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1.
J Clin Lab Anal ; : e23281, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32157743

RESUMO

BACKGROUND: Detection of hepatitis B virus (HBV) is vital for the diagnosis of hepatitis B infection. A novel test loop-mediated isothermal amplification (LAMP) has been successfully applied to detect various pathogens. However, the accuracy of LAMP in diagnosing HBV remains unclear. Therefore, in the present study, the accuracy of LAMP for HBV detection was evaluated systematically. METHODS: Embase, Cochrane Library, and PubMed databases were searched for studies using LAMP to detect HBV. Then, two researchers extracted data and assessed the quality of literature using the QUADAS-2 tool independently. I2 statistic and chi-square test were analyzed to investigate the heterogeneity, and Deek's funnel plot assessed the publication bias. The pooled sensitivity (SEN), specificity (SPE), positive LR (PLR), negative LR (NLR), diagnostic odds ratio (DOR), and 95% confidence intervals were displayed in forest plots. We calculated the area under the curve (AUC) to assess the overall efficiency of LAMP for HBV detection. RESULTS: A total of nine studies with 1298 samples were finally included in this evaluation. The pooled sensitivity and specificity of HBV detection were 0.91 (95% CI: 0.89 ~ 0.92) and 0.97 (95% CI: 0.94 ~ 0.99), respectively. The PLR, NLR, and DOR were 16.93 (95% CI: 6.15 ~ 46.55), 0.08 (95% CI: 0.05 ~ 0.14), and 397.57 (95% CI: 145.41 ~ 1087.07). Besides, the AUC was 0.9872, and Deek's plot suggested that there existed publication bias in the studies. CONCLUSION: Compared with PCR, LAMP is a simple, rapid, and effective assay to diagnose HBV. However, additional evidence is essential to confirm that LAMP can replace other methods in diagnosing HBV infection.

2.
Curr Biol ; 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32142700

RESUMO

Ancient Chinese poetry is constituted by structured language that deviates from ordinary language usage [1, 2]; its poetic genres impose unique combinatory constraints on linguistic elements [3]. How does the constrained poetic structure facilitate speech segmentation when common linguistic [4-8] and statistical cues [5, 9] are unreliable to listeners in poems? We generated artificial Jueju, which arguably has the most constrained structure in ancient Chinese poetry, and presented each poem twice as an isochronous sequence of syllables to native Mandarin speakers while conducting magnetoencephalography (MEG) recording. We found that listeners deployed their prior knowledge of Jueju to build the line structure and to establish the conceptual flow of Jueju. Unprecedentedly, we found a phase precession phenomenon indicating predictive processes of speech segmentation-the neural phase advanced faster after listeners acquired knowledge of incoming speech. The statistical co-occurrence of monosyllabic words in Jueju negatively correlated with speech segmentation, which provides an alternative perspective on how statistical cues facilitate speech segmentation. Our findings suggest that constrained poetic structures serve as a temporal map for listeners to group speech contents and to predict incoming speech signals. Listeners can parse speech streams by using not only grammatical and statistical cues but also their prior knowledge of the form of language. VIDEO ABSTRACT.

3.
Neuropsychologia ; 140: 107389, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32057939

RESUMO

Cognitive functions, for example speech processing, are distributed asymmetrically in the two hemispheres that mostly have homologous anatomical structures. Dichotic listening is a well-established paradigm to investigate hemispherical lateralization of speech. However, the mixed results of dichotic listening, especially when using tonal languages as stimuli, complicates the investigation of functional lateralization. We hypothesized that the inconsistent results in dichotic listening are due to an interaction in processing a mixture of acoustic and linguistic attributes that are differentially processed over the two hemispheres. In this study, a within-subject dichotic listening paradigm was designed, in which different levels of speech and linguistic information was incrementally included in different conditions that required the same tone identification task. A left ear advantage (LEA), in contrast with the commonly found right ear advantage (REA) in dichotic listening, was observed in the hummed tones condition, where only the slow frequency modulation of tones was included. However, when phonemic and lexical information was added in simple vowel tone conditions, the LEA became unstable. Furthermore, ear preference became balanced when phonological and lexical-semantic attributes were included in the consonant-vowel (CV), pseudo-word, and word conditions. Compared with the existing REA results that use complex vowel word tones, a complete pattern emerged gradually shifting from LEA to REA. These results support the hypothesis that an acoustic analysis of suprasegmental information of tones is preferably processed in the right hemisphere, but is influenced by phonological and lexical semantic processes residing in the left hemisphere. The ear preference in dichotic listening depends on the levels of speech and linguistic analysis and preferentially lateralizes across the different hemispheres. That is, the manifestation of functional lateralization depends on the integration of information across the two hemispheres.

