly patients with displaced femoral neck fractures. MATERIALS AND METHODS: A total of 121 patients ≥ 65 years old were divided into internal fixation (n = 58) or HA group (n = 63). Clinical outcome was evaluated by the EuroQol 5 dimensions (EQ-5D) score at 3, 12, and 24 months. The total costs including medical and non-medical expense were collected through hospitalisation information, cost diaries, and telephone interviews. A cost-utility analysis of the total costs in combination with quality-adjusted life years (QALYs) calculated by EQ-5D and survival time was conducted. Results were expressed in incremental cost-effectiveness ratio (ICER). RESULTS: The mean EQ-5D index score in the HA group were higher at the early follow-up (p<0.05). At 24 months there were no differences in EQ-5D between the 2 treatment groups (p>0.05). Over the 2-year period, patients treated with HA gained 0.09-0.10 more QALYs than those treated with internal fixation, while the mean total costs for internal fixation (CNY 55,676) were significantly lower than for HA (CNY 80,297) (P<0.001). ICER indicated that internal fixation may be more cost-effective than HA. CONCLUSION: HA is associated with better outcome than internal fixation in the treatment of displaced femoral neck fractures in elderly patients. However, internal fixation may be more cost-effective because of less total cost.

10.
Microb Pathog ; 143: 104135, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32165330

RESUMO

Mycoplasma bovis is a risky pathogen mainly responsible for pneumonia and mastitis in cattle. Up to date, its pathogenesis is not clear. Since secreted proteins have a tricky role in M. bovis pathogenesis, this study was designed to systematically reveal M. bovis secretome and potential role in virulence of the pathogen. By using bioinformatics tools, a total of 246 secreted proteins were predicted based on M. bovis genome. Among them, 14 were classical, 154 non-classical and 78 both pathways. Then by using 2-dimensional gel electrophoresis (2-DE) and Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF- MS), 169 proteins were revealed. Of them, 60 were predicted to be secreted including 3 classical, 43 non-classical, and 14 both classical and non-classical. Further 8 proteins (MbovP0038, MbovP0338, MbovP0341, MbovP0520, MbovP0581, MbovP0674, MbovP0693, MbovP0845) were predicted to be virulence-related factors with VFDB. In addition, MbovP0581 (ABC transporter protein) was validated experimentally as secreted in nature and highly immunogenic reacting with sera of cattle experimentally infected with M. bovis. In conclusion, this study might be a crucial step towards a better understanding of pathogenesis and leading to the development of novel diagnostic marker and potent vaccine against M. bovis.

11.
Clin Neurol Neurosurg ; 193: 105752, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32220712

RESUMO

OBJECTIVE: Neurocysticercosis (NCC) is the most common parasitic disease of the human central nervous system (CNS). However, a diagnosis of NCC may be hard to make if the specific clinical and routine neuroimaging manifestations are lacking, which hinders physicians from considering further immunodiagnostic tests. PATIENTS AND METHODS: Seven patients presented with fever, headache, nausea, cognitive decline, confusion, or progressive leg weakness. There were no pathogens found in the cerebrospinal fluid (CSF); patients were clinically suspected of meningoencephalitis or cerebrovascular disease. To clearly determine the etiology, next generation sequencing (NGS) of the CSF was used to detect pathogens in these seven patients. RESULTS: Taenia solium DNA sequences were detected in the seven patients, but not in the non-template controls (NTCs) or the other patients with clinically suspected CNS infections. Based on the patients' medical data and the diagnostic criteria for NCC, seven patients were diagnosed with probable NCC. The unique reads aligning to Taenia solium ranged from 6 to 261064, with genomic coverage ranging from 0.0003% to 14.8079%. The number of unique reads and genomic coverage dropped in three of the seven patients after antiparasitic treatment, consistent with the relief of symptoms. CONCLUSION: This study showed that NGS of the CSF might be an auxiliary diagnostic method for NCC patients. Larger studies are required.

12.
World J Gastroenterol ; 26(6): 645-656, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32103873

RESUMO

BACKGROUND: Reports on bacterial infection (BI) in decompensated cirrhosis (DC) is mainly from alcoholic cirrhosis. The role of BI as a trigger or complication of acute-on-chronic liver failure (ACLF) in patients with hepatitis B virus decompensated cirrhosis (HBV-DC) remains to be investigated. AIM: To investigate the impact of BI on the outcomes of the patients with HBV-DC admitted into the hospital with or without ACLF. METHODS: This retrospective study included patients with HBV-DC admitted to two tertiary centers in China. In-hospital overall survival, 90-d transplant-free survival, 5-year post-discharge survival, and cumulative incidence of ACLF were evaluated. Risk factors for death were analyzed considering liver transplantation as a competing event. RESULTS: A total of 1281 hospitalized HBV-DC patients were included; 284 had ACLF at admission. The overall prevalence of BI was 28.1%. The patients with BI had a significantly lower in-hospital survival and transplant-free 90-d survival than those without, in both the patients admitted with and without ACLF. The presence of BI significantly increased the risk of developing ACLF [sub-distribution hazard ratio (sHR) = 2.52, 95%CI: 1.75-3.61, P < 0.001] in the patients without ACLF. In the patients discharged alive, those who had an episode of BI had a significantly lower 5-year transplant-free survival. BI was an independent risk factor for death in the patients admitted without ACLF (sHR = 3.28, 95%CI: 1.93-5.57), while in ACLF admissions, the presence of pneumonia, but not other type of BI, independently increased the risk of death (sHR = 1.87, 95%CI: 1.24-2.82). CONCLUSION: BI triggers ACLF in patients with HBV-DC and significantly impairs short-term survival. HBV-DC patients should be monitored carefully for the development of BI, especially pneumonia, to avoid an adverse outcome.

