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1.
Biomed Pharmacother ; 121: 109552, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31715370

RESUMO

Rhodiola rosea L., a worldwide botanical adaptogen, has been confirmed to possess protective effects of inflammatory injury for many diseases, including cardiovascular diseases, neurodegenerative diseases, diabetes, sepsis, and cancer. This paper is to review the recent clinical and experimental researches about the anti-inflammatory effects and the related mechanisms of Rhodiola rosea L. extracts, preparations, and the active compounds. From the collected information reviewed, this paper will provide the theoretical basis for its clinical application, and provide the evidences or guidance for future studies and medicinal exploitations of Rhodiola rosea L.

2.
Nat Commun ; 10(1): 5002, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676820

RESUMO

Metal-organic frameworks (MOFs) have recently garnered consideration as an attractive solid substrate because the highly tunable MOF framework can not only serve as an inert host but also enhance the selectivity, stability, and/or activity of the enzymes. Herein, we demonstrate the advantages of using a mechanochemical strategy to encapsulate enzymes into robust MOFs. A range of enzymes, namely ß-glucosidase, invertase, ß-galactosidase, and catalase, are encapsulated in ZIF-8, UiO-66-NH2, or Zn-MOF-74 via a ball milling process. The solid-state mechanochemical strategy is rapid and minimizes the use of organic solvents and strong acids during synthesis, allowing the encapsulation of enzymes into three prototypical robust MOFs while maintaining enzymatic biological activity. The activity of encapsulated enzyme is demonstrated and shows increased resistance to proteases, even under acidic conditions. This work represents a step toward the creation of a suite of biomolecule-in-MOF composites for application in a variety of industrial processes.

3.
Lasers Med Sci ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31691054

RESUMO

The objective of this study was to evaluate the clinical attachment level (CAL) gain of Er:YAG, Er,Cr; YSGG, Nd:YAG; and diode laser (DL) as monotherapy or adjunctive to scaling and root planing (SRP) of chronic periodontitis by network meta-analysis (NMA). Randomized controlled clinical trials (RCTs) about lasers applied in SRP of chronic periodontitis were searched from PubMed, Cochrane Library, Web of Science, Ovid, Science Direct, Wan Fang, and China National Knowledge Infrastructure (CNKI) databases up to September 2018 and from references of selected full-texts and related reviews. Standard mean differences and 95% confidence intervals were counted for CAL gain. The random effects NMA were performed in STATA software. There were 25 RCTs about CAL gain at 3 and/or 6 months after lasers were applied in SRP. No inconsistency was detected. Er:YAG as monotherapy gained significantly more CAL at 3 months than did SRP; no significant differences were detected among other comparisons. In terms of CAL gain at 3 months, the ranking result from best to worst was as follows: Er:YAG as monotherapy, DL adjunctive to SRP, Er:YAG adjunctive to SRP, Er,Cr;YSGG as monotherapy, Nd:YAG adjunctive to SRP, and SRP. In terms of CAL gain at 6 months, the ranking result from best to worst was as follows: DL adjunctive to SRP, Nd:YAG adjunctive to SRP, SRP, Er:YAG adjunctive to SRP, and Er:YAG as monotherapy. Laser-assisted periodontal treatment could be superior to SRP alone and could serve as a good adjunctive treatment tool.

4.
Asian J Surg ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31706922

RESUMO

BACKGROUND: Endoscopic submucosal dissection (ESD) has gained more popularity in the treatment of early gastric cancer (EGC). Although there is a lack of confirmed evidence for the feasibility of ESD for undifferentiated EGC. The aim of the study was to investigate the feasibility of ESD with expanded indications for undifferentiated EGC patients. METHODS: Data from patients with undifferentiated EGC (including signet-ring cell carcinoma, mucinous adenocarcinoma, mixed adenocarcinoma, and poorly differentiated adenocarcinoma) who underwent radical surgical resection were retrospectively reviewed. The relationship between the clinical parameters and the incidence of lymph node metastasis (LNM) was investigated. RESULTS: A total of 517 patients were included in this study. The results showed that LNM was significantly associated with ulceration, tumor size, depth of invasion, lymphatic invasion, vascular invasion, and perineural invasion. Multivariate stepwise logistic regression analysis revealed that tumor size (OR = 1.61, 95% CI = 1.03-2.52, P = 0.0367), depth of tumor invasion (OR = 2.77, 95% CI = 1.66-4.63, P = 0.0001), and lymphatic invasion (OR = 14.74, 95% CI = 1.58-137.36, P = 0.0182) were independent risk factors for LNM. In the patients who would be included under the new proposed guidelines for ESD, including men with mucosal tumors ≤2 cm and without ulceration or lymphatic or venous infiltration, LNM was present in 11.9% (14/118). CONCLUSION: Caution to be exercised in expanding application of ESD should be carefully weighed in undifferentiated EGC.