4.
J Surg Res ; 249: 145-155, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31958599

RESUMO

BACKGROUND: Emerging evidence has linked autophagy to skin wound healing; however, the underlying cellular and molecular mechanisms remain poorly understood. The present study was designed to determine the role of autophagy in endothelial cell (EC)-mediated skin wound healing in mice. METHODS: Autophagy-related gene (Atg7) in mouse ECs was inactivated by the Cre-loxP system under the control of an EC-specific VE-Cadherin (Cdh5) promoter (Atg7EC-/- mice). Full-thickness skin wounds were created on the dorsum of wild-type (WT), Cdh5-Cre+, floxed Atg7 (Atg7F/F), and Atg7EC-/- mice. Autophagic activity was determined by autophagic flux assay in the primary culture of ECs isolated from these mice. The wound re-epithelialization and angiogenesis was examined by histological analyses. The angiogenic activity of ECs was evaluated by tube formation assay in vitro. EC proliferation was examined by a cell count CCK-8 kit. EC-originated intercellular communication with dermal fibroblasts and keratinocytes was assessed by measuring the effect of EC conditional medium on the growth of keratinocytes and fibroblasts. The levels of VEGF, EGF, bFGF in EC conditional medium were measured by ELISA. RESULTS: Autophagy deficiency in ECs markedly enhanced the re-epithelialization and the wound closure during skin wound healing. However, it has minimal impact on angiogenesis in the wounded skin. Notably, autophagy deficiency in ECs did not affect their proliferation and migration or angiogenic activity per se but enhanced the EC conditional medium-induced proliferation and migration of keratinocytes and fibroblasts. CONCLUSIONS: These results demonstrate for the first time an inhibitory role of autophagy in the EC-originated paracrine regulation of skin wound healing.

5.
J Asian Nat Prod Res ; 22(4): 353-358, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30835549

RESUMO

Twelve dihydrostilbenes (including five new analogues) were prepared by the Witting-Hornor reaction from appropriate aromatic aldehydes and phosphonate esters, followed by hydrogenation in five steps. The in vitro inhibition activity against human neutrophil elastase (HNE) of these dihydrostilbenes was evaluated, and three 1,2-dihydroxylated dihydrostilbenes (6b, 6j, and 6l) exhibited stronger inhibitory activity against HNE than other analogues.


Assuntos
Elastase de Leucócito , Humanos , Estrutura Molecular
6.
J Asian Nat Prod Res ; 22(2): 144-152, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30526081

RESUMO

Two oleanane-type triterpenoid saponins named pedunsaponin D (1) and pedunsaponin E (2) were isolated from the roots of Pueraria peduncularis. The structures of the new compounds were elucidated based on chemical and physicochemical evidence as follows: pedunsaponin D, 3-O-ß-glucopyranosyl-(1-3)-ß-glucuronopyranosyl-3ß,15α,23α-trihydroxy-11,13(18)-oleanadien-16-one (1); pedunsaponin E, 3-O-ß-glucopyranosyl-(1-2)-ß-glucopy ranosyl(1-2)[ß-glucopyranosyl(1-3)-ß-glucuronopyranosyl]-3ß-hydroxy-16-oxoolean-12-en-30-oic acid (2). The two compounds showed moderate molluscicidal activity.[Formula: see text].


Assuntos
Pueraria , Saponinas , Triterpenos , Estrutura Molecular , Raízes de Plantas
7.
Food Funct ; 11(1): 561-571, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31850465

