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1.
ACS Appl Mater Interfaces ; 12(10): 11320-11328, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32067461

RESUMO

Nanomaterials with intrinsic peroxidase-like activities are able to catalyze the oxidation of the substrate with the peroxide, which have been widely considered as artificial enzymatic agents in cancer therapy. However, current peroxidase catalytic oxidation treatments generating reactive oxygen species rely highly on hydrogen peroxide and pH, which limit greatly their therapeutic efficiency in the tumor microenvironment. Here, we report a strategy to construct the complex virus-like Fe3O4@Bi2S3 nanocatalysts (F-BS NCs) by connecting typical peroxidase Fe3O4 (MNPs) with a narrow band gap semiconductor Bi2S3 (BS) to enhance the enzymatic activity resorting to the limited intratumoral peroxide and efficient external photothermal stimuli. In this formulation, the integrated F-BS NCs induce cancer-cell death through mild photothermal treatment and sequential photothermal-stimulative catalysis of H2O2 into highly toxic •OH under 808 nm laser, which successfully realize a remarkable synergistic anticancer achievement.

2.
BMC Microbiol ; 20(1): 36, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070273

RESUMO

BACKGROUND: Klebsiella pneumoniae is considered the most clinically relevant species of Enterobacteriaceae, known to cause severe infections including liver abscesses. To the best of our knowledge, a large proportion of iron in the human body is accumulated and stored in the liver. We hypothesize that increased iron availability is an important factor driving liver abscess formation and we therefore aim to understand the effects of iron on K. pneumoniae causing liver abscesses. RESULTS: All tested K. pneumoniae clinical isolates, including those isolated from liver abscesses and other abdominal invasive infection sites, grew optimally when cultured in LB broth supplemented with 50 µM iron and exhibited the strongest biofilm formation ability under those conditions. Decreased growth and biofilm formation ability were observed in all tested strains when cultured with an iron chelator (P < 0.05). The infection model of G. mellonella larvae indicated the virulence of liver abscess-causing K. pneumoniae (2/3) cultured in LB broth with additional iron was significantly higher than those under iron-restricted conditions (P < 0.05). The relative expression levels of the four siderophore genes (iucB, iroB, irp1, entB) in K. pneumoniae strains isolated from liver abscesses cultured with additional iron were lower than those under iron-restricted conditions (P < 0.05). CONCLUSIONS: It is suggested by our research that iron in the environment can promote growth, biofilm formation and enhance virulence of K. pneumoniae causing liver abscesses. A lower expression of siderophore genes correlates with increased virulence of liver abscess-causing K. pneumoniae. Further deeper evaluation of these phenomena is warranted.

3.
J Clin Nurs ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32017241

RESUMO

AIMS AND OBJECTIVES: To evaluate the effectiveness of horticultural therapy on cognitive function, agitation, positive emotion and engagement in people with dementia. BACKGROUND: The number of people with dementia is increasing rapidly, and nonpharmacological interventions such as horticultural therapy have been recommended as the first choice for these patients. Horticultural therapy involves participatory and ornamental horticultural therapy. Many original studies have examined the effectiveness of horticultural therapy in the last two decades. However, these studies vary in types of interventions, outcomes and measurement. DESIGN: A quantitative systematic review and meta-analysis. METHODS: This systematic review was conducted under PRISMA guidelines. Randomised controlled trials (RCTs) and quasi-experimental studies involving horticultural therapy for people with dementia were included. Risk of bias was assessed by the Cochrane's and Joanna Briggs Institute's tool. Reference lists and a relevant journal were searched. Meta-analyses were conducted using RevMan 5.3. PubMed, CINAHL, Embase, BIOSIS Previews, Web of Science Core Collection, China National Knowledge Infrastructure, Wanfang, SinoMed, Cochrane Library and ProQuest Health & Medical Complete were searched. Studies from database inception to 1 July 2019 were included. RESULTS: This systematic review included 14 studies (4 RCTs and 10 quasi-experimental studies) involving 411 people with dementia. The results of meta-analyses indicated that significant differences were found in the effectiveness of participatory horticultural therapy on total score of cognitive function, agitation, positive emotion and engagement, but not in the effectiveness of ornamental horticultural activities on agitation and positive emotion. CONCLUSIONS: The existing evidence supports the effectiveness of participatory horticultural therapy on cognitive function, agitation, positive emotion and engagement. Future high-quality original studies are needed to draw more robust conclusions. RELEVANCE TO CLINICAL PRACTICE: The results support the use of participatory horticultural therapy for improving cognitive function, agitation, positive emotion and engagement of people with dementia.