5.
Biotechnol Lett ; 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31781926

RESUMO

OBJECTIVES: Developing a counterselective system for efficient markerless gene deletions in biocontrol strain P. protegens Pf-5. RESULTS: We successfully implemented a markerless deletion of upp in Pf-5 to obtain the 5-FU resistant strain Pf5139. With this strain, we performed markerless gene deletions for each component of Gac/Rsm system and a 17 kb DNA fragment with the deletion ratio of 20 to 50%, and efficiently constructed a strain with triple deletions based on the suicide plasmid pJQ200UPP. In addition, there is no obvious connection between the deleted fragment length and the deletion ratio. CONCLUSION: The upp-based counterselective system in this study is efficient and valuable for markerless gene deletions in Pf-5, indicating that it has great potential in the study of gene function and in the application of genome reduction for Pseudomonas strains.

6.
Teach Learn Med ; : 1-9, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31755318

RESUMO

Phenomenon: China is a relatively homogenous nation where the majority of people are Han Chinese. In recent years, a large number of international students have begun to study medicine in China. Due to the privacy and intimacy associated with obstetrical and gynecological diseases, Chinese women's acceptance toward international students' involvement in their care has not been reported thus far. This survey aims (1) to determine Chinese women's attitudes toward both Chinese and international medical student involvements in obstetrical and gynecological outpatient departments and (2) to investigate possible reasons, if any, for their rejection of the medical students. Approach: We conducted a cross-sectional survey study using a locally-developed questionnaire. The survey was conducted in the obstetrical and gynecological outpatient department of a tertiary hospital in a Chinese harbor city. We surveyed 600 patients for their attitudes towards the involvement of four groups of medical student in clinical practice: Chinese female, International female, Chinese male, and International male. Among the returned questionnaires, 501 satisfied the criteria for analysis. Findings: Patient's acceptance rates of the four groups of students (Chinese female, International female, Chinese male, and International male) were 59.7%, 55.9%, 32.1%, and 25.9%, respectively. Analysis revealed that language barriers and lack of friendliness were the two main reasons leading to patients' low acceptance rates of international students. Insights: Obstetrical and gynecological patients are more likely to accept female students over male students, regardless of their nationality, however International male students receive the least acceptance. For international students, improving their Chinese language skills and using more friendly expressions may facilitate their practice in China.

7.
Insect Biochem Mol Biol ; : 103279, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31756435

RESUMO

In the present study, we demonstrated that bombyxin, an insect insulin-like peptide, modulated ecdysteroidogenesis in Bombyx mori prothoracic glands (PGs) through redox signaling. Our results showed that bombyxin treatment resulted in a transient increase in intracellular reactive oxygen species (ROS) concentration, as measured using 2',7'-dichlorofluorescin diacetate (DCFDA), an oxidation-sensitive fluorescent probe. The antioxidant N-acetylcysteine (NAC) abolished the bombyxin-induced increase in fluorescence in Bombyx PGs. Furthermore, bombyxin-induced ROS production was inhibited by mitochondrial oxidative phosphorylation inhibitors (rotenone and antimycin A), indicating mitochondria-mediated ROS production. The stimulation of ROS production in response to bombyxin appears to undergo development-specific changes. We further investigated the action mechanism of bombyxin-stimulated ROS signaling. Results showed that in the presence of either NAC, rotenone, or antimycin A, bombyxin-stimulated phosphorylation of insulin receptor, Akt, and 4E-binding protein (4E-BP) was blocked and bombyxin-stimulated ecdysteroidogenesis in PGs was greatly inhibited. From these results, we conclude that ROS signaling appears to be involved in bombyxin-stimulated ecdysteroidogenesis of PGs in B. mori by modulating the phosphorylation of insulin receptor, Akt, and 4E-BP. To our knowledge, this is the first demonstration of redox regulation in insulin signaling in an insect system.

