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1.
Transl Psychiatry ; 10(1): 97, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32184386

RESUMO

Smoking is partly attributed to alterations of reward processing. However, findings on the neurobiological mechanisms that underlie smoking-related and smoking-unrelated reward processing in smokers have been inconsistent. Neuroimaging experiments that used functional magnetic resonance imaging (fMRI) and reported brain responses to smoking-related cues and nonsmoking reward-related cues in smokers and healthy controls as coordinates in a standard anatomic reference space were identified by searching the PubMed, Embase, and Web of Science databases up to December 2018. Three meta-analyses were performed using random-effect nonparametric statistics with Seed-based d Mapping software, with brain activity contrast from individual studies as the input. The striatum showed higher activation in response to smoking-related cues compared with neutral cues in 816 smokers from 28 studies and lower activation in response to nonsmoking reward-related cues in 275 smokers compared with 271 healthy control individuals from 13 studies. The relative reactivity of the putamen to smoking-related cues increased in 108 smokers compared with 107 healthy controls from seven studies. Meta-regression showed that smokers with a greater severity of nicotine dependence exhibited less engagement of the striatum in response to both smoking-related cues and nonsmoking reward-related cues. The present results reveal the disruption of reward system function in smokers and provide new insights into diverging theories of addiction. With the escalation of nicotine dependence, nicotine appears to exert dynamic effects on reward processing, based on incentive sensitization theory and reward deficiency syndrome theory.

2.
Transbound Emerg Dis ; 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32145150

RESUMO

African swine fever (ASF) is one of the most complex and lethally haemorrhagic viral diseases of swine, affecting all breeds and ages of pigs. In the absence of ASF vaccines, reliable laboratory diagnosis and restricted biosecurity are critical for disease prevention and control. A detection of ASF-specific antibodies in an unvaccinated pig is a good marker for the diagnosis of ASF. The immunoperoxidase test (IPT) is a sensitive test for detecting ASF virus (ASFV) antibodies. However, due to the complexity of the procedure, the IPT is only suitable to be used as a confirmatory test. The ASFV p30 protein-based enzyme-linked immunosorbent assay (ELISA) is widely used for ASFV antibody screening, but the sensitivity is not comparable to the IPT. It is essential to have a better understanding of the antigenic properties of ASFV p30 to improve p30-based serologic tests. In this study, we developed a panel of 21 monoclonal antibodies (mAbs) against ASFV p30. With 14 out of the 21 mAbs, we defined 4 antigenic regions that contain at least 4 linear epitopes. Nine of the 14 mAbs mapped to antigenic regions 3 and 4 reacted with p30 in all serologic methods tested in this study, such as indirect immunofluorescence assay (IFA), ELISA and Western blot. The antigenic regions 3 and 4 are highly conserved and immunodominant in host antibody response. These mAbs and the defined p30 antigenic regions 3 and 4 provide valuable tools for the development and improvement of ASF serologic assays.

3.
Virus Genes ; 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32198605

RESUMO

Seven strains of porcine reproductive and respiratory syndrome virus (PRRSV) were isolated from 2014 to 2017 in the Shandong province of China and their genomes were sequenced and analyzed. Results showed that all seven of the isolates belong to PRRSV 2, and are clustered into four lineages (lineage 1, 3, 5 and 8) based on comparisons of the ORF5 gene. Comparative analysis of genomes and specific amino acid sites revealed that three of the strains (SDwh1402, SDwh1602 and SDwh1701) have evolved directly from modified live virus (MLV) JXA1-P80, TJM-F92 and IngelvacPRRS. Further recombination analysis revealed that two of the strains (SDyt1401 and SDwh1601) were the result of a recombination event between MLVs JXA1-P80 and NADC30 while two other strains (SDwh1403 and SDqd1501) were the result of recombination between MLVs IngelvacPRRS and NADC30 and HP-PRRSV and QYYZ, respectively. Our results add to the data on MLV evolution and PRRSV recombination and provide a better understanding of the epidemiology of PRRSV in China.