4.
Hum Gene Ther ; 31(5-6): 367-375, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31950871

RESUMO

Renal fibrosis leads to end-stage renal disease, but antifibrotic drugs are difficult to develop. Chronic kidney disease often results in muscle wasting, and thereby increases morbidity and mortality. In this work, adeno-associated virus (AAV)-mediated overexpressing miR-29a was hypothesized to counteract renal fibrosis and muscle wasting through muscle-kidney crosstalk in unilateral ureteral obstruction (UUO) mice. miR-29a level was downregulated in the kidney and skeletal muscle of UUO mice. The secretion of exosome-encapsulated miR-29a increased in cultured skeletal muscle satellite cells and HEK293 renal cells after stimulation with serum from UUO mice. This result was confirmed by qPCR and microRNA deep sequencing in the serum exosomes of mice with obstructed ureters. A recombinant AAV-miR-29a was generated to overexpress miR-29a and injected into the tibialis anterior muscle of the mice 2 weeks before UUO surgery. AAV-miR-29a abrogated the UUO-induced upregulation of YY1 and myostatin in skeletal muscles. Renal fibrosis was also partially improved in the UUO mice with intramuscular AAV-miR-29a transduction. AAV-miR-29a overexpression reversed the increase in transforming growth factor ß, fibronectin, alpha-smooth muscle actin, and collagen 1A1 and 4A1 levels in the kidney of UUO mice. AAV-green fluorescent protein was applied to trace the AAV route in vivo, and fluorescence was significantly visible in the injected/uninjected muscles and in the kidneys. In conclusion, intramuscular AAV-miR-29a injection attenuates muscle wasting and ameliorates renal fibrosis by downregulating several fibrotic-related proteins in UUO mice.

5.
BMC Microbiol ; 20(1): 7, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31914918

RESUMO

BACKGROUND: Colistin resistance is considered a serious problem due to a lack of alternative antibiotics. The Rapid ResaPolymyxin Acinetobacter/Pseudomonas NP test is a resazurin reduction-based technique that relies on the visual detection of bacterial growth in the presence of a defined concentration of colistin. The aim of this study was to evaluate the performance of the Rapid ResaPolymyxin Acinetobacter/Pseudomonas NP test in the detection of colistin susceptibility in common clinical Gram-negative bacteria. RESULTS: A total of 253 clinical isolates from a teaching hospital, including Acinetobacter baumanii (n = 58, 8 colistin-resistant), Pseudomonas aeruginosa (n = 61, 11 colistin-resistant), Klebsiella pneumoniae (n = 70, 20 colistin-resistant) and Escherichia coli (n = 64, 14 colistin-resistant) were tested in this study. The sensitivity and specificity of the Rapid ResaPolymyxin Acinetobacter/Pseudomonas NP test compared to Broth microdilution method was 100 and 99%, respectively. CONCLUSIONS: Our results suggest that Rapid ResaPolymyxin Acinetobacter/Pseudomonas NP test could be used as an accurate detection method for colistin resistance.

6.
Nanoscale ; 12(6): 3846-3854, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-31995084

RESUMO

High treatment efficiency and low drug toxicity are two key factors in tumor therapy. The development of multifunctional drug carrier systems is of great significance for the diagnosis and therapy of tumors. Herein, a novel biodegradable treatment system based on zeolitic imidazolate framework-90 (ZIF-90) was designed in this study. This 5-FU@ZIF-90@ZnO (FZZ) drug delivery system achieves synergistic treatment with antineoplastic 5-fluorouracil (5-FU) and zinc oxide, and also has good dispersibility in the acidic tumor microenvironment (TME), which enables the drug to achieve pH-controlled delivery in acidic organisms. Interestingly, zinc oxide nanoparticles can play a dual role here. They can prevent the premature leakage of drugs under physiological conditions. Moreover, Zn2+ produced after the decomposition of nanoparticles can act as a therapeutic agent, overcoming the tumor resistance to 5-FU and regulating a series of physiological reactions to inhibit tumor growth. It is worth noting that the porous ZIF-90 is an emerging drug carrier with a relatively high drug loading rate of 39% in this study. Synergistic 5-FU and ZnO nanoparticles have achieved tumor inhibition and have shown high therapeutic biosafety. Thus, the FZZ core-shell nanoparticles are a potential pH-controlled drug release system that can be applied to tumor treatment.

