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2.
World J Clin Cases ; 7(23): 3980-3989, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31832400

RESUMO

BACKGROUND: In previous studies, celiomesenteric trunk (CMT) was narrowly defined as a hepato-gastro-spleno-mesenteric (HGSM) trunk, but other possible types were ignored. With the widespread use of multidetector computed tomography (MDCT) angiography, it is easy to collect a large sampling of data on arterial anatomy of the abdomen in daily radiological practice. A new classification system for CMT may be created based on its MDCT angiographic findings and variation patterns. AIM: To identify the spectrum and prevalence of CMT according to a new classification based on MDCT angiographic findings, and discuss the probable embryological mechanisms to explain the CMT variants. METHODS: A retrospective study was carried out on 5580 abdominal MDCT angiography images. CMT was defined as a single common trunk arising from the aorta and its branches including the superior mesenteric artery and at least two major branches of the celiac trunk. Various types of CMT were investigated. RESULTS: Of the 5580 patients, 171 (3.06%) were identified as having CMT. According to the new definitions and classification, the CMT variants included five types: I, II, III, IV and V, which were found in 96 (56.14%), 57 (33.33%), 4 (2.34%), 3 (1.75%) and 8 (4.68%) patients, respectively. The CMT variants also were classified as long type (106 patients, 61.99%) and short type (65 patients, 38.01%) based on the length of single common trunk. Further CMT classification was based on the origin of the left gastric artery: Type a (92 patients, 53.80%), type b (57 patients, 33.33%), type c (11 patients, 6.43%) and type d (8 patients, 4.68%). CONCLUSION: We systematically classified CMT variants according to our new classification system based on MDCT angiographic findings. Dislocation interruption, incomplete interruption and persistence of the longitudinal anastomosis could all be embryological mechanisms of various types of CMT variants.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31825666

RESUMO

Mitochondrial dysfunctions are responsible for myocardial injury upon ischemia/reperfusion (I/R) and mitochondrial E3 ubiquitin ligase 1 (Mul1) plays an important role in maintaining mitochondrial functions. This study aims to explore the function of Mul1 in myocardial I/R injury and the underlying mechanisms. The SD rat hearts were subjected to 1h-ischemia plus 3h-reperfusion, which showed the I/R injury (increase in infarct size and creatine kinase release), the elevated total and mitochondrial protein levels of Mul1 and p53, accompanied by the enhanced interactions between Mul1 and p53 as well as p53 and small ubiquitin-like modifier (SUMO1). Consistently, hypoxia/reoxygenation (H/R)-treated cardiac (H9c2) cells displayed cellular injury (apoptosis and necrosis), up-regulation of total and mitochondrial protein levels of Mul1 and p53, and enhanced interactions between p53 and SUMO1 concomitant with mitochondrial dysfunctions (increase in mitochondrial membrane potential and reactive oxygen species production while decrease in ATP production); these phenomena were attenuated by knockdown of Mul1 expression. Based on these observations, we conclude that a novel role of Mul1 has been identified in the myocardial mitochondria, where Mul1 stabilizes and activates p53 through its function of SUMOylation following I/R, leading to p53-mediated mitochondrial dysfunction and cell death.

4.
Acta Otolaryngol ; : 1-6, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31825723

RESUMO

Background: Auditory steady-state response (ASSR) and click-evoked auditory brain response (c-ABR) have been used for hearing assessment for decades years, the correlation of the two methods and the effects of type and degree of hearing loss (HL) to the correlation in infants younger than 6 months of age are unclear.Objectives: To compare the correlation of ASSR and c-ABR and then to analyse the effects of type and degree of HL on the correlation in infants younger than 6 months of age.Material and methods: Retrospective study comparing ASSR thresholds at various frequencies with c-ABR thresholds. 182 ears from 96 infants were assessed and classified according to types and degrees of HL.Results: The correlation coefficients were: 0.823, 0.864, 0.891, 0.871, 0.908, 0.915 and 0.913 between ASSR thresholds at 0.5, 1, 2, 4, 2-4, 1-2-4, 0.5-1-2-4 kHz and c-ABR thresholds respectively. The correlation coefficients in the group of sensorineural HL (SHL) (r = 0.763-0.900) were higher than conductive HL (r = 0.309-0.619) across all frequencies. The coefficients of severe-profound SHL (r = 0.595-0.790) were higher than mild-moderate SHL (r = 0.434-0.687) across all frequencies.Conclusions and significance: ASSR was one valuable cross-check measure by providing frequency specific information in auditory assessment.