4.
Anal Bioanal Chem ; 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32206848

RESUMO

The accurate analysis of single-nucleotide polymorphisms is of great significance for clinical detection and diagnosis. Based on the hybridization hindrance caused by graphene oxide (GO) and hairpin probe, we report a T7 Exo-assisted cyclic amplification technique to distinguish single-base mismatch for highly sensitive and selective detection of mutant-type DNA. When the mutant-type target is completely complementary to the probe, the T7 Exo hydrolyzes the probe and releases the fluorescent molecule from the GO surface, resulting in a fluorescence signal. Conversely, when the wild-type mismatch target is present, the weak hybridization prevents the release of FAM-labeled probe from the GO surface. Therefore, the FAM-labeled probe cannot be degraded efficiently by T7 Exo, and the fluorescence is still quenched by GO. The detection limit of the proposed method can be as low as 34 fM due to the cyclic signal amplification. The experimental results showed that the established method could be used to detect single-nucleotide polymorphisms accurately and sensitively at low cost.

5.
BMC Infect Dis ; 20(1): 193, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32131752

RESUMO

BACKGROUND: Microbial infection is the main cause of increased morbidity and mortality in burn patients, especially infections caused by multiple drug-resistant organisms (MDRO). The purpose of this study was to explore major microbial trends in burn patients. METHODS: This retrospective study was conducted at burn wards and intensive care units, where burn patients were admitted following an event of dust explosion. Data were collected for a number of variables including severity of burns, demographic and clinical characteristics, laboratory data, and therapeutic devices. RESULTS: A total of 1132 specimens were collected from 37 hospitalized burn patients with mean TBSA of 46.1%.The most commonly isolated species were Staphylococcus spp. (22.4%). The highest rate of antibiotic resistance was observed in carbapenem-resistant A. baumannii (14.6%), followed by methicillin-resistant S. aureus (11.3%). For each additional 10% TBSA, the isolation of MDRO increased 2.58-17.57 times (p < 0.05); for each additional 10% of the third-degree burn severity, the risk of MDRO significantly decreased by 47% (95% CI, 0.38-0.73, p < 0.001) by Cox model. CONCLUSIONS: The proportion of overall microbial isolates increased with the increase in TBSA and duration of time after burns. The extent of TBSA was the most important factor affecting MDRO.

7.
Rev Sci Instrum ; 91(1): 014706, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012551

RESUMO

A novel diode featuring an annular cathode and a ring-shaped focusing electrode and operating in a low guiding magnetic field (GMF) has been developed. It was found that the breakdown threshold for a focusing electrode made of titanium was 140 kV/cm higher than a stainless steel electrode for the same operating conditions. Comparison of the diode current measured by a Rogowski coil and the beam current measured by a Faraday cup at the collector indicated that an intense relativistic electron beam was transmitted effectively even in a GMF of as low as 0.21 T. In addition, a photo of the cathode plasma and the targeting results indicated that the emission uniformity of the graphite cathode was satisfactory.

8.
Virus Res ; 279: 197871, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32004574

RESUMO

In the absence of a vaccine for African swine fever virus (ASFV), diagnostic tools are critical for early detection and implementation of control measures. Along with other immunogenic proteins, p54 is a good serological target for conducting ASF detection and surveillance. In this study, a panel of 12 mouse monoclonal antibodies (mAbs) was prepared against a baculovirus-expressed p54(60-178) polypeptide. Further screening showed that five mAbs were positive for reactivity against ASFV-infected cells and recombinant p54 proteins. Mapping studies using five polypeptides and 12 oligopeptides, showed that mAb #154-1 recognized a conserved polypeptide sequence, p54(65-75), and was placed into Group 1. Mabs #143-1 and #7 recognized a region covered by p54(93-113) and were placed into Group 2. Group 3 consisted of mAbs #101 and #117, which recognized p54(118-127). Sera from pigs infected with the low virulent OURT 88/3 strain recognized the same p54 region covered by the Group 3 mAbs. When tested in a neutralization format, only mAb #143-1 showed neutralization activity above background. Together, the results identify important antigenic and immunogenic regions located on p54, which provide new tools for improving ASFV diagnostics.