7.
Food Chem ; 311: 126055, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31862564

RESUMO

Imidacloprid is a highly effective insecticide, but its potential hazards to the environment and ecosystems have limited its use in many regions. A fast and sensitive analytical method would aid monitoring imidacloprid residues. The monoclonal antibody 4D9, colloidal gold and time-resolved fluorescent nanobeads (CGN and TRFN, respectively) were applied to develop a lateral flow immunoassay (LFIA) for imidacloprid detection in the present work. Both the optimized TRFN-LFIA and CGN-LFIA had a similar limit of detection of approximately 0.02 ng/mL. Use of the portable optical scanner with the TRFN-LFIA or CGN-LFIA could quantitate concentrations of imidacloprid in vegetable as sensitively as the enzyme-linked immunosorbent assay (ELISA). The LFIAs quantitative results of imidacloprid in commercial Chinese leeks were verified by the liquid chromatography-mass spectrometry with a R2 of 0.91. The LFIAs are portable and simple and thus could fully replace the ELISA for onsite quantitation of imidacloprid residues in vegetables.

8.
Int J Nurs Stud ; 102: 103489, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31862527

RESUMO

BACKGROUND: Agitation in people with dementia is common and distressing and can lead to increased caregiver burden. However, medications often have adverse reactions and limited effectiveness. Thus, non-pharmacological interventions are being increasingly implemented. OBJECTIVES: To compare and rank the efficacy of different non-pharmacological interventions in the management of agitation in people with dementia. DESIGN: Bayesian network meta-analysis. METHODS: A comprehensive electronic literature search was performed in five English databases and three Chinese databases to identify relevant randomized controlled trials (RCTs) that were published up to January 2019. A random-effects model was selected to conduct traditional meta-analysis to directly examine the efficacy of different non-pharmacological interventions. The consistency model was selected to conduct a network meta-analysis to evaluate the relative effects and rank probability of different non-pharmacological interventions. RESULTS: A total of 65 RCTs were included in this network meta-analysis involving 11 different non-pharmacological interventions. Network meta-analysis showed that massage therapy, animal-assisted intervention, and personally tailored intervention were associated with more substantial reductions in agitation compared with other interventions and controls. CONCLUSIONS: Our study confirmed the effectiveness of non-pharmacological interventions for ameliorating agitation in people with dementia and recommended several interventions for clinical practice. Healthcare professionals should be encouraged to apply promising non-pharmacological interventions (e.g. massage therapy, animal-assisted intervention and personally tailored intervention) for people with dementia during routine care.

9.
ACS Appl Mater Interfaces ; 11(51): 47730-47738, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31790193

RESUMO

To date, the limited light conversion ability and the oxygen-dependent therapeutic process of most photosensitizers make it difficult to achieve satisfactory therapeutic effects in the complex tumor microenvironment, especially the anoxic environment. Herein, the black mesoporous titania (BMT) with large pore size (∼8 nm) is synthesized as a new-style carrier for radical generator drug (AIBI) loading. The BMT as a light transducer can convert near-infrared (NIR) light energy into thermal energy and chemical energy (•OH), contributing to photothermal therapy (PTT) and photodynamic therapy (PDT), respectively. More importantly, AIBI would be thermally decomposed into alkyl radicals (•R) for thermodynamic therapy (TDT). The high concentration of free radicals produced by BMT@AIBI NCs resulted in double-strand breaks (DSBs) of DNA and finally induced cancer cell apoptosis. Since the generation of radicals is unrelated to oxygen, the BMT@AIBI NCs with NIR irradiation presented excellent in vitro and in vivo anticancer results under hypoxic conditions. The reported NIR-induced platform based on BMT@AIBI NCs, which could perform triple energy-conversion processes including light energy to thermal energy, to chemical energy, and to thermal energy then to chemical energy, realizes synergetic photo-thermal-dynamic therapy (PTT, PDT, and TDT) to overcome the problem of tumor hypoxia for enhanced anticancer effects.