5.
Org Lett ; 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31808697

RESUMO

Here we report a Ag-catalyzed [3 + 2] cycloaddition reaction between aryl diazonium salts and Seyferth-Gilbert reagent in a regioselective manner. This operationally simple transformation proceeds in an atom-economical way under mild reaction conditions, providing facile access to a broad set of phosphonylated tetrazoles. The synthetic utility of this method is further showcased by a straightforward procedure from upstream aromatic amines, denitrogenation transformations, and preparation of a phosphonylated drug scaffold.

6.
Elife ; 82019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31846423

RESUMO

σS is a master transcription initiation factor that protects bacterial cells from various harmful environmental stresses including antibiotic pressure. Although its mechanism remains unclear, it is known that full activation of σS-mediated transcription requires a σS-specific activator, Crl. In this study, we determined a 3.80 Å cryo-EM structure of an Escherichia coli transcription activation complex (E. coli Crl-TAC) comprising E. coli σS-RNA polymerase (σS-RNAP) holoenzyme, Crl, and a nucleic-acid scaffold. The structure reveals that Crl interacts with domain 2 of σS (σS2) and the RNAP core enzyme, but does not contact promoter DNA. Results from subsequent hydrogen-deuterium exchange mass spectrometry (HDX-MS) indicate that Crl stabilizes key structural motifs within σS2 to promote the assembly of the σS-RNAP holoenzyme and also to facilitate formation of an RNA polymerase-promoter DNA open complex (RPo). Our study demonstrates a unique DNA contact-independent mechanism of transcription activation, thereby defining a previously unrecognized mode of transcription activation in cells.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31880387

RESUMO

Water splitting is one of the most promising solutions for storing solar energy in a chemical bond. Water oxidation is still the bottleneck step because of its inherent difficulty and the limited understanding of the O-O bond formation mechanism. Molecular catalysts provide a platform for understanding this process in depth and have received wide attention since the first Ru-based catalyst was reported in 1982. Ru(V)=O is considered a key intermediate to initiate the O-O bond formation via either a water nucleophilic attack (WNA) pathway or a bimolecular coupling (I2M) pathway. Here, we report a Ru-based catalyst that displays water oxidation reactivity with Ru(IV)=(O) with the help of a redox-active ligand at pH 7.0. The results of electrochemical studies and DFT calculations disclose that ligand oxidation could significantly improve the reactivity of Ru(IV)=O toward water oxidation. Under these conditions, sustained water oxidation catalysis occurs at reasonable rates with low overpotential ( ~ 183 mV).

8.
Zootaxa ; 4560(2): zootaxa.4560.2.10, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31716587

RESUMO

A new species of Nemacheilidae, Triplophysa sanduensis sp. nov., is described here based on specimens collected from a small cave in Dengguang Village, Zhonghe Town, Sandu County, Guizhou Province, China. The new species can be distinguished from its congeners by the following combination of characters: branched dorsal-fin rays 8-9; branched pectoral-fin rays 8-9; branched pelvic-fin rays 5; branched anal-fin rays 5; vertebrae 4+37; snout length 45.5-50.1% of head length; postdorsal length 39.0-42.8% of standard length; caudal-peduncle depth/caudal-peduncle length range from 56.4% to 71.9%; the posterior chamber of the gas bladder degenerated; body elongated, covered by scattered scales; eyes present and normal in size, not reduced or absent; and a complete lateral line. A phylogenetic analysis based on the mitochondrial cytochrome oxidase subunit 1 (COI) gene resolved Triplophysa sanduensis as sister to Triplophysa longliensis. Kimura's 2-parameter genetic distance of the COI gene sequences between these two species was 1.9%.


