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1.
Biochim Biophys Acta Gen Subj ; 1864(1): 129455, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31669585

RESUMO

BACKGROUND: Borrelia burgdorferi causes Lyme disease, the most common tick-borne illness in the United States. The Center for Disease Control and Prevention estimates that the occurrence of Lyme disease in the U.S. has now reached approximately 300,000 cases annually. Early stage Borrelia burgdorferi infections are generally treatable with oral antibiotics, but late stage disease is more difficult to treat and more likely to lead to post-treatment Lyme disease syndrome. METHODS: Here we examine three unique 5'-methylthioadenosine/S-adenosylhomocysteine (MTA/SAH) nucleosidases (MTNs or MTANs, EC 3.2.2.9) responsible for salvage of adenine and methionine in B. burgdorferi and explore their potential as antibiotic targets to treat Lyme disease. Recombinant Borrelia MTNs were expressed and purified from E. coli. The enzymes were extensively characterized for activity, specificity, and inhibition using a UV spectrophotometric assay. In vitro antibiotic activities of MTN inhibitors were assessed using a bioluminescent BacTiter-Glo™ assay. RESULTS: The three Borrelia MTNs showed unique activities against the native substrates MTA, SAH, and 5'-deoxyadenosine. Analysis of substrate analogs revealed that specific activity rapidly dropped as the length of the 5'-alkylthio substitution increased. Non-hydrolysable nucleoside transition state analogs demonstrated sub-nanomolar enzyme inhibition constants. Lastly, two late stage transition state analogs exerted in vitro IC50 values of 0.3-0.4 µg/mL against cultured B. burgdorferi cells. CONCLUSION: B. burgdorferi is unusual in that it expresses three distinct MTNs (cytoplasmic, membrane bound, and secreted) that are effectively inactivated by nucleoside analogs. GENERAL SIGNIFICANCE: The Borrelia MTNs appear to be promising targets for developing new antibiotics to treat Lyme disease.

2.
Ann Anat ; 227: 151421, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31563572

RESUMO

PURPOSE: Our group had recently described human hand Pacinian corpuscles (PCs): the hand PCs are not simply arranged along the digital palmar nerves but often exhibited specific morphologies known uncommonly. However, there is still no or few information about human foot PCs. MATERIALS AND METHODS: We observed transverse sections of all five toes including the interdigital area obtained from 12 feet of eight fetuses at 28-33 weeks (crown-rump length 230-290mm). Serial sections were prepared for 3D reconstructions and measurement. RESULTS: Foot PCs were characterized by (1) a dense distribution in the interdigital area in contrast to a few PCs in the distal tip of the all five toes; (2) abundant dorsal PCs including those in the nail bed and: (3) a long chain of PCs in the flexor tendon sheath of all five toes. Therefore, a distal dominance was not evident in the foot in contrast to the hand and, a tendon sheath contained much greater numbers of PCs than the hand. A tree-like or bouquet-like arrangement of PCs along a short perforating artery to the palmar digital skin was seen in the foot as we had described in the hand. The tree of foot PCs was sometimes seen laying transversely along the digital skin surface, not toward the skin. CONCLUSION: It is still unknown that, in utero, how the PCs distribution became different between the hand and foot: it might be determined genetically in a region-specific manner.

3.
J Nanosci Nanotechnol ; 20(4): 2598-2602, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492282

RESUMO

AlN nanowires macro-array were successfully fabricated on Si substrate by double template method and chemical vapour deposition. The research shows that AlN nanowires array with different diameter, length and coverage can be prepared by controlling the experimental conditions. The as-prepared AlN nanowires array were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, the Ultraviolet absorption of AlN nanowires array as a sensors was investigated and calculated with the first principle.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31670664

RESUMO

Category-specific 3D object shape models have greatly boosted the recent advances in object detection, recognition and segmentation. However, even the most advanced approach for learning 3D object shapes still requires heavy manual annotations on large-scale 2D images. In particular, annotating figure-ground segmentation is unbearably labor-intensive and time-consuming. To alleviate the costs of such manual annotations, we make an effort to learn category-specific 3D shape models by using weakly-labeled 2D images, where only object categories and keypoints are annotated. By exploring the underlying relationship between two tasks: object segmentation and category-specific 3D shape reconstruction, we propose a novel weakly-supervised learning framework to jointly address these two tasks and collaborate them to boost the final performance of the learned 3D shape models. Moreover, learning without using figure-ground segmentation leads to ambiguous solutions. To this end, we develop the confidence weighting schemes in the viewpoint estimation and 3D shape learning procedure. These schemes effectively reduce the confusion caused by the noisy data and thus increase the chances for obtaining more reliable 3D object shapes. Comprehensive experiments on the challenging PASCAL VOC benchmark show that our framework achieves comparable performance of the state-of-the-art methods that use expensive manual segmentation annotations.