10.
Medicine (Baltimore) ; 98(48): e17093, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31770192

RESUMO

BACKGROUND: Although Billroth II and Roux-en-Y procedures are the two most commonly performed types of reconstruction techniques following distal stomach resection, there is yet no consensus on which reconstruction is the best choice. This meta-analysis aims to compare the perioperative safety and long-term complications of Billroth-II and Roux-en-Y reconstruction. METHOD: We searched the databases of the PubMed, the Cochrane Library, Web of Science, EMBASE, and the Chinese Biomedicine Database from January 2000 to January 2018 and included studies that compared Roux-en-Y with Billroth-II reconstruction after distal gastrectomy for gastric cancer. The meta-analyses were performed using RevMan 5.0 software. RESULT: Four randomized controlled trials (RCTs) and eight non-randomized observational clinical studies (OCS) were included. Billroth-II anastomosis was more beneficial than Roux-en-Y in reducing the operation time (OR = 34.14, 95%CI = 24.19-44.08, P < .00001, I = 54%) and intraoperative blood loss (OR = 54.32, 95%CI = 50.29-58.36, P < .00001, I = 36%). However, Roux-en-Y anastomosis was more beneficial than Billroth-II in reducing the incidence of remnant gastritis (OR = 0.12; 95% CI = 0.08-0.17; P < .00001; I = 8%), reflux esophagitis (OR = 0.26; 95%CI = 0.15-0.44; P < .00001; I = 0%), dumping symptoms (OR = 0.31; 95%CI = 0.13-0.73; P = .008; I = 0%), reflux symptoms (OR = 0.20; 95% CI = 0.10-0.42; P < .0001; I = 0%). No differences were found between the two groups with respect to anastomotic leakage (OR = 1.56, 95%CI = 0.66-3.64, P = .59, I = 0%); postoperative mortality (OR = 1.15, 95%CI = 0.38-3.51, P = .80, I = 0%); overall postoperative morbidity (OR = 0.92, 95%CI = 0.6-1.42, P = .72, I = 0%); and delayed gastric emptying (OR = 0.84, 95%CI = 0.40-1.77, P = .65, I = 0%). CONCLUSION: Roux-en-Y reconstruction does not carry greater postoperative complications than the Billroth II reconstruction. Additionally, it can improve the postoperative quality of life owing to less remnant gastritis, reflux esophagitis, dumping symptoms, and reflux symptoms. Considering the long-term postoperative outcomes, Roux-en-Y reconstruction appears to be a better choice following distal stomach resection.


Assuntos
Anastomose em-Y de Roux/efeitos adversos , Gastrectomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Procedimentos Cirúrgicos Reconstrutivos/efeitos adversos , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Anastomose em-Y de Roux/métodos , Perda Sanguínea Cirúrgica , Esofagite Péptica/etiologia , Feminino , Gastrectomia/métodos , Gastrite/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Preferência do Paciente , Período Pós-Operatório , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Procedimentos Cirúrgicos Reconstrutivos/métodos
11.
Worldviews Evid Based Nurs ; 16(6): 478-484, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31638313

RESUMO

BACKGROUND: Calcium homeostasis and bone health are an increasing concern for middle-aged and older adults. Many studies have explored the positive effects of probiotics, prebiotics, or synbiotics on serum calcium and bone mineral density (BMD) or other parameters related to bone health. However, the participants, the species, doses and duration of interventions, outcomes, and measurements varied among these studies. AIMS: To systematically evaluate the effect of probiotics, prebiotics, or synbiotics on maintaining calcium homeostasis and improving bone health in middle-aged and older adults. METHODS: We identified studies in Cochrane Library, Embase, PubMed, Web of Science, CINAHL, China National Knowledge Infrastructure, and Wanfang and articles in English and Chinese published from inception up to January 10, 2019. Randomized controlled trials (RCTs) involving probiotics, prebiotics, or synbiotics for middle-aged or older adults were employed for meta-analysis by using RevMan 5.3, and heterogeneity and risk of bias assessment were performed. RESULTS: A total of eight studies, involving 564 participants, were included. Probiotics, prebiotics, or synbiotics supplementation was able to significantly elevate serum calcium levels (0.52 mg/dl, 95% CI [0.38, 0.66]), heterogeneity: p = .13, I2  = 44%), while the results of meta-analysis failed to support the effects of this supplementation on the parameters related to bone health in middle-aged and older adults, including BMD, parathyroid hormone, osteocalcin, and alkaline phosphatase. LINKING EVIDENCE TO ACTION: Probiotics, prebiotics, or synbiotics supplementation exerts a facilitating influence on the level of serum calcium, while the present study has not yet supported the beneficial effects of such interventions on bone health. Therefore, further studies with high-quality RCTs are required to determine the effects of probiotics, prebiotics, or synbiotics supplementation on middle-aged and older adults.