9.
Macromol Rapid Commun ; 41(6): e1900583, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32009279

RESUMO

A unique cuboid spider silk from the outer egg sac of Nephila pilipes, with an unusual square cross-section, is disclosed. The structure-function relationships within this silk are first studied through structural characterization, mechanical measurement, protein conformation, and polypeptide signature of silk proteins. This silk maintains the higher stiffness property of egg sac silks, and also shows a species difference. Environmental response of the mechanical properties within this silk are observed. Synchrotron FTIR microspectroscopy is used to monitor the silk protein conformation in a single natural silk. The ß-sheet structure aligns parallel to the fiber axis with a content of 22% ± 2.6%. The de novo resulting polypeptide from the solid silk fibers are novel, and an abundant polar amino acid insertion is observed. Short polyalanine (An , n ≤ 3), alternating serine and alanine (S/A)X, and alternating glycine and alanine (G/A)X, GGX, and SSX dominates in the resulting de novo polypeptide. This accords with the composition pattern of other egg sac silk proteins, besides the rarely observed GGX. This study broadens the library of egg sac spider silks and provides a new perspective to uncover structure-function relationships in spider silk.

10.
Sci Total Environ ; 717: 137021, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32062249

RESUMO

Biochar is a cost-effective and multifunctional carbon material, which can be used to immobilize heavy metal (HM) in soil. To date, the immobilization of different HM by various biochars are well-studied, however, little is known about the release condition of the immobilized HM. As the released HM may bring a threat to the soil environment, it is critical to understand the release pattern of biochar-sorbed HM in soil. Herein, six wheat straw-derived biochars (WBs) pyrolyzed under different temperature and duration time were loaded with zinc(Zn (II)), and the evolution of Zn(II) fractions in soils remediated by WBs over time was investigated by Community Bureau of Reference (BCR) three-step sequential extraction method. The main Zn(II) species sorbed on WBs were the Zn(II) sorbed on the acidic functional groups of WB and that sorbed on WB surface via electrostatic interaction. Generally, Zn(II) sorbed on high-temperature WB was more mobile than that sorbed on low-temperature WB. In the red soil, the soluble and exchangeable Zn(II) (i.e., Zn(II) in Fraction 1) in WB was inclined to transform to organic matter associated-Zn(II) (i.e., Zn(II) in Fraction 3) and residual Zn(II) (i.e., Zn(II) in Fraction 4). In the yellow-brown soil, the soluble and exchangeable Zn(II) in WB was prone to convert into amorphous Fe/Mn oxide associated-Zn(II) (i.e., Zn(II) in Fraction 2) and residual Zn(II). These results imply that Zn(II) sorbed by WB has the risk to be released into the soil environment, and WB produced at low temperature are more suitable to remediate soils with low/neutral pH.

11.
Sci Rep ; 10(1): 3165, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32081941

RESUMO

Human papillomavirus (HPV) infection contributes to most anal cancers and premalignant intraepithelial lesions. This study investigated anal HPV infections and cytological abnormalities among men who have sex with men (MSM). Sociodemographic characteristics and sexual behaviors were collected by using a structured questionnaire. Anal cytological results were examined, and HPV genotyping was performed by the Linear Array HPV Genotyping test. Logistic regression was used to estimate risk factors and their associations with high-risk HPV infection and cytological abnormalities. Among 163 MSM, 101 were seropositive for human immunodeficiency virus (HIV) and 62 were seronegative for HIV. The overall prevalence of HPV was 66.2%. A total of 61.9% and 48.2% of participants had never acquired any of either the quadrivalent or nonavalent vaccine HPV types, respectively. Cytological findings showed 15.3% atypical squamous cells of undetermined significance, 16.6% low-grade squamous intraepithelial lesion, 4.9% atypical squamous cells that cannot exclude high-grade squamous intraepithelial lesion and 17% high-grade squamous intraepithelial lesion. The number of high-risk HPV types was the predominant risk factor for abnormal anal cytology (OR 2.02, 95% CI 1.27-3.24). Infection with high-risk HPV was a significant predictor for cytological abnormality. MSM should be encouraged to obtain the HPV vaccine.