Assuntos
Cipriniformes , Animais , China , Olho , Filogenia
9.
J Agric Food Chem ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31721582

RESUMO

A series of compounds with potential activity to induce plant resistance was synthesized from indole and thiol compounds and methodically evaluated for antiviral activity. The results indicated that some of the synthesized compounds had high antipotato virus Y (PVY), anticucumber mosaic virus, and antitobacco mosaic virus activities. Notably, compound D21 exhibited the best activity against PVY among these compounds in vivo, and the 50% effective concentrations (EC50) of protection activity is 122 µg/mL, which was distinctively better than the corresponding values for ribavirin (653 µg/mL), Ningnanmycin (464 µg/mL), and Xiangcaoliusuobingmi (279 µg/mL). Interestingly, we found that the protection activity of D21 was associated with improvement of chlorophyll content and defense-related enzyme activities. Moreover, D21 could trigger the malate dehydrogenase (MDH) signaling pathway, as further confirmed by the MDH activity evaluation. Hence, D21 can protect plants against viral activity and has potential as a novel activator for plant resistance induction.

10.
Cell Mol Neurobiol ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31722050

RESUMO

Ac2-26, a mimetic peptide of Annexin-A1, plays a vital role in the anti-inflammatory response mediated by astrocytes. In this study, we aimed to explore the underlying mechanisms of Ac2-26-mediated anti-inflammatory effect. Specifically, we investigated the inhibitory effects of Ac2-26 on lipopolysaccharide (LPS)-induced astrocyte migration and on pro-inflammatory cytokines and chemokines expressions, as well as one glutathione (GSH) reductase mRNA and total intracellular GSH levels in LPS-induced astrocytes. Additionally, we investigated whether mitogen-activated protein kinases (MAPK) and nuclear factor kappa-B (NF-κB) signaling pathway were involved in this process. Finally, we evaluated the analgesic effect of Ac2-26 in complete Freund's adjuvant (CFA)-induced inflammatory pain model. Our results demonstrated that Ac2-26 inhibited LPS-induced astrocytes migration, reduced the production of pro-inflammatory mediators [tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1 (MIP-1α)] and upregulated GSH reductase mRNA and GSH levels in LPS-induced astrocytes in vitro. This process was mediated through the p38, JNK-MAPK signaling pathway, but not dependent on the NF-κB pathway. Furthermore, the p38 and JNK inhibitors mimicked the effects of Ac2-26, whereas a p38 and JNK activator anisomycin partially reversed its function. Finally, Ac2-26 treatment reduced CFA-induced activation of astrocytes and production of inflammatory mediators in the spinal cord. These results suggest that Ac2-26 attenuates pain by inhibiting astrocyte activation and the production of inflammatory mediators; thus, this work presents Ac2-26 as a potential drug to treat neuropathic pain.

11.
Nano Lett ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31771332

RESUMO

The magnetic properties in two-dimensional van der Waals materials depend sensitively on structure. CrI3, as an example, has been recently demonstrated to exhibit distinct magnetic properties depending on the layer thickness and stacking order. Bulk CrI3 is ferromagnetic (FM) with a Curie temperature of 61 K and a rhombohedral layer stacking, whereas few-layer CrI3 has a layered antiferromagnetic (AFM) phase with a lower ordering temperature of 45 K and a monoclinic stacking. In this work, we use cryogenic magnetic force microscopy to investigate CrI3 flakes in the intermediate thickness range (25-200 nm) and find that the two types of magnetic orders, hence the stacking orders, can coexist in the same flake with a layer of ∼13 nm at each surface being in the layered AFM phase similar to few-layer CrI3 and the rest in the bulk FM phase. The switching of the bulk moment proceeds through a remnant state with nearly compensated magnetic moment along the c-axis, indicating formation of c-axis domains allowed by a weak interlayer coupling strength in the rhombohedral phase. Our results provide a comprehensive picture on the magnetism in CrI3 and point to the possibility of engineering magnetic heterostructures within the same material.