12.
J Food Sci ; 84(11): 3296-3302, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31589343

RESUMO

Carbofuran residue in vegetables is a concern to human health. Direct competitive enzyme-linked immunosorbent assay (dcELISA) and dipstick immunoassay were developed in the present study. The dcELISA showed a 50% inhibition concentration (IC50 ) and working range of 1.3 and 0.2 to 7.5 ng/mL, respectively, while the cutoff value of dipstick immunoassay was 20 ng/mL. Applying the two immunoassays, we achieved the goal of rapid screening of carbofuran residue in commercial vegetables with a simple sample processing method. Among 46 leek, 39 potato, and 39 sweet potato samples, carbofuran residue was detected in 22% of the leek samples, and two samples exceeded the maximum residue limit of China (0.02 mg/kg). In addition, carbofuran residue was found at less than 2.5 ng/g in one potato and one sweet potato samples. The residual level of carbofuran measured by immunoassays agreed well with those determined by ultra-performance liquid chromatography tandem mass spectrometry. To ensure food safety and human health, it is greatly necessary and meaningful to monitor carbofuran residue in commercial vegetables. PRACTICAL APPLICATION: Rapid monitoring of carbofuran residue in vegetables is very necessary and important for consumers, regulatory agencies, and food industry.


Assuntos
Carbofurano/análise , Resíduos de Drogas/análise , Imunoensaio/métodos , Inseticidas/análise , Verduras/química , China , Cromatografia Líquida , Ensaio de Imunoadsorção Enzimática/métodos , Contaminação de Alimentos/análise , Humanos
13.
Cancer Med ; 8(18): 7532-7541, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31642189

RESUMO

We assessed the clinical utility of contrast-enhanced ultrasonography (CEUS) in the diagnosis of benign and malignant small renal masses using a meta-analysis of diagnostic test. We performed a comprehensive online search in the following database including PubMed, Embase, Web of Science, Wanfang, and Chinese National Knowledge Infrastructure from the inception to August 25, 2019. the following index were calculated for assessing the diagnostic ability, including sensitivity, specificity, diagnostic odds ratio (DOR), negative likelihood ratio (NLR), positive likelihood ratio (PLR), area under the curve (AUC) with 95% confidence intervals (CIs). Seventeen studies were included in the qualitative and quantitative analyses. The overall sensitivity was 0.93 with 95% CI of 0.88-0.95. The specificity was 0.71 and the 95% CI was 0.60-0.80. The pooled AUC was 0.91 (95% CI: 0.88-0.93). The diagnostic odds ratio was 31 (95% CI: 21-45). The NLR and PLR were 0.10 (95% CI: 0.07-0.15) and 3.2(95% CI: 2.3-4.4), respectively. There is a slight heterogeneity within studies. The subgroup analysis was also performed. For retrospective and perspective, the sensitivity and specificity were 0.93, 0.92 and 0.71, 0.73; For different diameter lesions, the sensitivity and specificity were 0.93, 0.94 and 0.64, 0.74; For sample size (≤median vs. >median), the sensitivity and specificity were 0.94, 0.93 and 0.67, 0.77. The Deek's funnel plot asymmetry test in indicated no publication bias. The CEUS have a high diagnostic ability in differentiating benign and malignant small renal masses among Asian population.