RESUMO

Dietary consumption of flavonoids correlated positively with lower risk of cardiovascular disease. However, the precise roles of flavonoids from the blossoms of Citrus aurantium Linn variant amara Engl (CAVA) in atherosclerosis (AS) are still poorly understood. This study aimed to find novel flavonoid-type skeletons with protection against AS. Total flavonoids (CAVAF), homoeriodictyol (HE) and hesperetin-7-O-ß-d-glucopyranoside (HG) were isolated from the blossoms of Citrus aurantium Linn variant amara Engl. by chromatography. Their suppressive effects on lipopolysaccharide (LPS)-induced inflammatory responses and ox-LDL-induced foam cell formation were systematically and comparatively investigated using macrophage RAW264.7 cells. HE was more powerful than HG in inhibiting LPS-induced production of nitric oxide (NO), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1ß) and gene expression in RAW264.7 cells. HE and HG showed different responses to extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinases (JNK), P38, P65, IκBα, IκKα/ß phosphorylation, and nuclear factor-kappa B (NF-κB) nuclear translocation. HE and HG also differentially decreased oxidized low-density lipoprotein (ox-LDL)-induced foam cell formation by regulating peroxisome proliferator-activated receptor-gamma (PPARγ), phospholipid ATP-binding cassette transporter A1 (ABCA1), phospholipid ATP-binding cassette transporter G1 (ABCG1), scavenger receptor class B type I (SRB1), scavenger receptor class A type I (SRA1) and cluster of differentiation 36 (CD36) expression at gene and protein levels in RAW264.7 cells. HG showed weaker potential than HE in preventing AS development. Their chemical differences might partially explain the discrepancy in their bioactivity. In conclusion, HE and HG might be developed into novel therapeutic agents against inflammation and AS-associated diseases.

8.
Curr Mol Med ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31804167

RESUMO

INTRODUCTION: Pain is one of the most common symptoms in clinical. This review is to describe researches on herbs and their active ingredients in treating pain and provide valuable reference for the development and utilization of analgesic traditional Chinese medicine (TCM). Areas covered: The literature search was performed from 1995 to October 2016, covering the relevant literatures that concern the treatment of pain with TCM. Active ingredients extracted from TCM with analgesic activity are summarized and classified into six categories, including polysaccharides, saponins, alkaloids, flavonoids, terpenoids and other constituents. Expert opinions: There are two pathways constituting the analgesic mechanisms of TCM: through the central nervous system and through the peripheral nervous system. The former pathway includes increasing the content of endogenous analgesic substances like opiate peptide, cutting down the second messenger of neurotransmitter like nitric oxide (NO), reducing the content of prostaglandin E2 (PGE2) in brain tissue, blocking the central calcium channel, reducing excitatory amino acids in brain tissue, inhibiting their receptors and raising the content of the central 5-hydroxytryptamine (5-HT). The latter one usually contains the decrease in secretion of peripheral algogenic substances, the induction of pain-sensitive substances and the accumulation of local algogenic substance, the increase in release of peripheral endogenous analgesia materials and the regulation of c-Fos gene (immediate early gene).

9.
IEEE Trans Cybern ; 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31841431

RESUMO

Current hashing-based image retrieval methods mostly assume that the database of images is static. However, this assumption is not true in cases where the databases are constantly updated (e.g., on the Internet) and there exists the problem of concept drift. The online (also known as incremental) hashing methods have been proposed recently for image retrieval where the database is not static. However, they have not considered the concept drift problem. Moreover, they update hash functions dynamically by generating new hash codes for all accumulated data over time which is clearly uneconomical. In order to solve these two problems, concept preserving hashing (CPH) is proposed. In contrast to the existing methods, CPH preserves the original concept, that is, the set of hash codes representing a concept is preserved over time, by learning a new set of hash functions to yield the same set of hash codes for images (old and new) of a concept. The objective function of CPH learning consists of three components: 1) isomorphic similarity; 2) hash codes partition balancing; and 3) heterogeneous similarity fitness. The experimental results on 11 concept drift scenarios show that CPH yields better retrieval precisions than the existing methods and does not need to update hash codes of previously stored images.