12.
World J Clin Cases ; 7(21): 3463-3473, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31750329

RESUMO

BACKGROUND: Several studies have demonstrated the feasibility and effectiveness of using ultrasound elastography to assess liver tissue stiffness. Virtual touch imaging quantification (VTIQ) based on acoustic radiation force impulse imaging has been developed as a latest and noninvasive method for assessing liver stiffness in children. AIM: To determine the standard value in healthy children, and to identify possible factors that might influence the VTIQ measurement. METHODS: With the ethical approval, 202 children between 1 month and 15 years old were included in this study. None of them had any liver or systematic diseases. All children had a normal ultrasound scan and normal body mass index (BMI) range. The subjects were divided into four age and BMI groups. The effects of gender, age, liver lobe, measurement depth, and BMI on liver elasticity were investigated. RESULTS: A significant correlation was found between age and shear wave velocity (SWV) value. At measurement depths of 1.5 cm and 2.0 cm in the left lobe, there were significant differences among the age groups. SWV values were significantly negatively correlated with the measurement depth. Gender, liver lobe, and BMI showed no significant effect on the SWV values. Age and BMI may influence the quality of the elastogram. CONCLUSION: VTIQ is a noninvasive technique that is feasible to measure liver stiffness in children. The afore-mentioned velocity value obtained utilizing VTIQ method could be used as reference value for normal liver stiffness in children.

13.
Neurol Sci ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31754876

RESUMO

As a noninvasive technique, transcranial sonography (TCS) of substantia nigra (SN) has gradually showed its effectiveness not only in diagnosis but also in understanding clinical features of Parkinson's Disease (PD). This study aimed to further evaluate TCS for clinical diagnosis of PD, and to explore the association between sonographic manifestations and visual hallucinations (VH). A total of 226 subjects including 141 PD patients and 85 controls were recruited. All participants received TCS. A series of rating scales to evaluate motor and non-motor symptoms were performed in PD patients. Results showed that 172 subjects were successfully assessed by TCS. The area of SN was greater in PD patients than that in controls (P < 0.001). As receiver-operating characteristic (ROC) curve analysis showed, the best cutoff value for the larger SN echogenicity size was 23.5 mm2 (sensitivity 70.3%, specificity 77.0%). Patients with VH had larger SN area (P = 0.019), as well as higher Non-Motor Symptoms Scale (NMSS) scores (P = 0.018). Moreover, binary logistic regression analysis indicated that SN hyperechogenicity (odds ratio = 4.227, P = 0.012) and NMSS scores (odds ratio = 0.027, P = 0.042) could be the independent predictors for VH. In conclusion, TCS can be used as an auxiliary diagnostic tool for Parkinson's disease. Increased SN echogenicity is correlated with VH in Parkinson's disease, possibly because the brain stem is involved in the mechanism in the onset of VH. Further studies are needed to confirm these findings.

14.
Beilstein J Nanotechnol ; 10: 2031-2038, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31728252

RESUMO

We have investigated the thermoelectric properties of a pristine MoO3 monolayer and its defective structures with different oxygen vacancies using first-principles methods combined with Boltzmann transport theory. Our results show that the thermoelectric properties of the MoO3 monolayer exhibit an evident anisotropic behavior which is caused by the similar anisotropy of the electrical and thermal conductivity. The thermoelectric materials figure of merit (ZT) value along the x- and the y-axis is 0.72 and 0.08 at 300 K, respectively. Moreover, the creation of oxygen vacancies leads to a sharp peak near the Fermi level in the density of states. This proves to be an effective way to enhance the ZT values of the MoO3 monolayer. The increased ZT values can reach 0.84 (x-axis) and 0.12 (y-axis) at 300 K.