8.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(4): 326-330, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31701716

RESUMO

OBJECTIVE: To investigate the effects of different intensity intermittent exercise on the body function of obese rats, and to provide basis for the prevention and treatment of obesity. METHODS: Eighty SD rats were randomly divided into normal diet group (n=20) and high-fat diet group (n=60). After adaptive feeding for 8 weeks, 8 normal diet rats and 32 high-fat obese rats were selected for follow-up experiments. The experimental rats were randomly divided into 5 groups (n=8): control diet-sedentary (CS),with ordinary feed and without any exercise; high diet-sedentary (HS), with high-fat feed feeding and without any exercise; high diet-continual exercise(HC), 60 min/day,5 days/week with 6 weeks; high diet-long time-low frequency interval exercise(HLL), 30 min/time,twice/day (intermittent 6 h), 5 days/week with 6 weeks; high diet-short time-high frequency interval exercise(HSH), 20 min/ time, 3 times/d (intermittent 3 h), 5 days/week with 6 weeks. The training intensity of rats in each exercise group was 25 m/min. After 6 weeks, rats in each groups were weighed, and resting metabolic rate(RMR), fasting blood glucose(FBG), triglyceride(TG) and other biochemical indexes were detected, and fat and muscle weight were measured. RESULTS: Before experiment, there were no significant differences in RMR, FBG and TG in each groups(P>0.05).The body weight of HSH, HLL, HC and HS groups was higher than that of CS group (P<0.05). After the experiment, RMR of the HSH,HLL and HC groups was significantly higher than that of HS and CS groups (P<0.05), but without significant difference among the HSH,HLL and HC groups (P>0.05).The body weight of HSH, HLL and HC groups was significantly lower than that of HS group (P<0.05), but the three groups was not significant (P>0.05); perirenal fat(PF), idymis fat(EF), perirenal fat/weight(PF/W) and epididymis fat/weight(EF/W) of HSH, HLL, HC group were significantly lower than those of HS group (P<0.01), while there was no statistical difference among the three groups (P>0.05). There was no significant difference in gastrocnemius(GM) and quadricep(QF) of each group (P>0.05), gastrocnemius/weight(GM/W) and quadriceps/weight (QF/W) in HSH,HLL and HC groups were higher than those of HS group (P<0.05),while there was no significant difference among HSH,HLL and HC groups (P>0.05);FEB,TG of HSH,HLL,HC group were lower than those of CS and HS group (P<0.05),but the difference with HS group was more significant (P<0.01),there was no significant difference among training groups(P>0.05). CONCLUSION: 6 weeks of intermittent exercise of different intensity had a good intervention effect on the body composition of obese rats, and high diet-short time-high frequency interval exercise (HSH) may be more effective.


Assuntos
Composição Corporal , Obesidade/terapia , Condicionamento Físico Animal , Animais , Peso Corporal , Dieta Hiperlipídica , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
9.
Phytochemistry ; 170: 112198, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31765875

RESUMO

Fungal endophytes from plants are an important source for discovery of novel bioactive natural products. In this study, five undescribed harziane diterpenoids with a 4/7/5/6 tetracyclic scaffold, harzianols F‒J and three known derivatives, were obtained from the liquid fermentation of an endophytic fungus Trichoderma atroviride B7, which was isolated from the healthy flower of a Lamiaceae plant Colquhounia coccinea var. mollis. Their structures were elucidated by comprehensive spectroscopic analyses and X-ray crystallographic diffraction in the case of harzianol F. Harzianol I exhibited significant antibacterial effect against the growth of Staphylococcus aureus (EC50 = 7.7 ± 0.8 µg/mL), Bacillus subtilis (EC50 = 7.7 ± 1.0 µg/mL), and Micrococcus luteus (EC50 = 9.9 ± 1.5 µg/mL). Meanwhile, cytotoxic activity of harzianol I against three cancer cell lines was also observed. A plausible biosynthetic pathway for harziane diterpenoids was proposed.

10.
Bull Environ Contam Toxicol ; 103(6): 789-795, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31605158

RESUMO

Copper (Cu) bioavailability varies under water conditions. In the present study, the whole life of zebrafish was divided into three different life stages (larvae, juvenile and adult) based on the growth curve, then the influences of water hardness and dissolved organic carbon (DOC) concentration on the acute toxicity of zebrafish were respectively investigated. The results indicated that the life stages had significant effects on Cu toxicity. The larvae stage was less sensitive to Cu than both the juvenile and adult stages. With the increase of water hardness, the toxicity of Cu on zebrafish was decreased, a linear relationship was observed between water hardness and Cu toxicity, and the same was true for DOC concentration. The results showed that taking the 24 days juvenile zebrafish to study the water quality criteria of Cu was stable, sensitive and economical.