5.
Neurobiol Dis ; 134: 104648, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31676238

RESUMO

Accumulation of DNA damage has been detected in the spinal cord of patients as well as in the G93A mouse model of amyotrophic lateral sclerosis (ALS). Wild-type p53-induced phosphatase 1 (Wip1) is a p53-inducible serine/threonine phosphatase that terminates DNA-damage responses via dephosphorylation of DNA-damage response proteins, namely ataxia-telangiectasia mutated (ATM) kinase, checkpoint kinase 2, and p53, thus enhancing cell proliferation. However, the role of Wip1, DNA-damage responses, and their interaction in ALS development remains to be elucidated. Here, we showed that Wip1 expression levels were substantially decreased in ALS motor neurons compared with wild-type controls both in vivo and in vitro. The DNA-damage response was activated in superoxide dismutase 1 (SOD1) G93A-transfected cells. However, increased expression of Wip1 improved cell viability and inhibited the DNA-damage response in mutated SOD1G93A cells. Further studies demonstrated that decreased Wip1 expression reduced cell viability and further activated the DNA-damage response in chronic H2O2-treated NSC34 cells. In contrast, Wip1 promoted cell survival and suppressed DNA damage-induced apoptosis during persistent DNA damage conditions. Over-expression of Wip1 in the central nervous system (CNS) can delay the onset of disease symptoms, extended the survival, decreased MN loss improved motor function and inhibit the DNA-damage response in SOD1 G93A mice. Furthermore, homeodomain-interacting protein kinase 2 (HIPK2) promoted the degradation of Wip1 via the ubiquitin-proteasome system during chronic stress. These findings indicate that persistent accumulation of DNA damage and subsequent chronic activation of the downstream DNA damage-response ATM and p53 pro-apoptotic signaling pathways may trigger neuronal dysfunction and neuronal death in ALS. Wip1 may play a protective role by targeting the DNA-damage response in ALS motor neurons. Importantly, these findings provide a novel direction for therapeutic options for patients with ALS.

6.
J Inorg Biochem ; 203: 110909, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31689591

RESUMO

Glioma stem cells (GSCs) are thought to be responsible for the recurrence and invasion of glioblastoma multiform (GBM), which have been evaluated and exploited as the therapeutic target for GBM. Cyclometalated iridium(III) complexes have been demonstrated as the potential anticancer agents, however, their antitumor efficacies against GSCs are still unknown. Herein, we investigated the antitumor activity of two cyclometalated iridium(III) complexes [Ir(ppy)2L](PF6) (Ir1) and [Ir(thpy)2L](PF6) (Ir2) (ppy = 2-phenylpyridine, thpy = 2-(2-thienyl)pyridine and L = 4,4'-Bis(hydroxymethyl)-2,2'-bipyridine) against GSCs. The results clearly indicate that Ir1 and Ir2 kill GSCs selectively with IC50 values ranging from 5.26-9.05 µM. Further mechanism research display that Ir1 and Ir2 can suppress the proliferation of GSCs, penetrate into GSCs efficiently, localize to mitochondria, and induce mitochondria-mediated apoptosis, including the loss of mitochondrial membrane (MMP), elevation of intracellular reactive oxygen species (ROS) and caspases activation. Moreover, Ir1 and Ir2 can destroy the GSCs self-renewal and unlimited proliferation capacity by affecting the GSCs colony formation. According our knowledge, this is the first study to investigate the anti-GSCs properties of cyclometalated iridium(III) complexes.

7.
Nat Commun ; 10(1): 5334, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767869

RESUMO

Protein products of the regenerating islet-derived (REG) gene family are important regulators of many cellular processes. Here we functionally characterise a non-protein coding product of the family, the long noncoding RNA (lncRNA) REG1CP that is transcribed from a DNA fragment at the family locus previously thought to be a pseudogene. REG1CP forms an RNA-DNA triplex with a homopurine stretch at the distal promoter of the REG3A gene, through which the DNA helicase FANCJ is tethered to the core promoter of REG3A where it unwinds double stranded DNA and facilitates a permissive state for glucocorticoid receptor α (GRα)-mediated REG3A transcription. As such, REG1CP promotes cancer cell proliferation and tumorigenicity and its upregulation is associated with poor outcome of patients. REG1CP is also transcriptionally inducible by GRα, indicative of feedforward regulation. These results reveal the function and regulation of REG1CP and suggest that REG1CP may constitute a target for cancer treatment.