14.
Front Public Health ; 7: 229, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31552210

RESUMO

Carbapenem-resistant, hypervirulent Klebsiella pneumoniae (CR-hvKP) has recently emerged as a significant threat to public health. In this study, 29 K. pneumoniae isolates were isolated from eight patients admitted to the intensive care unit (ICU) of a comprehensive teaching hospital located in China from March 2017 to January 2018. Clinical information of patients was the basis for the further analyses of the isolates including antimicrobial susceptibility tests, identification of antibiotic resistance and virulence gene determinants, multilocus sequence typing (MLST), XbaI-macrorestriction by pulsed-field gel electrophoresis (PFGE). Selected isolates representing distinct resistance profiles and virulence phenotypes were screened for hypervirulence in a Galleria mellonella larvae infection model. In the course of the outbreak, the overall mortality rate of patients was 100% (n = 8) attributed to complications arising from CR-hvKP infections. All isolates except one (28/29, 96.6%) were resistant to multiple antimicrobial agents, and harbored diverse resistance determinants that included the globally prevalent carbapenemase bla KPC-2. Most isolates had hypervirulent genotypes being positive for 19 virulence-associated genes, including iutA (25/29, 86.2%), rmpA (27/29, 93.1%), ybtA (27/29, 93.1%), entB (29/29, 100%), fimH (29/29, 100%), and mrkD (29/29, 100%). MLST revealed ST11 for the majority of isolates (26/29, 89,7%). Infection assays demonstrated high mortality in the Galleria mellonella model with the highest LD50 values for three isolates (<105 CFU/mL) demonstrating the degree of hypervirulence of these CR-hvKP isolates, and is discussed relative to previous outbreaks of CR-hvKP.

15.
Int J Mol Med ; 44(5): 1781-1788, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31545399

RESUMO

The reduction of podocyte injury is a key strategy in controlling proteinuria, which is the main early clinical manifestation of diabetic nephropathy (DN). Impaired autophagic flux is the primary mechanism responsible for podocyte injury in DN. The aim of the present study was to elucidate the effect of connexin 43 (Cx43) on impaired autophagic flux in podocyte injury and to explore its molecular mechanism of action in DN. Sprague­Dawley rats were administered streptozocin (STZ) to construct a DN animal model. Podocytes were incubated in media containing either buffer or high glucose (HG; 30 mM) for variable time periods. The podocytes were then examined and the mechanism of injury was investigated using an Annexin V/PI assay, immunofluorescence staining, western blotting, and RNA interference. In vivo, STZ­induced DN rats with or without Cx43 knockdown were established to observe the role of Cx43 in autophagic flux and podocyte injury. We observed that HG induced podocyte injury, accompanied by increases in Cx43 expression and impaired autophagic flux, as evidenced by the accumulation of LC3II/LC3I and p62. Interestingly, the silencing of Cx43 expression ameliorated autophagic flux impairment and reduced podocyte injury via suppression of the mammalian target of rapamycin pathway. Furthermore, impaired autophagic flux also blocked the degradation of Cx43. In vitro studies indicated that higher numbers of Annexin V/PI­positive podocytes, impaired autophagic flux and increased Cx43 expression were observed in HG­induced podocyte injury relative to the control group. The pathogenic effect of Cx43 on impaired autophagic flux and podocyte injury was also confirmed by Cx43 knockdown. The present study provided preliminary evidence indicating that the interdependence of Cx43 and impaired autophagic flux represents a novel mechanism of podocyte injury in DN. Hence, the Cx43­autophagy loop is a potentially relevant therapeutic target for the treatment of DN.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31383654

RESUMO

The goal was to investigate the mechanisms of colistin resistance and heteroresistance in Pseudomonas aeruginosa clinical isolates. Colistin resistance was determined by the broth microdilution method. Colistin heteroresistance was evaluated by population analysis profiling. Time-kill assays were also conducted. PCR sequencing was performed to detect the resistance genes among (hetero)resistant isolates, and quantitative real-time PCR assays were performed to determine their expression levels. Pulsed-field gel electrophoresis and multilocus sequence typing were performed. Lipid A characteristics were determined via matrix-assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF MS). Two resistant isolates and 9 heteroresistant isolates were selected in this study. Substitutions in PmrB were detected in 2 resistant isolates. Among heteroresistant isolates, 8 of 9 heteroresistant isolates had nonsynonymous PmrB substitutions, and 2 isolates, including 1 with a PmrB substitution, had PhoQ alterations. Correspondingly, the expression levels of pmrA or phoP were upregulated in PmrB- or PhoQ-substituted isolates. One isolate also found alterations in ParRS and CprRS. The transcript levels of the pmrH gene were observed to increase across all investigated isolates. MALDI-TOF MS showed additional 4-amino-4-deoxy-l-arabinose (l-Ara4N) moieties in lipid A profiles in (hetero)resistant isolates. In conclusion, both colistin resistance and heteroresistance in P. aeruginosa in this study mainly involved alterations of the PmrAB regulatory system. There were strong associations between mutations in specific genetic loci for lipid A synthesis and regulation of modifications to lipid A. The transition of colistin heteroresistance to resistance should be addressed in future clinical surveillance.