11.
Life Sci ; 238: 116968, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31628914

RESUMO

AIMS: Colorectal cancer (CRC) is the third most common cancer worldwide. Nuclear factor erythroid 2-related factor 2 (Nrf2), a master regulator of many cytoprotective genes, plays a protective role in carcinogenesis. Recent studies have identified a specific gene-expression signature regulated by the Nrf2 pathway in lung adenocarcinoma and head-and-neck squamous cell cancer. However, the roles of Nrf2 in the development of colitis-associated colorectal cancer (CACC) have not been well characterized. Nrf2 target genes as prognostic biomarkers in CACC remain to be explored. Thus, this work aimed to identify the molecular changes that occur during mouse CACC progression to facilitate the development of diagnostic and prognostic biomarkers. MAIN METHODS: The CACC model was established using azoxymethane (AOM) with dextran sulfate sodium salt (DSS) in BALB/c mice for 3 weeks to induce colitis-associated adenoma (CAA, early stage) and for 9 weeks to induce colitis-associated carcinoma (CAC, late stage). Using RNA-sequencing and bioinformatics analyses we examined the mRNA expression profiles of 6 groups: wild-type control (WT-C), WT-CAA, WT-CAC, Nrf2 knockout control (Nrf2KO-C), Nrf2KO-CAA, and Nrf2KO-CAC. KEY FINDINGS: In the AOM/DSS model of colitis-associated tumorigenesis, Nrf2-/- mice showed a phenotype similar to WT mice, but with significantly more tumors and a much higher percentage of adenocarcinomas. We identified 47 novel Nrf2 genes via gene expression profiling of tumor samples. Survival analysis showed that 23 of these genes were biomarkers of a poor prognosis in colon cancer patients. SIGNIFICANCE: Nrf2 target genes deserve exploration as prognostic and therapeutic targets for CRC.

13.
Circ Res ; 125(9): 855-867, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31600125

RESUMO

Given that cardiovascular safety concerns remain the leading cause of drug attrition at the preclinical drug development stage, the National Center for Toxicological Research of the US Food and Drug Administration hosted a workshop to discuss current gaps and challenges in translating preclinical cardiovascular safety data to humans. This white paper summarizes the topics presented by speakers from academia, industry, and government intended to address the theme of improving cardiotoxicity assessment in drug development. The main conclusion is that to reduce cardiovascular safety liabilities of new therapeutic agents, there is an urgent need to integrate human-relevant platforms/approaches into drug development. Potential regulatory applications of human-derived cardiomyocytes and future directions in employing human-relevant platforms to fill the gaps and overcome barriers and challenges in preclinical cardiovascular safety assessment were discussed. This paper is intended to serve as an initial step in a public-private collaborative development program for human-relevant cardiotoxicity tools, particularly for cardiotoxicities characterized by contractile dysfunction or structural injury.

14.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3239-3245, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602878

RESUMO

The present study was conducted to explores the effects of short-term addition of 17ß-E2 on the growth,gonad development and internal quality of overwintering Whitmania pigra. Before overwintering,0. 0,1. 0,10. 0,25. 0,50. 0,100. 0 µg·L~(-1) of 17ß-E2 were added to the aquaculture water for 6 weeks and then hibernated for 60 days. The changes of growth performance,gonad index,morphological structure of spermary( ovary),endogenous steroid hormones level and internal quality were measured. The results showed that the body weight,weight gain rate,specific growth rate,female gonad index,oocyte development and endogenous estrogen level of the leech increased first and then decreased with the increase of the concentration of exogenous 17ß-E2,which were higher than those of the control group. The body weight,weight gain rate and specific growth rate of the leech at the concentration of 25 µg·L~(-1)17ß-E2 were significantly higher than those of the other groups( P<0. 05),oocyte development and endogenous estrogen levels were significantly higher than those of other groups at the concentration of 50 µg·L~(-1)( P<0. 05). When the concentration of exogenous 17ß-E2 was higher than 50 µg·L~(-1),the levels of male gonad index,spermatocyte development,endogenous androgen and progesterone were significantly inhibited( P< 0. 05). There was no significant difference in endogenous corticosteroid levels among the groups. In conclusion,short-term addition of exogenous 17ß-E2 of 10-25 µg·L~(-1) could promote the growth of overwintering leeches,oocyte development and antithrombin activity without inhibiting the development of male gonads.