8.
Nat Commun ; 10(1): 5230, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745089

RESUMO

The Hengduan Mountains (HDM) biodiversity hotspot exhibits exceptional alpine plant diversity. Here, we investigate factors driving intraspecific divergence within a HDM alpine species Salix brachista (Cushion willow), a common component of subnival assemblages. We produce a high-quality genome assembly for this species and characterize its genetic diversity, population structure and pattern of evolution by resequencing individuals collected across its distribution. We detect population divergence that has been shaped by a landscape of isolated sky island-like habitats displaying strong environmental heterogeneity across elevational gradients, combined with population size fluctuations that have occurred since approximately the late Miocene. These factors are likely important drivers of intraspecific divergence within Cushion willow and possibly other alpine plants with a similar distribution. Since intraspecific divergence is often the first step toward speciation, the same factors can be important contributors to the high alpine species diversity in the HDM.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31738501

RESUMO

How to prevent the agglomeration of nanoparticles in nanocomposites remains a key challenge. Using nanometer suspension as a doping agent provides an effective approach to solve this challenge. A new technique that consists of chemical coprecipitation, ball milling and sedimentation separation metheds was developed for preparing hard magnetic M-type BaFe12O19 nanometer suspension. The single phase BaFe12O19 nanoparticles dispersed uniformly in alcohol have been prepared by this new technique. Magnetic nanocomposite thermoelectric materials with a homogeneous dispersion of BaFe12O19 nanoparticles were prepared through a combination process of an ultrasonic mixing of BaFe12O19 nanometer suspension and In-filled CoSb3 thermoelectric matrix material and spark plasma sintering. The microstructure analysis of magnetic nanocomposite thermoelectric materials confirmed that using the nanometer suspension as a doping agent is an effective way to solve the agglomeration phenomenon of nanoparticles in nanocomposites. In addition, the decline of thermoelectric performance in the high temperature intrinsic excitation region of In-filled CoSb3 can be effectively suppressed by the magnetic phase transition of BaFe12O19 nanoparticles dried by nanometer suspension from ferromagnetism to paramagnetism. It is also confirmed that using the BaFe12O19 nanometer suspension as a thermoelectric performance enhancer is an effective way to solve the challenging problem of performance deterioration of thermoelectric materials at high temperature.

10.
Chemosphere ; 242: 125159, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31677513

RESUMO

One of the main problems in treating high volumes of wastewater is the long startup time required aerobic granular sludge (AGS), and this issue significantly limits the broad application of advanced AGS technology. To promote rapid AGS formation in the startup phase, a method was developed involving the recovery and natural drying of effluent sludge prior to feeding it back into the sequencing batch reactor (SBR). An analysis of the process shows that supplemented naturally dried sludge swiftly promoted sludge aggregation and granular sludge formation in the reactor, and feeding the SBR with naturally dried sludge aggregates (1.75 ±â€¯0.05 g/L seven times) significantly shortened the granulation time in the startup phase by 14 days. In addition, MLSS, SVI30, SVI30/SVI5, and the average granule size of AGS in the reactor were maintained at 4.66 g/L, 47.4 mL/g, 0.93, and 2.8 mm, respectively. When fed back into the bioreactor, the aggregates acted as nuclei/carriers in the rapid granulation and played a significant role in rendering the SBR operation stable. This approach could be used to eliminate the random granules aggregation-disintegration mechanism that occurs in the initial stage of AGS formation. The study results reveal that the removal rate of COD and NH4+-N were above 95% and 96%, respectively. Furthermore, this approach requires less energy and significantly reduces the amount of sludge produced (as the effluent sludge is reused).

11.
Clin Rheumatol ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713733

RESUMO

OBJECTIVE: To assess the efficacy and safety of the Chinese herb Tripterygium wilfordii Hook F (TwHF) for the treatment of systemic sclerosis-associated interstitial lung disease (SSc-ILD). METHODS: SSc-ILD patients who were regularly treated for more than 1 year and were currently taking a stable dose of TwHF (40-60 mg/day) or CYC (100 mg/day) were selected from the EUSTAR database of Peking Union Medical College Hospital. The efficacy of treatments was assessed by the change in pulmonary function, including the forced vital capacity (FVC) and the percentage of predicted FVC (FVC pred%). RESULTS: Among the 431 patients diagnosed with SSc-ILD, 76 fulfilled the inclusion and exclusion criteria. Twenty eight patients received TwHF monotherapy, while 48 received oral CYC monotherapy. Baseline data prior to treatment did not differ significantly between the two groups. After 1 year of treatment, significant improvements in the FVC and FVC pred% were seen in both groups (P < 0.05) and the magnitude of improvement was comparable (P = 0.93). However, TwHF was only found to be effective in improving FVC and FVC pred% when administered as a maintenance therapy, but not as an induction therapy. No severe adverse events were seen in either group. Leucopenia occurred more often in the CYC group compared to the TwHF group (P = 0.034). CONCLUSION: TwHF may be considered as a potential alternative drug for SSc-ILD patients, especially as a maintenance therapy. A prospective randomized controlled trial is necessary to further confirm these results.Key Points• This is the first clinical study of Tripterygium wilfordii Hook F (TwHF) in the treatment of SSc-ILD, providing a novel therapeutic option for SSc-ILD.• TwHF shows a comparable therapeutic efficacy to CYC when treating SSc-ILD.• TwHF has unique therapeutic advantages considering the balance of economy and safety and may be a good potential choice for maintenance therapy.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31680161