13.
Chem Commun (Camb) ; 56(16): 2499-2502, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32003369

RESUMO

Hydroxyl alkylation of indoles by Friedel-Crafts reaction with a carbonyl compound is a useful strategy. However, the reaction was restricted to ketones due to the easy formation of a bisindole byproduct. Therefore, hydroxyl alkylation of an aldehyde with indole is confronted with great challenges. Here, we report an efficient strategy for asymmetric hydroxyl alkylation of 2-substituted indoles with aldehydes under 0.1 mol% chiral phosphoric acid. A series of α-hydroxyl ketones were obtained in high yields (up to 99%) and good enantioselectivities (up to 97%).

14.
Nanoscale ; 12(7): 4686-4694, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32048681

RESUMO

Hierarchical nanostructures with outstanding electrochemical properties and mechanical stability are ideal for constructing flexible hybrid supercapacitors. Herein, hierarchically hollow NiCo2S4@NiS nanostructures were designed and synthesized by sulfurizing the hierarchical NiCo double hydroxides (DHs) coated with nickel hydroxide nanostructures on carbon fabrics (NiCo-DHs@Ni(OH)2/CF), which trigger excellent electrochemical performances. The NiCo2S4@NiS/CF exhibits a high specific capacity of 1314.0 C g-1 at a current density of 1 A g-1, and maintains the rate performance at about 79.2% of the initial capacity at 30 A g-1. The hybrid supercapacitors of NiCo2S4@NiS//AC display a high energy density of 62.4 W h kg-1 at a power density of 800 W kg-1 with a remarkable cycling stability (96.2% of initial capacitance after 5000 cycles) and robust mechanical flexibility (no obvious decay of specific capacitance during various deformations). Consequently, NiCo2S4@NiS electrodes are expected to be a promising candidate for new smart energy storage devices with high security, stability and flexibility.

15.
Mol Med Rep ; 21(3): 1658-1666, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32016471

RESUMO

Resveratrol (RSV), a natural polyphenol found in grapes and other herbal plants, has been reported to possess anti­inflammatory, anti­oxidative and anti­proliferative activities. The aim of the present study was to investigate the effect of RSV on interleukin (IL)­33­induced inflammatory responses in mast cells and identify the underlying molecular mechanisms. Rat basophilic leukemia (RBL­2H3) cells were stimulated with IL­33 in the presence or absence of RSV. MTT, ELISA, reverse transcription­quantitative PCR and western blot analyses were then performed in order to assess cytotoxicity, inflammatory cytokine production, suppression of tumorigenicity 2 receptor expression, protein expression involved in mitogen­activated protein kinase (MAPK) and nuclear factor (NF)­κB signaling, respectively. Finally, rats were used to determine the biological effect of RSV in vivo. The results revealed that RSV inhibited cell viability and increased cytotoxicity in a dose­dependent manner. Medium concentration of RSV (10 µM) treatment attenuated inflammatory cytokine production, such as IL­6, IL­13, tumor necrosis factor­α and monocyte chemotactic protein­1, and curbed IL­33­induced enhancement of immunoglobulin E­mediated responses in RBL­2H3 cells, which were associated with the suppression of NF­κB­mediated transcription and inhibition of P38 phosphorylation in response to IL­33 stimulation, but not extracellular signal regulated kinase or JNK. Notably, RSV application also decreased the levels of inflammatory cytokines in rats induced by IL­33 injection, which was similar to the anti­inflammatory effect in vitro. The data from the present study demonstrated that RSV played a regulatory role in antagonizing the effects of IL­33 on mast cells both in vitro and in vivo, suggesting that it has therapeutic potential in IL­33­mediated inflammatory diseases that are associated with mast cells.