Assuntos
Estradiol/farmacologia , Gônadas/crescimento & desenvolvimento , Sanguessugas/efeitos dos fármacos , Sanguessugas/crescimento & desenvolvimento , Androgênios/análise , Animais , Estrogênios/análise , Feminino , Gônadas/efeitos dos fármacos , Hibernação , Masculino , Progesterona/análise
15.
Curr Microbiol ; 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664502

RESUMO

Phage PA-YS35 is a novel lytic Pseudomonas aeruginosa phage belonging to the Myoviridae family and was isolated from the sewage of the First Hospital of Jilin University. The biological properties testing indicated that phage PA-YS35 is stable between - 20 and 60 °C and pH 4-9. The one-step growth curve shows that the latent period of PA-YS35 was 9 min, and the burst period was about 21 min by the size of approximately 380 progeny phages per host cell. The genome of phage PA-YS35 is linear double-stranded DNA with a size of 93,296 bp and a GC content of 49.35%. The results from RAST gene annotation analysis showed that the PA-YS35 genome contains 172 open reading frames (ORFs); the function of 41 ORFs can be predicted, whereas the product of remaining 131 ORFs are hypothetical proteins. According to phylogenetic tree of RNA ligase encoding sequence, phage PA-YS35 has a close evolutionary relationship with Pseudomonas phage PAK P1 because both of them are located on the same branch. The study of phage PA-YS35 genome will provide useful information for further research on the interaction between phages and their hosts.

16.
Top Stroke Rehabil ; : 1-6, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31566117

RESUMO

Objective: This meta-analysis systematically analyzed and compared oral health between stroke patients and controls. Data source: The electronic databases of PubMed, EMBASE, PsycINFO, Medline and Web of Science were independently searched by two authors from their inception to 14 June 2018. Study selection: Eleven studies comparing oral health between stroke patients (n = 1,742) and controls (n = 1,193) were analyzed. Data extraction: The full texts of the 11 studies were independently reviewed. Data on oral health were independently extracted by two authors. Data synthesis: Mean differences (MD) and 95% confidence intervals (CI) were calculated and synthesized using fixed or random-effects models, as appropriate. Compared to controls, stroke patients had poorer oral health: they had more Dental Caries (5 studies; MD = 2.89, 95% CI: 0.91-4.88, p= .04), but less Remaining Teeth scores (6 studies; MD = -2.93, 95% CI: -3.91, -1.95; p < .00001). Both the Plaque Index (3 studies; MD = 0.21, 95% CI: 0.14, 0.28; p < .00001) and Gingival Index scores (4 studies; MD = 0.22, 95% CI: 0.14, 0.30; p < .00001) were significantly higher in stroke patients, indicating worse periodontal status. Conclusions: Stroke patients had poorer overall oral health status compared to controls. Given the importance of oral health to overall health, further research on screening for oral health problems after stroke should be conducted and effective management strategies should be devised and implemented.

17.
J Neurosci ; 39(46): 9130-9144, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31604834

RESUMO

Neuropathic pain is one of the most common and notorious neurological diseases. The changes in cerebral structures after nerve injury and the corresponding contributions to neuropathic pain are not well understood. Here we found that the majority of glutamatergic neurons in the area 2 of midcingulate cortex (MCC Cg2Glu) were inhibited by painful stimulation in male mice. Optogenetic manipulation revealed that these neurons were tonically involved in the inhibitory modulation of multimodal nociception. We further identified the projections to GABAergic neurons in the zona incerta (ZIGABA) mediated the pain inhibitory role. However, MCC Cg2Glu became hypoactive after nerve injury. Although a brief activation of the MCC Cg2Glu to ZIGABA circuit was able to relieve the aversiveness associated with spontaneous ongoing pain, consecutive activation of the circuit was required to alleviate neuropathic allodynia. In contrast, glutamatergic neurons in the area 1 of MCC played opposite roles in pain modulation. They became hyperactive after nerve injury and only consecutive inhibition of their activity relieved allodynia. These results demonstrate that MCC Cg2Glu constitute a component of intrinsic pain inhibitory circuitry and their hypoactivity underlies neuropathic pain. We propose that selective and persistent activation of the MCC Cg2Glu to ZIGABA circuit may serve as a potential therapeutic strategy for this disease.SIGNIFICANCE STATEMENT Glutamatergic neurons in the area 2 of midcingulate cortex (MCC Cg2Glu) are tonically involved in the intrinsic pain inhibition via projecting to GABAergic neurons in the zona incerta. They are hypoactive after nerve injury. Selective activation of the circuit compensates the reduction of its analgesic strength and relieves neuropathic pain. Therefore, MCC Cg2Glu and the related analgesic circuit may serve as therapeutic targets for neuropathic pain. In contrast, MCC Cg1Glu have an opposite role in pain modulation and become hyperactive after nerve injury. The present study provides novel evidence for the concept that neuropathic pain is associated with the dysfunction of endogenous pain modulatory system and new perspective on the treatment of neuropathic pain.