12.
Obes Surg ; 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32060852

RESUMO

BACKGROUND: Single-incision laparoscopic sleeve gastrectomy (SILSG) has been proposed as an alternative to conventional laparoscopic sleeve gastrectomy (CLSG) in obese patients. This study aims to compare the surgical outcomes of these two techniques. METHODS: A meta-analysis of existing literature obtained through a systematic literature search in the PubMed, EMBASE, and Cochrane Library CENTRAL databases from 2009 to 2019 was conducted. RESULTS: Eleven articles including 1168 patients were analyzed. Patients in the SILSG group reported greater satisfaction with cosmetic scar outcomes than those in the CLSG group (SMD = 2.47, 95% CI = 1.10 to 3.83, P = 0.00). There was no significant difference between the SILSG group and the CLSG group regarding operative time, intraoperative estimated blood loss, conversion rate, intraoperative complications, length of hospital stay, postoperative analgesia, postoperative complications, excess weight loss (EWL), and improvements in comorbidities (P > 0.05). CONCLUSIONS: Compared to CLSG, SILSG resulted in improved cosmetic satisfaction and showed no disadvantages in terms of surgical outcomes; thus, SILSG can serve as an alternative to CLSG for obese patients. Nonetheless, high-quality randomized controlled trials (RCTs) with large study populations and long follow-up periods are needed.

13.
Fish Physiol Biochem ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32072342

RESUMO

Autophagy is an important evolutionary conserved process in eukaryotic organisms for the turnover of intracellular substances. Recent studies revealed that autophagy displays circadian rhythms in mice and zebrafish. To date, there is no report focused on the rhythmic changes of autophagy in fish skeletal muscles upon nutritional deprivation. In this study, we examined the circadian rhythms of 158 functional genes in tilapia muscle in response to starvation. We found that 12 genes were involved in autophagy changed their rhythm after starvation. Among these genes, Atg4c, Bnip3la, Lc3a, Lc3b, Lc3c, and Ulk1a exhibited a daily rhythmicity in tilapia muscle, and Atg4b, becn1, bnip3la, bnip3lb, Lc3a, and ulk1b were significantly upregulated in response to starvation. The number of autophagosomes was dramatically increased in fasted fish, indicating that nutritional signals affect not only the muscular clock system but also its autophagy behavior. Administration of GSK4112, an activator of Nr1d1, altered rhythmic expression of both circadian clock genes and autophagy genes in tilapia muscle. Taken together, these findings provide evidence that nutritional deficiency affects both circadian regulation and autophagy activities in skeletal muscle.

14.
iScience ; 23(3): 100895, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32088394

RESUMO

Targeting memory reconsolidation is an effective intervention for treating posttraumatic stress disorder (PTSD). Disrupting unconditioned stimulus (US)-retrieval-induced fear memory reconsolidation has become an effective therapeutic approach to attenuate fear memory, but the underlying molecular mechanisms remain unknown. Here, we report that US-retrieval-dependent increase in phosphatidylinositol 4-kinase IIα (Pi4KIIα) promotes early endosomal trafficking of AMPA receptors, leading to the enhancement of synaptic efficacy in basolateral amygdala (BLA) neurons. The inhibition of Pi4KIIα by an inhibitor or short hairpin RNA impaired contextual fear memory reconsolidation. This disruptive effect persisted for at least 2 weeks, which was restored by Pi4KIIα overexpression with TAT-Pi4KIIα. Furthermore, the blockade of early endosomal trafficking following US retrieval reduced synaptosomal membrane GluA1 levels and decreased subsequent fear expression. These data demonstrate that Pi4KIIα in the BLA is crucial for US-retrieval-induced fear memory reconsolidation, the inhibition of which might be an effective therapeutic strategy for treating PTSD.