10.
Huan Jing Ke Xue ; 40(11): 4932-4943, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854559

RESUMO

Shibalianwei is a large constructed wetland formed at the estuary of the Nanfei River adjoining Lake Chaohu. To investigate the distribution and pollution characteristics of nutrients and heavy metals in surface sediments of Shibalianwei Wetland, sediment samples were collected from 72 sites in July 2018. The source of the pollution was analyzed. Our results showed that the average contents of total nitrogen (TN), total phosphorus (TP), and organic matter (OM) in surface sediments of Shibalianwei were 2108.87 mg·kg-1, 1448.82 mg·kg-1, and 86.2 g·kg-1, respectively; in the external water system of the wetland, they were 2305.81 mg·kg-1, 1268.46 mg·kg-1, and 59.9 g·kg-1, respectively. The average contents of heavy metals of Mn, Cr, Cu, Pb, Cd, As, and Hg in Shibalianwei were 462.58, 42.12, 21.69, 18.05, 0.63, 5.67, and 0.059 mg·kg-1, respectively; in the external water bodies, they were 381.61, 36.85, 24.74, 30.70, 2.49, 6.47, and 0.035 mg·kg-1, respectively. In the assessments of nutrient pollution of internal water bodies of Shibalianwei, TN was at mild to moderate pollution levels, TP was at a heavy pollution level, and the comprehensive pollution index (FF) indicated that nutrients in Shibalianwei were at moderate to heavy pollution levels. The assessment results of the organic pollution index (OI) were consistent with the FF. The potential ecological risk assessments of heavy metals showed that both Cd and Hg reached certain ecological risks, which were indicated by RI and Eri. For external water bodies, the nutrient levels were also high and heavy metal pollution was relatively serious, indicating high ecological risks.

11.
Opt Express ; 27(21): 30517-30529, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684298

RESUMO

Injecting radio frequency (RF) white noise to the current driving of the laser can broaden the laser emission linewidth and efficiently suppress cavity-mode noise in off-axis integrated cavity output spectroscopy (OA-ICOS). The effect of the injected RF noise level on the cavity-mode noise and the deformation of the absorption line shape in off-axis integrated cavity output spectroscopy (OA-ICOS) with a distributed feedback laser (DFB) at 1.65 µm were investigated. We measured methane at different concentrations between 0.1 ppmv and 2 ppmv associated with a -20 dBm RF noise injection. A linear spectral response of the intensity of the cavity output spectra with the CH4 concentration was observed. A threefold improvement in the detection limit was achieved compared to unperturbed OA-ICOS. The response time of the improved OA-ICOS system is about 30 s and the minimum detectable concentration (MDC) of CH4 is 7.6 ppbv, which corresponds to a minimum detectable fractional absorption scaled to the path length of 7.3 × 10-10 cm-1. The noise equivalent absorption sensitivity of the system is 5.51 × 10-9 cm-1Hz-1/2.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31725396

RESUMO

The probabilistic classification vector machine (PCVM) synthesizes the advantages of both the support vector machine and the relevant vector machine, delivering a sparse Bayesian solution to classification problems. However, the PCVM is currently only applicable to binary cases. Extending the PCVM to multiclass cases via heuristic voting strategies such as one-vs-rest or one-vs-one often results in a dilemma where classifiers make contradictory predictions, and those strategies might lose the benefits of probabilistic outputs. To overcome this problem, we extend the PCVM and propose a multiclass PCVM (mPCVM). Two learning algorithms, i.e., one top-down algorithm and one bottom-up algorithm, have been implemented in the mPCVM. The top-down algorithm obtains the maximum ita posteriori (MAP) point estimates of the parameters based on an expectation-maximization algorithm, and the bottom-up algorithm is an incremental paradigm by maximizing the marginal likelihood. The superior performance of the mPCVMs, especially when the investigated problem has a large number of classes, is extensively evaluated on the synthetic and benchmark data sets.

13.
Sci Rep ; 9(1): 16529, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712569

RESUMO

The leaves of many plants are red during particular stages of their lives, but the adaptive significance of leaf colouration is not yet clearly understood. In order to reveal whether anthocyanins play a similar role (i.e. antioxidants) in different seasonal contexts, this study investigated species with red young leaves in the subtropical forest of Dinghushan biosphere reserve (South China) during summer and winter and compared group leaf characteristics between the two seasons. Of 62 total species, 33 exhibited red young leaves in summer only, 6 in winter only, and 23 in both seasons. The anthocyanins extracted from most of these species had an absorption peak at ~530 nm. Frequency distribution analysis showed that the species containing anthocyanins at levels ranging from 0.02 to 0.04 µmol cm-2 occurred most frequently in summer or winter. Based on conditional grouping of the species, no significant variation was observed in the average anthocyanin contents and antioxidant abilities between summer and winter; the flavonoid content in summer was 2-fold that in winter, whereas the anthocyanin:flavonoid ratio in summer was only half that in winter. Moreover, a positive correlation between anthocyanins and flavonoids was found in summer. Therefore, it is less likely for anthocyanins to serve as antioxidants in summer than winter, because such a function in summer leaves is readily replaced by other flavonoids.