17.
Molecules ; 24(16)2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31412567

RESUMO

Taxus cuspidata S. et Z. is an excellent natural source of bioactive polysaccharides and has various biological activities. The objective of this study was to evaluate the effect of antidiabetic and antitumor activities of polysaccharides from Taxus cuspidata branches and leaves (TCBL) and to determine the optimum extraction technology of TCBL using a low-temperature and high-efficiency enzyme and ultrasound-assisted coupled extraction (EUCE) method. Optimal technology parameters were determined as follows: an extraction temperature of 51 °C, an extraction time of 33 min, a ratio of material to liquid of 1:19 (g:mL), and an enzyme concentration of 0.10 mg·mL-1. Under the optimized conditions, the polysaccharide yield from TCBL obtained by EUCE was 4.78% ± 0.18%. The four purified polysaccharides (Pe1, Pe2, Pe3, Pe4) from TCBL are mainly composed of arabinose, galactose, glucose, a small amount of xylose, and mannose. This composition was assessed by HPIC analysis. The antidiabetic activity and antitumor activity of polysaccharides from TCBL were assayed in vitro. Among the four purified polysaccharides from TCBL, purified Pe4 had the highest inhibitory capacity against α-glucosidase, and its IC50 value was 123.0 µg·mL-1. Pe1 had the highest antitumor capacity against MCF7 cells and HepG2 cells, with IC50 values of 169.0 and 132.0 µg·mL-1. Pe4 had the highest antitumor effect on human cervical cancer cells (Hela), and its IC50 value was 89.9 µg·mL-1. Pe4 polysaccharide demonstrated a good α-glucosidase inhibitory activity and antitumor capacity against Hela cells. Therefore, Pe4 polysaccharide from TCBL is a beneficial source of potential inhibitors of type II diabetes and human cervical cancer activity.


Assuntos
Fracionamento Químico , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Taxus/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Fracionamento Químico/métodos , Relação Dose-Resposta a Droga , Humanos , Monossacarídeos/química , Extratos Vegetais/química , Folhas de Planta/química , Polissacarídeos/química , Análise Espectral , Ondas Ultrassônicas
18.
Acta Biomater ; 99: 295-306, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31437636

RESUMO

Although neodymium vanadate (NdVO4) has been investigated and applied in some fields owing to its intensive ultraviolet (UV) light absorption, weak absorption in visible (Vis) and near infrared (NIR) regions constrains its environmental remediation and biomedical applications. Herein, plasmonic precious metal Au as light trapping agent is deposited onto NdVO4 to form metal/semiconductor hybrid nanostructure for improving the Vis/NIR light absorption. NdVO4/Au heterojunction nanocrystals (NCs) were synthesized by NdVO4 nanorods (NRs) and plasmonic Au nanoparticles (NPs), followed by introducing polyvinylpyrrolidone (PVP) to enhance stability and biocompatibility, which exhibit elevated photocatalytic performance for organic dye degradation, photothermal conversion effect as high as 32.15% and cytotoxic reactive oxygen species (ROS) production ability. NdVO4/Au can be internalized efficiently via endocytosis and cause apparent phototoxicity on HeLa cells. In vivo experiments further show that NdVO4/Au can act as a high-efficiency NIR light-triggered anticancer agent with excellent tumor inhibition effect. In addition, based on outstanding light-to-heat conversion performance and thermal expansion effect under NIR irradiation, NdVO4/Au provides photothermal (PT) and photoacoustic (PA) dual-modal imaging platform for precise cancer diagnosis and treatment. STATEMENTS OF SIGNIFICANCE: It's the first report on integrating precious metal Au and rare earth orthovanadates semiconductor into NdVO4/Au heterojunction NCs. The as-prepared NdVO4/Au heterojunction NCs exhibits improved absorption in Vis/NIR region and increased generation efficiency of photo-induced electron/hole pairs due to the LSPR effect, which results in enhanced photothermal conversion efficiency and the production ability of cytotoxic O2- and OH in comparison with pristine NdVO4. For further clinical application, NdVO4/Au heterojunction NCs could be served as anticancer therapeutic agent for PA/PT dual-modal imaging guided and NIR-triggered photothermal/photodynamic synergistic anticancer treatment.