15.
J Org Chem ; 85(6): 4373-4385, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32067459

RESUMO

CuBr2-mediated intramolecular oxidative cyclopropanation of α-oxo ketene N,S-acetals was efficiently achieved to afford 2-thioalkyl-3-azabicyclo-[3.1.0]hexenes under mild conditions. 2-Oxyalkyl- and 2-aminoallyl-3-azabicyclo-[3.1.0]hexenes were also obtained from the corresponding α-oxo ketene N,O- and N,N-acetals. Further C-S bond transformations led to diverse 2-aryl-substituted 3-azabicyclo[3.1.0]hexene derivatives in good to high yields.

16.
ACS Chem Biol ; 15(3): 632-639, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32069008

RESUMO

Post-translational modifications play vital roles in fine-tuning a myriad of physiological processes, and one of the most important modifications is acetylation. Here, we report a ligand-directed site-selective acetylation using KHAc, a derivative of a phosphoglycerate mutase 1 (PGAM1) inhibitor. KHAc binds to PGAM1 and transfers its acetyl group to the ε-NH2 of Lys100 to inactivate the enzyme. The acetyl transfer process was visualized by time-resolved crystallography, demonstrating that the transfer is driven by proximity effects. KHAc was capable of selectively and effectively acetylating Lys100 of PGAM1 in cultured human cells, accompanied by inhibited F-actin formation. Similar strategies could be used for exogenous control of other lysine post-translational modifications.

17.
Nat Prod Res ; : 1-8, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32000518

RESUMO

Two new 2H-pyranones (1 and 2), two new isocoumarins (4 and 5), and two known compounds (3 and 6) were obtained from solid cultures of the endophytic fungus Pestalotiopsis microspora SC3082. Their structures and revision of the absolute stereochemistry of 6 were established by spectroscopic analyses and computational calculations. Compounds 2, 4 and 6 displayed moderate antifungal activities against Candida albicans ATCC 10321 with MIC values of 25.0, 25.0, and 12.5 µg/mL, respectively.

18.
J Antibiot (Tokyo) ; 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31949315

RESUMO

Eight new fasamycin-type polyketides, streptovertimycins A-H (1-8), were isolated from soil-derived Streptomyces morookaense SC1169 cultivated on wheat grains. Their structures were established by extensive spectroscopic analysis and theoretical computations of ECD spectra. Compounds 1-8 have a fasamycin-type pentacyclic structure featuring a 15-O-methyl group. They exhibited potent activity against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE) with MIC values in the range of 0.63-5.0 µg/ml. The activity profile provided new insights into the structure-activity relationships of fasamycin-type antibiotics.

19.
Cell Death Differ ; 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959915

RESUMO

The identification of viability-associated long noncoding RNAs (lncRNAs) is a means of uncovering therapeutic approaches for hepatocellular carcinoma (HCC). In addition, aberrant genome-wide hypomethylation has been implicated in HCC initiation and progression. However, the relationship between lncRNA dysregulation and genome-wide hypomethylation in hepatocarcinogenesis has not been fully elucidated. A novel lncRNA named LINC00662 was previously demonstrated to play a role in gastrointestinal cancer. In this study, we demonstrated that this lncRNA was correlated with survival and exhibited oncogenic properties, both in vitro and in vivo. Moreover, we determined that LINC00662 could lead to genome-wide hypomethylation and alter the genomic methylation profile by synchronously reducing the S-adenosylmethionine (SAM) level and enhancing the S-adenosylhomocysteine (SAH) level. Mechanistically, LINC00662 was determined to regulate the key enzymes influencing SAM and SAH levels, namely, methionine adenosyltransferase 1A (MAT1A) and S-adenosylhomocysteine hydrolase (AHCY), by RNA-RNA and RNA-protein interactions. In addition, we demonstrated that some SAM-dependent HCC-promoting genes could be regulated by LINC00662 by altering the methylation status of their promoters via the LINC00662-coupled axes of MAT1A/SAM and AHCY/SAH. Taken together, the results of this this study indicate that LINC00662 could be a potential biomarker for HCC therapy. More importantly, we proposed a new role of lncRNA in regulating genomic methylation to promote oncogene activation.

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