14.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(4): 362-367, 2019 Sep 19.
Artigo em Chinês | MEDLINE | ID: mdl-31612669

RESUMO

OBJECTIVE: To compare the difference of fertility of Biomphalaria glabrata snails between self-fertilization and cross-fertilization and to observe the circadian rhythm of laying eggs, the effect of light on laying eggs and the tolerance of the snail to water and food deficiency, so as to provide the evidence for control and elimination of B. glabrata snails in the field. METHODS: Under laboratory conditions, a single B. glabrata egg for self-fertilization was separated and hatched individually, and young snails were raised in different plastic boxes individually. The eggs for cross-fertilization were hatched and the young snails were fed in the same plastic box. The ability of spawn, the development of the eggs, and the number of snails growing from young to adult snails were compared between the self-fertilization and cross-fertilization. The snails were in the water under four environments, all day illumination, all day without illumination, daytime lighting and night without illumination, and daytime without illumination but night lighting. The eggs were collected and counted daily. The circadian rhythm of spawn and the effect of illumination on spawn were observed. The adult snails were divided into 6 groups and exposed to the environments with relative humidity of 0, 65%, 87% and 100%, respectively. The survival rates of the adult snails exposed to the different environments after different time were observed. The adult snails were placed at 25 °C in the oven to remove water content from the soft body of snails. When the dehydration rates of the soft bodies achieved 10%, 20%, 30%, 40%, 50%, 52%, 55%, 57%, 60%, and 70% respectively, the survival rates of the adult snails exposed to the oven were observed. RESULTS: In the 25 °C water, the average laying egg number for 15 days per snail was (8.77 ± 16.92) eggs/snail in the self-fertilization snail. The average laying egg number for 15 days per snail was (149.71 ± 142.28) eggs/snail in the cross-fertilization snails. There was a significant difference between the self-fertilization snail and cross-fertilization snail (t = 0.999 999, P < 0.01). The hatching rate and reproductive maturation rate of the self-fertilization snails and cross-fertilization snails were 50.1% and 78.9%, and 19.3% and 3.8%, respectively, There was a significant difference (the hatching rate: χ2 = 18.18, P < 0.01, the reproductive maturation rate: χ2 = 11.83, P < 0.01) . In the natural environment of daytime with illumination and nighttime with darkness, the amount of laying 20 eggs of B. glabrata snail was (944.07 ± 392.53) eggs/day during a whole day, among them the amount of laying eggs during daytime account for 10.1% and the amount of laying eggs during nighttime account for 89.9%, and the laying egg was given priority to with the night. The above results suggested that the dark environment was conducive to B. glabrata snails to lay eggs. The above results suggested that light can promote the increase of spawning of B. glabrata. When B. glabrata was exposed to the environments with the relative humidity of 0, 65%, 87% and 100% at 25 °C, respectively, and the longest survival times of snails were 7, 70, 150 d and 100 d, respectively. In the 25 °C water, the snails could survive for 50 days without food. The adult snails were placed at 25 °C in the oven to remove water content from the soft body of snails. When the dehydration rates of the soft bodies achieved 10%, 20%, 30%, 40%, 50%, 52%, 55%, 57%, 60%, and 70% respectively, the survival rates of the adult snails exposed to the oven were 100%, 100%, 100%, 100%, 70%, 30%, 0, 0, 0 and 0, respectively. CONCLUSIONS: B. glabrata can achieve the reproductive process by cross-fertilization or self-fertilization. There is a significant difference in reproductive ability between the cross-fertilization snail and self-fertilization snail, cross-fertilization is stronger than self-fertilization, but the rate of reproduction in the self-fertilization is higher than that in the cross-fertilization. It is indicated that B. glabrata that survive after the dry season plays an important role in the maintenance of local snail populations and transmission of schistosomiasis mansoni.