19.
J Oncol ; 2019: 9784039, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31312217

RESUMO

Background: The prognostic relevance of gastric tumor location has been reported and debated. Our study was conducted to examine the differences in clinicopathological features, prognostic factors, and overall survival (OS) between patients with proximal gastric cancer (PGC) and distal gastric cancer (DGC). Patients and Methods: Patients with PGC or DGC were identified from the China National Cancer Center Gastric Cancer Database (NCCGCDB) during 1997-2017. Survival analysis was performed via Kaplan-Meier estimates and Cox proportional hazards models. Results: We reviewed 16,119 cases of gastric cancer patients, including 6,479 of PGC and 9,640 of DGC. PGC patients presented as older patients (61.5 versus 56.4 years, P<0.001) and more males (82.9% versus 68.2%, P<0.001). Compared with DGC, PGC was more likely to be in later pT stage (pT3 and pT4, 65.0% versus 52.8%, P<0.001) and lymph node metastasis (54.8% versus 50.9%, P<0.001). In univariate analysis, PGC patients had a worse survival outcome in stage I (Hazard ratio [HR] = 2.04, 95% CI: 1.42-2.94) but a better prognosis in stage IV (HR = 0.85, 95% CI: 0.73-0.98) when compared to DGC patients. However, multivariate analysis demonstrated that PGC was not an independent predictor for poor survival (HR = 1.07, 95% CI: 1.00-1.14). Results from multivariate analysis also revealed that pT4, lymph node metastasis, distant metastasis, no gastrectomy, and Borrmann IV were independent predictors associated with poor survival for both PGC and DGC patients. Additional prognostic factors for PGC patients included underweight (BMI < 18.5) (HR = 1.29, 95% CI: 1.06-1.58), linitis plastica (HR = 2.13, 95% CI: 1.25-3.65), and overweight (23 ≤ BMI <27.5) (HR = 0.80, 95% CI: 0.71-0.90). During the 20-year study period, the 5-year OS increased significantly for both PGC and DGC, with the increase rate of 91.7% and 67.7%, respectively. Conclusion: In China, PGC significantly differed from DGC in clinicopathological characteristics and prognostic factors. However, there was no significant relationship between survival outcome and gastric tumor location.

20.
Sci Total Environ ; 686: 118-130, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31176811

RESUMO

Marine submerged aquatic angiosperms (seagrasses) are declining globally. The species Zostera japonica Asch. & Graebn. is endangered in its native range in Asia, but has been successfully introduced to North America. A large area (1031.8 ha) of Z. japonica meadow has recently been discovered in the intertidal zone of Yellow River Delta, China. This seagrass occurs along both sides of the river mouth, forming dense meadows in turbid water conditions. Seasonal investigations over two years were conducted to examine the distribution, biomass, seed reproduction, seed bank, and population recruitment of the seagrass meadows at three sites in the intertidal zone. The meadows generally showed relatively high coverage, biomass, reproductive effort, and seed production in August. The seed bank was found to be large and contributed to population recruitment. There were significant inter-annual variations overall, and at individual sites. These variations are likely due to winter temperatures, which determine the abundance of overwintering shoots and seedling success. Differences in micro-topography may also play a role in producing variations in seedling success between sites. Microsatellite analysis revealed a high genetic exchange between the two sides of the river mouth. The results indicate that the seagrass bed in the Yellow River Delta shallow waters is in good condition, which can be attributed to its location within a national nature reserve. Establishment of protected areas might act as an effective way to mitigate the anthropogenic disturbance, conserve the seagrass meadows, and then enhance critical ecosystem functions.


Assuntos
Ecossistema , Zosteraceae/crescimento & desenvolvimento , Biomassa , China , Pradaria , Rios
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