15.
Biomater Sci ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31728464

RESUMO

Prevention of bacterial infection and promotion of osseointegration are two important issues for titanium (Ti) implants in medical research. In addition, after a biofilm is formed on the surface of implants, the immune system and antibiotic therapy may fail. In this work, bio-functionalized titanium dioxide (TiO2)/molybdenum disulfide (MoS2)/polydopamine (PDA)/arginine-glycine-aspartic acid (RGD) nanorod arrays (NAs) are prepared on Ti implants to not only kill bacteria noninvasively upon co-irradiation of 660 nm visible light (VL) and 808 nm near infrared (NIR) light, but also promote the osteogenic activity simultaneously. Dual light irradiation triggers the TiO2/MoS2 NA to generate hyperthermia and reactive oxygen species (ROS) in 10 min. The synergistic effects of the generated hyperthermia and ROS increase the bacterial membrane permeability and bacteria are killed rapidly and efficiently in vitro and in vivo. The biofilm is also eradicated and RGD on the nanorods improves cell adhesion, proliferation, and osteogenic differentiation. The strategy described here for the design of bio-functionalized coatings on Ti implants has great clinical potential in orthopedics, dentistry, and other medical fields.

16.
J Hazard Mater ; 384: 121324, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31586921

RESUMO

Research on coal desulfurization is very important for economic, social, and environmentally sustainable development. In this study, three batches of shake flask experiments were conducted for coal bio-desulfurization using Acidithiobacillus ferrooxidans to explore the relationship between microbial nutrients (iron-free M9 K medium) supply and coal bio-desulfurization efficiency. The results showed that the removal rates of pyritic sulfur and total sulfur from coal effectively increased following reintroduction of coal into the filtrate from previous batch. The removal rates of pyritic sulfur and total sulfur were 55.6% and 10.0%, 77.1% and 16.1%, and 86.5% and 28.2%, respectively, in the three batch experiments without iron-free M9 K medium addition. In contrast, the removal rates of pyritic sulfur and total sulfur reached 87.5% and 28.2%, 89.1% and 31.6%, and 92.0% and 29.1%, respectively, in the three batch experiments with 6.7% iron-free M9 K medium addition. However, addition of excessive iron-free M9 K medium was detrimental to coal bio-desulfurization because of the synthesis of jarosite (MFe3(SO4)2(OH)6, M = K+, NH4+) and gypsum (CaSO4·2H2O), which further declined the pyritic sulfur bio-oxidation efficiency and total sulfur removal efficiency.

17.
MMWR Morb Mortal Wkly Rep ; 68(41): 928-933, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31622286

RESUMO

Each year, tobacco use is responsible for approximately 8 million deaths worldwide, including 7 million deaths among persons who use tobacco and 1.2 million deaths among nonsmokers exposed to secondhand smoke (SHS) (1). Approximately 80% of the 1.1 billion persons who smoke tobacco worldwide reside in low- and middle-income countries (2,3). The World Health Organization's (WHO's) Framework Convention on Tobacco Control (FCTC) provides the foundation for countries to implement and manage tobacco control through the MPOWER policy package,* which includes monitoring tobacco use, protecting persons from SHS, warning them about the danger of tobacco, and enforcing bans on tobacco advertising, promotion, or sponsorship (tobacco advertising) (4). CDC analyzed data from 11 countries that completed two or more rounds of the Global Adult Tobacco Survey (GATS) during 2008-2017. Tobacco use and tobacco-related behaviors that were assessed included current tobacco use, SHS exposure, thinking about quitting because of warning labels, and exposure to tobacco advertising. Across the assessed countries, the estimated percentage change in tobacco use from the first round to the most recent round ranged from -21.5% in Russia to 1.1% in Turkey. Estimated percentage change in SHS exposure ranged from -71.5% in Turkey to 72.9% in Thailand. Estimated percentage change in thinking about quitting because of warning labels ranged from 77.4% in India to -33.0% in Turkey. Estimated percentage change in exposure to tobacco advertising ranged from -66.1% in Russia to 44.2% in Thailand. Continued implementation and enforcement of proven tobacco control interventions and strategies at the country level, as outlined in MPOWER, can help reduce tobacco-related morbidity and mortality worldwide (3,5,6).