18.
Artigo em Inglês | MEDLINE | ID: mdl-31535983

RESUMO

This paper studies Positive and Unlabeled learning (PU learning), of which the target is to build a binary classifier where only positive data and unlabeled data are available for classifier training. To deal with the absence of negative training data, we first regard all unlabeled data as negative examples with false negative labels, and then convert PU learning into the risk minimization problem in the presence of such one-side label noise. Specifically, we propose a novel PU learning algorithm dubbed "Loss Decomposition and Centroid Estimation" (LDCE). By decomposing the loss function of corrupted negative examples into two parts, we show that only the second part is affected by the noisy labels. Thereby, we may estimate the centroid of corrupted negative set via an unbiased way to reduce the adverse impact of such label noise. Furthermore, we propose the "Kernelized LDCE" (KLDCE) by introducing the kernel trick, and show that KLDCE can be easily solved by combining Alternative Convex Search (ACS) and Sequential Minimal Optimization (SMO). Theoretically, we derive the generalization error bound which suggests that the generalization risk of our model converges to the empirical risk with the order of O(1/ √k + 1 /√{n-k} + 1/ √n) ( n and k are the amounts of training data and positive data correspondingly). Experimentally, we conduct intensive experiments on synthetic dataset, UCI benchmark datasets and real-world datasets, and the results demonstrate that our approaches (LDCE and KLDCE) achieve the top-level performance when compared with both classic and state-of-the-art PU learning methods.

19.
Biochimie ; 167: 34-41, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31491441

RESUMO

ArgR, a transcriptional regulator belonging to the AraC/XylS family, plays a key role in arginine metabolism regulation. ArgR has also been found to repress the transcription of a lipase gene, but its molecular mechanism is still unknown. In this study, we investigated the molecular mechanism acting on the expression of intracellular lipase gene lipA regulated by ArgR in Pseudomonas protegens Pf-5 through knockout and overexpression of argR, detection of DNA-protein interaction in vivo, determining whole-cell lipase activities of various strains derived from Pf-5, and examining ß-galactosidase activities of various lacZ fusions. The results demonstrated that ArgR inhibits lipA expression at the transcriptional level. Further results showed that the inhibition of lipA transcription by ArgR is mediated by binding to the ArgR binding site of lipA promoter to produce steric hindrance, in which the common sequence, TGTCGC is crucial for the ArgR binding. Besides, arginine inhibits lipA expression in both wild-type and argR mutant, and shows a synergistic inhibition on lipA expression when combined with ArgR. To the best of our knowledge, this is the first report on ArgR directly repressing the transcription of a lipase gene.

20.
J Orthop Surg Res ; 14(1): 286, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31488167

RESUMO

BACKGROUND: Osteomyelitis is a challenge for orthopedic surgeons due to its protracted treatment process. Microwaves (MWs) can increase blood perfusion due to their thermal effect. Furthermore, MWs demonstrated significant bactericidal effects in vitro. In the present study, we assumed that the application of a 2450-MHz-frequency MW together with systemic antibiotic treatment would provide synergy for the treatment of acute osteomyelitis. METHODS: The medullary cavity of the right tibia was inoculated with 107 CFU of methicillin-sensitive Staphylococcus aureus (MSSA-ATCC 29213) in 40 rats, and the rats were randomly divided into four groups according to treatment: group I, saline (control); group II, saline + MW therapy; group III, systemic cefuroxime; and group IV, systemic cefuroxime + MW therapy. MWs were applied for 20 min per day to the infected limbs, and all rats were sacrificed on the 7th day. The severity of tibial osteomyelitis was assessed by quantitative culture analysis. RESULTS: Bacterial counts in groups III and IV were significantly reduced compared with those in the control (p = 0.001 and < 0.001, respectively). Furthermore, significant differences were detected between groups III and IV (p = 0.033). However, the difference between groups I and II was nonsignificant (p = 0.287). CONCLUSION: Our experimental model suggests that MW therapy provides a significant synergy for systemic antibiotic treatment. However, further clinical trials are required to safely use this treatment modality in patients.

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