16.
J Mol Neurosci ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32002752

RESUMO

Metagenomics next-generation sequencing (mNGS) is increasingly available for the detection of obscure infectious diseases of the central nervous system. However, human DNA contamination from elevated white cells, one of the characteristic cerebrospinal fluid (CSF) features in meningitis patients, greatly reduces the sensitivity of mNGS in the pathogen detection. Currently, effective approaches to selectively reduce host DNA contamination from clinical CSF samples are still lacking. In this study, a total of 20 meningitis patients were enrolled, including 10 definitively diagnosed tuberculous meningitis (TBM) and 10 definite cryptococcal meningitis (CM) cases. To evaluate the effect of reduced human DNA in the sensitivity of mNGS detection, three specimen-processing protocols were performed: (i) To remove human DNA, saponin, a nonionic surfactant, was used to selectively lyse white cells in CSF followed by DNase treatment prior to the extraction of DNA; (ii) to reduce host DNA, CSF was centrifuged to remove human cells, and the supernatant was collected for DNA extraction; and (iii) DNA extraction from the unprocessed specimens was set as the control. We found that saponin processing significantly elevated the NGS unique reads for Cryptococcus (P < 0.01) compared with the control but had no effects for Mycobacterium tuberculosis (P > 0.05). However, detection of centrifuged supernatants improved the NGS unique reads for both TBM and CM compared with controls (P < 0.01). Our results demonstrate that the use of mNGS of centrifuged supernatants from clinical CSF samples in patients with TBM and CM is a simple and effective method to improve the sensitivity of pathogen detection.

17.
Sci Rep ; 10(1): 1709, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015468

RESUMO

Positive-intrinsic-negative (PIN) diodes are widely used as limiters to protect sensitive components from damage in radio frequency (RF) receiver systems and communication front-ends. However, PIN diode limiters can be burnt out due to the microwave pulses coupling through the front-end of RF receiver systems. The damage processes and mechanisms in PIN limiters are undoubtedly important topics. Here, the damage accumulation process in PIN limiters induced by external microwave pulses is studied via the injection experiments. The relationship between the degree of damage (i.e., insertion loss) in the limiters and number of the injected pulses is reported. The maximum temperature criterion for burnout in PIN limiters is theoretically predicted and experimentally verified not accurate, and it is further observed that the insertion loss of the PIN diode limiter changes significantly only if more energy is injected into the limiter via microwave pulses.

18.
Phys Chem Chem Phys ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32051988

RESUMO

Based on the newly developed SCAN meta-GGA and the widely used PBE-GGA functionals, ab initio molecular dynamics are performed on water. It is proved that, although the SCAN meta-GGA is not as good as the TIP4P/2005 model potential in describing the equation of state of water, it is much better than the PBE-GGA, the ST2 model potential, and ab initio trained neural network potentials. Moreover, the SCAN meta-GGA predicts a first-order liquid-liquid transition from high- to low-density water at negative pressure, in which the structures are qualitatively consistent with experimental observations, and the spinodal point of high-density water is very close to Speedy's stability limit line.

19.
Artigo em Inglês | MEDLINE | ID: mdl-32070936

RESUMO

Leiocassis longirostris is a common fish variety that is widely cultivated in China, during the breeding process however, it is highly susceptible to bacterial haemorrhagic septicemia, which can cause great economic loss for farmers. To understand the immune responses of L. longirostris to Aeromonas hydrophila infection, Illumina sequencing was employed to identify changes in the mRNA and miRNA in spleen tissue. In this study, a total of 92.16 and 95.61 million (M) high-quality transcriptome reads were generated from the control group (CG) and experimental group (EG) spleen samples, respectively, and 207 up-regulated and 185 down-regulated genes were identified. These genes were enriched in 29 GO terms and 30 KEGG pathways (P ≤ 0.05), including cytokine-cytokine receptor interaction and complement and coagulation cascades, with 17 up-regulated genes and 12 down-regulated genes related to immune responses in the EG relative to the CG. Based on the zebrafish genome, miRNA-seq identified a total of 343 miRNAs, of which 15 were up-regulated and 10 were down-regulated (fold-change ≥2 or ≤0.5 and P ≤ 0.05). Target gene prediction and KEGG enrichment analysis revealed that all of the target genes were concentrated in 13 pathways associated with immune response, including the mTOR signaling pathway and the TGF-beta signaling pathway. The expression patterns of 8 differentially expressed genes and 4 miRNAs involved in immune response were validated by quantitative real-time RT-PCR. These results have provided valuable insights into the molecular mechanisms underlying the immune response of L. longirostris to bacterial haemorrhagic septicemia.

20.
Anal Chem ; 92(4): 3293-3301, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-31973517

RESUMO

A convenient and efficient method to eliminate the aggregation effect of organic photoelectric sensing materials and to improve biological compatibility and cell permeability as well was developed by hanging organic fluorophores on a polymer chain, for example, fluorescein fluorophores had been controllably hung on polyacrylamide main chains with a 1:2 stoichiometric ratio by a simple copolymerization strategy. The results showed that introduction of water-soluble bioactive polyacrylamide main chains into fluorescein fluorophores via covalent bonds could effectively improve their optical stability by deteriorating π-π stack and charge-transfer interactions among different fluorophores. More importantly, the resultant materials possessed low toxicity and excellent cell permeability ten times larger than their precursor fluorescein fluorophore, which made it express an especially turn-on fluorescent response to ultratrace Hg2+ both in aqueous and living cells by forming stable 5-member-ring complexes with Hg2+ with a correlation coefficient of 0.997 and a low detection limit of 4.0 × 10-10 mol·L-1. This work provides promising insight into constructing some practical sensing materials for environmentally-friendly biological analyses.

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