Assuntos
Saúde Global/estatística & dados numéricos , Uso de Tabaco/epidemiologia , Uso de Tabaco/psicologia , Adulto , Inquéritos Epidemiológicos , Humanos
18.
Chemistry ; 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31625216

RESUMO

The development of powerful and general methods to acquire ubiquitin (Ub) chains has prompted the deciphering of Ub-mediated processes. Herein, the cysteine-aminoethylation assisted chemical ubiquitination (CAACU) strategy is extended and improved to enable the efficient semi-synthesis of atypical Ub chain analogues and Ub-based probes. Combining the Cys aminoethylation and the auxiliary-mediated protein ligation, several linkage- and length-defined atypical Ub chains including di-Ubs, K27C-linked tri-Ub, K11/K48C-branched tri-Ub, and even the SUMOlated Ub are successfully prepared from recombinantly expressed starting materials at about a 9-20 mg L-1 expression level. In addition, the utility of this strategy is demonstrated with the synthesis of a novel non-hydrolyzable di-Ub PA probe, which may provide a new useful tool for the mechanistic studies of deubiquitinase (DUB) recognition.

19.
J Immunol Res ; 2019: 7371458, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31612152

RESUMO

To investigate the clinical features of parenchymal neuro-Behcet's disease (p-NBD), we retrospectively reviewed the medical records of 1009 BD patients admitted to Peking Union Medical College Hospital from 2000 to 2016. Forty-two patients (25 males and 17 females) with p-NBD and eighty-four age- and sex-matched BD patients without neurological involvement who were served as controls were enrolled. Neurological onset was concomitant with the onset of BD in six cases (14.3%). Pyramidal signs (50.0%) and headache (33.3%) were the most common manifestations. On MRI, the lesions were mainly in the midline structures and hyperintense in the T2-weighted image. The most common lesion was the brainstem (54.8%). Spinal cord involvement was observed in five cases, four of which with cervical cord involvement. Multifocal lesions were observed in 13 patients. Ocular involvement was more prevalent in p-NBD (35.7%) (P = 0.041, OR = 2.36, 95% CI = 1.03-5.44) compared with controls. All patients received corticosteroids and immunosuppressants, mainly cyclophosphamide (39/42). Six patients with severe/refractory condition received biological agents and achieved response measured by decreased Rankin score (P = 0.002). With a median follow-up of 28 months, 22 patients (61.1%) achieved clinical improvements, while 10 (27.8%) relapsed and 4 died (mortality rate 11.1%). p-NBD is a rare yet disabling and life-threatening complication of BD. Ocular involvement is a risk factor for p-NBD. Promptly aggressive treatment is essential for improving prognosis, and biological agents might be a promising approach for severe/refractory p-NBD.

20.
J Org Chem ; 84(22): 14861-14867, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31642325

RESUMO

Ubiquitin (Ub)-based fluorescent reagents are crucial to explore the activity of deubiquitinases (DUBs). Ub-Rho110-G is one of the preferred tools, whereas the current synthetic route is time-consuming. Here, we report a new semisynthetic strategy to produce Ub-Rho110-G through direct aminolysis of Boc-protected Ub-Mesna using bisglycyl-rhodamine 110. We also applied this strategy to synthesize active SUMO2-Rho110-G for the first time. Biochemical analysis demonstrated that semisynthetic Ub or SUMO-Rho110-G can be effectively used for the detection of the activity of DUBs or SUMO-specific enzymes.

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