RESUMO

OBJECTIVES: Racial factors play a significant role in SSc. We evaluated differences in SSc presentations between white patients (WP), Asian patients (AP) and black patients (BP) and analysed the effects of geographical locations. METHODS: SSc characteristics of patients from the EUSTAR cohort were cross-sectionally compared across racial groups using survival and multiple logistic regression analyses. RESULTS: The study included 9162 WP, 341 AP and 181 BP. AP developed the first non-RP feature faster than WP but slower than BP. AP were less frequently anti-centromere (ACA; odds ratio (OR) = 0.4, P < 0.001) and more frequently anti-topoisomerase-I autoantibodies (ATA) positive (OR = 1.2, P = 0.068), while BP were less likely to be ACA and ATA positive than were WP [OR(ACA) = 0.3, P < 0.001; OR(ATA) = 0.5, P = 0.020]. AP had less often (OR = 0.7, P = 0.06) and BP more often (OR = 2.7, P < 0.001) diffuse skin involvement than had WP. AP and BP were more likely to have pulmonary hypertension [OR(AP) = 2.6, P < 0.001; OR(BP) = 2.7, P = 0.03 vs WP] and a reduced forced vital capacity [OR(AP) = 2.5, P < 0.001; OR(BP) = 2.4, P < 0.004] than were WP. AP more often had an impaired diffusing capacity of the lung than had BP and WP [OR(AP vs BP) = 1.9, P = 0.038; OR(AP vs WP) = 2.4, P < 0.001]. After RP onset, AP and BP had a higher hazard to die than had WP [hazard ratio (HR) (AP) = 1.6, P = 0.011; HR(BP) = 2.1, P < 0.001]. CONCLUSION: Compared with WP, and mostly independent of geographical location, AP have a faster and earlier disease onset with high prevalences of ATA, pulmonary hypertension and forced vital capacity impairment and higher mortality. BP had the fastest disease onset, a high prevalence of diffuse skin involvement and nominally the highest mortality.

13.
Drug Des Devel Ther ; 13: 2873-2886, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695321

RESUMO

Purpose: Pulmonary fibrosis (PF) is a common clinical disease, which results in serious respiratory impairment. Xin Jia Xuan Bai Cheng Qi Decoction (XJXBCQ) is a traditional prescription commonly used in treating lung diseases. We investigate the effect of XJXBCQ against PF and its mechanism via the regulation of TGF-ß1/Smad in vitro and in vivo. Materials and methods: XJXBCQ was first extracted and probed for chemical characterization. An PF model in vitro and in vivo was established in rats and in MRC-5 cells. In bleomycin (BLM)-induced rats model, lung function such as peak expiratory flow (PEF), minute ventilation (MV) and hydroxyproline (HYP) were measured; histopathological changes of lung tissue and TGF-ß1 in peripheral blood of rats were detected. TGF-ß receptor, Smad2 and its phosphorylation expression were tested by Western blot assay in rats model. Then the effects of XJXBCQ on TGF-ß1/Smad signal pathway were assessed by Western blot analysis in vitro, and IL-17A and IL-25 levels were evaluated by ELISA in vivo. Results: Our results showed that XJXBCQ significantly enhanced the lung functions, such as PEF, MV and HYP, by reducing the expression level of lung inflammatory cytokine and the content and fibrosis of lung collagen. Moreover, XJXBCQ effectively inhibited TGF-ß1, Smad2 and its phosphorylation expression, and the activation of Smad7 in vitro and in vivo. Furthermore, XJXBCQ had an inhibitory effect on the α-smooth muscle actin (α-SMA) and fibronectin (Fn) in vitro and downregulated IL-17A and IL-25 by inhibiting the activation of TGF-ß1/Smad signaling pathway in vitro and in vivo. Further, XJXBCQ effectively inhibitied ventilation volume and peak expiratory content remodeling and hydroxyproline content through inhibition of TGF-ßRⅡ, Smad2 and its phosphorylation expression, and activation of Smad7 in vivo. Conclusion: XJXBCQ extract had an anti-PF effect in vitro and in vivo, which could be attributed to the inhibition of the expression of p-Smad2 and increase in the expression of Smad7 by regulating the TGF-ß1/Smad activity.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31722171