Assuntos
Biomphalaria , Interações Hospedeiro-Parasita , Schistosoma mansoni , Animais , Biomphalaria/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Estágios do Ciclo de Vida/fisiologia , Reprodução , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/transmissão , Estações do Ano
15.
IUCrJ ; 6(Pt 5): 968-983, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31576229

RESUMO

As is well known, polymers commonly form lamellar crystals, and these assemble further into lamellar stacks and spherulites during quiescent crystallization. Fifty years ago, Vonk and Kortleve constructed the classical small-angle X-ray scattering theory (SAXS) for a lamellar system, in which it was assumed that the lamellar stack had an infinite lateral size [Vonk & Kortleve (1967 ▸), Kolloid Z. Z. Polym. 220, 19-24]. Under this assumption, only crystal planes satisfying the Bragg condition can form strong scattering, and the scattering from the lamellar stack arises from the difference between the scattering intensities in the amorphous and crystalline layers, induced by the incident X-ray beam. This assumption is now deemed unreasonable. In a real polymer spherulite, the lamellar crystal commonly has dimensions of only a few hundred nanometres. At such a limited lateral size, lamellar stacks in a broad orientation have similar scattering, so interference between these lamellar stacks must be considered. Scattering from lamellar stacks parallel to the incident X-ray beam also needs to be considered when total reflection occurs. In this study, various scattering contributions from lamellar stacks in a spherulite are determined. It is found that, for a limited lateral size, the scattering induced by the incident X-ray beam is not the main origin of SAXS. It forms double peaks, which are not observed in real scattering because of destructive interference between the lamellar stacks. The scattering induced by the evanescent wave is the main origin. It can form a similar interference pattern to that observed in a real SAXS measurement: a Guinier region in the small-q range, a signal region in the intermediate-q range and a Porod region in the high-q range. It is estimated that, to avoid destructive interference, the lateral size needs to be greater than 11 µm, which cannot be satisfied in a real lamellar system. Therefore, SAXS in a real polymer system arises largely from the scattering induced by the evanescent wave. Evidence for the existence of the evanescent wave was identified in the scattering of isotactic polypropyl-ene. This study corrects a long-term misunderstanding of SAXS in a polymer lamellar system.

16.
Cancer Manag Res ; 11: 8911-8921, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632151

RESUMO

Purpose: Metadherin (MTDH), as an oncogene, is associated with metastasis and poor prognosis. This study investigated MTDH expressions and development of gastric cancer (GC) cell phenotypes and the contribution of MTDH to epithelial-mesenchymal transition (EMT). Patients and methods: MTDH expression was assayed in human GC cell lines and tumor tissue from 92 GC patients. Functional experiments were performed to characterize MTDH activity. Expressions of EMT-related proteins (vimentin and E-cadherin), phosphorylated ß-catenin and ß-catenin were assayed by immunohistochemistry, Western blotting, immunofluorescence, and co-immunoprecipitation, respectively. Results: MTDH expressions were higher in GC tissue than that in gastric mucosa from the same patient. MTDH overexpression was correlated with metastasis and enhanced malignant GC phenotypes, i.e., proliferation, migration, invasiveness, and chemoresistance. MTDH overexpression was associated with expressions of vimentin, E-cadherin and cancer stem-cell biomarkers including CD44, CD133, and Oct4. MTDH complexed with ß-catenin and decreased phosphorylated ß-catenin levels to facilitate ß-catenin translocation into the nucleus and expressions of downstream genes. Conclusion: MTDH overexpression in GC cells is associated with EMT and development of cancer stem cell malignant phenotypes and affects the subcellular translocation of ß-catenin. The results warrant investigation of the prognostic value of MTDH in GC and as a therapeutic target.

17.
Biosci Rep ; 39(10)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31537628

RESUMO

BACKGROUND: Candida is a fungus that causes various types of candidemia, which is the fourth major infectious disease of the blood system. MALDI-TOF-MS is a simple and rapid detection instrument. The aim of the present study was to verify the accuracy of MALDI-TOF-MS in detecting Candida. METHOD: A pooled analysis of articles on MALDI-TOF-MS for diagnosis of candidemia was performed. The quality of original research was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) guidelines. Stata 12.0 software was used to merge the correct identification rates of Candida and Candida subspecies and obtain pooled sensitivity and specificity of the diagnostic methods. Heterogeneity was found in the subgroup analysis of the included articles. Hence, we explored the factors causing the heterogeneity and its impact on the overall situation. Sensitivity analysis was used to examine the effect of Candida level on total response. Egger's test was used to evaluate the publication bias of the included articles. RESULTS: A total of 16 articles in Pubmed, 79 articles in Embase, 1 article in Cochrane Library, 30 articles in Web of Science and 3 from other sources were identified, of which 10 articles were included based on the inclusion and exclusion criteria. The overall identification accuracy was 100%. CONCLUSION: The accuracy of MALDI-TOF-MS for the identification of Candida was 100%. Further research is necessary to determine whether MALDI-TOF-MS can be used as a clinical diagnostic standard for the identification of Candida.

18.
Arch Med Sci Atheroscler Dis ; 4: e191-e195, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31538123

RESUMO

Introduction: Nonalcoholic fatty liver disease (NAFLD) is seen commonly in patients with obesity, but there are many non-obese people who also have NAFLD, which we call lean NAFLD. The objective of this study is to compare the characters of lean and obese NAFLD individuals aimed to better understand the pathogenesis of NAFLD. Material and methods: A total of 496 NAFLD cases (history of alcohol consumption, medication used within the last 3 months, hepatitis virus infection, autoimmune or hereditary liver disease were excluded), divided into an obese (body mass index (BMI) ≥ 25 kg/m2) NAFLD group (n = 395) and lean (BMI < 25 kg/m2) NAFLD group (n = 101), were investigated. Gender, age, alanine aminotransferase, triglycerides, cholesterol, and the blood glucose were compared between the two groups. Results: A male-dominated discrepancy of gender distribution was more evident in obese NAFLD group. Elevated alanine amonotransferase was more common in the obese NAFLD group. 50-59 years was the peak age of both lean and obese NAFLD groups. Normal triglycerides (TG) patients were more common in the lean NAFLD group, while the proportion of elevated TG patients was higher in the obese NAFLD group. No statistically significant difference in the proportion of elevated cholesterol patients was found between the two groups. In the lean NAFLD group, the proportion of females was higher in the normal fasting glucose group. Conclusions: Sexual dimorphism exists in lean NAFLD patients, but this trend was most pronounced during the age range 40-49 years and disappeared after entering the 50-59-year-old age range. In lean NAFLD patients, normal levels of TG and blood glucose were more common, and occurrence of non-alcoholic steatohepatitis was less common than among obese NAFLD.

19.
Eur J Med Chem ; 182: 111645, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31494472

RESUMO

As our research focus on anticancer drugs, two series of novel derivatives of Flexicaulin A (FA), an ent-kaurene diterpene, condensation with amino acid trifluoroacetate were synthesized, and their anti-proliferative activity against four human cancer cell lines (TE-1, MCF-7, A549 and MGC-803) were evaluated. Compared with FA, the anticancer activity and solubility of most derivatives were significantly improved. Among them, compound 6d had the best activity, and its IC50 value against Esophageal cancer cells (TE-1) was up to 0.75 µM. Subsequent cellular mechanism studies showed that compound 6d could inhibit the proliferation of cancer cells, the formation of cell colonies, and increase the level of ROS on TE-1 cells. In addition, 6d could up-regulate the expressions of SAPK/JNK pathway-associated proteins (p-ASK1, p-MKK4 and p-JNK) and pro-apoptotic proteins (Bak, Bad and Noxa), remarkably increase the ratio of Bax to Bcl-2 and activate Cleaved Caspase-3/9/PARP. These results indicate that compound 6d induces apoptosis through the ROS/JNK/Bcl-2 pathway and holds promising potential as an anti-proliferative agent.


Assuntos
Aminoácidos/farmacologia , Antineoplásicos/farmacologia , Diterpenos de Caurano/farmacologia , Ácido Trifluoracético/farmacologia , Aminoácidos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Diterpenos de Caurano/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Ácido Trifluoracético/química , Células Tumorais Cultivadas
20.
Insects ; 10(9)2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31484469

RESUMO

Intrapuparial development is a special pattern of metamorphosis in cyclorrhaphous flies, in which the pupa forms in an opaque, barrel-like puparium. This has been well studied in forensic insects for age estimations. In this study, the intrapuparial development of a quarantine agricultural pest, Bactrocera dorsalis (Hendel), was studied under a constant temperature of 27 ± 1 °C and 70 ± 5% relative humidity. Results showed that intrapuparial development could be divided into five stages: Larval-pupal apolysis, cryptocephalic pupa, phanerocephalic pupa, pharate adult, and emergent adult. It lays a morphology-based foundation for molecular mechanism studies and enhances the understanding of the physiological basis for changes in intrapuparial development. More importantly, the chronology of intrapuparial development can be used to predict the emergence time of tephritid flies, indicating when to spray insecticides to control these phytophagous agricultural pests. This may be an effective approach to reduce the use of insecticides and slow down the evolution of insecticidal resistance.

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