RESUMO

Dichromate is a widespread contaminant in wastewater, threatening the health of humans and other organisms. Therefore, effective detection and removal of dichromate from water is of great significance. Herein, a tetraphenylethylene functionalized cationic organic network (CON-LDU2) was constructed via a facile quaternization reaction. CON-LDU2 was successfully integrated with both detection and removal functionalities toward dichromate. On the one hand, benefiting from the strong fluorescence, CON-LDU2 was employed as a chemosensor, it could efficiently and selectively probe Cr2O72- in water with "turn-off" fluorescent response. On the other hand, the cationic skeleton and free anions inside framework make CON-LDU2 an excellent adsorbent for Cr2O72-, it could capture Cr2O72- from water with rapid kinetics and high capacity. The kinetic constant for adsorption of Cr2O72- can reach up to 1.784 g mg-1 min-1, while the capacity is determined as 325 mg g-1. Furthermore, CON-LDU2 displayed good recyclability and can be reused for at least 5 cycles. Therefore, CON-LDU2 can serve as an ideal candidate not only in detection but also in removal of Cr2O72- in water medium.

16.
Zhongguo Zhen Jiu ; 39(11): 1187-90, 2019 Nov 12.
Artigo em Chinês | MEDLINE | ID: mdl-31724355

RESUMO

Four controversial types of simplex reinforcing-reducing manipulation of acupuncture and their possible meanings were summarized to explore several key elements of reinforcing-reducing manipulation of acupuncture, in addition, the simplex reinforcing-reducing manipulation of acupuncture was classified by single factor. It is concluded that the definition of simplex reinforcing-reducing manipulation of acupuncture should try not to include other non-manipulative elements. According to single factor, it can be divided into: needle-oriented reinforcing-reducing manipulation, twisting reinforcing-reducing manipulation, lifting and interpolating reinforcing-reducing manipulation, fast and slow reinforcing-reducing manipulation, breathing reinforcing-reducing manipulation, opening and closing reinforcing-reducing manipulation. In addition, after considering the effect and principle of number reinforcing-reducing manipulation, it can be considered.


Assuntos
Terapia por Acupuntura , Pontos de Acupuntura , Terapia por Acupuntura/instrumentação , Terapia por Acupuntura/métodos , Humanos , Meridianos , Agulhas
17.
Artigo em Inglês | MEDLINE | ID: mdl-31767359

RESUMO

OBJECTIVE: To investigate a technical method for harvesting and using the descending branch of the lateral circumflex femoral artery (DLCFA) in coronary artery bypass grafting (CABG). METHODS: Between January 2017 and January 2019, 40 patients (36 in the planed selection group and 4 in the temporary decision group) with mean age of 49.1 ± 7.5 years received DLCFA as an arterial conduit in CABG. In all patients, the DLCFA was successfully harvested via an anterior thigh incision. Depending on the location of the target vessel, the DLCFA was used as a free graft or a composite graft. RESULTS: Of the 44 patients in the planned selection group, DLCFA harvesting was abandoned in 8 patients because computed tomographic angiography revealed anatomical variation or stenosis of the superficial femoral artery. Of the 5 patients in the temporary decision group, harvesting was abandoned in 1 because of short length and thin caliber. On an average, 3.7 ± 0.9 distal anastomoses were created during CABG, with no adverse effects. The length of the harvested DLCFA was 9.9 ± 1.7 cm, with an average proximal lumen diameter of 3.4 ± 0.7 mm. The DLCFA was used as a free graft in 26 patients and as a "Y"-shape composite graft in 14 patients. Total arterial CABG was performed in 75% of the patients. CONCLUSIONS: The DLCFA is an alternative conduit for CABG. It can be harvested easily and safely. However, preoperative computed tomographic angiography examination is necessary for the smooth application of the DLCFA, and an appropriate strategy for graft establishment should be considered.

18.
Chin J Integr Med ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31768870

RESUMO

OBJECTIVE: To investigate the effect of Chang'an II Decoction ( II ))-containing serum on intestinal epithelial barrier dysfunction in rats. METHODS: Tumor necrosis factor (TNF)-α-induced injury of Caco-2 monolayers were established as an inflammatory model of human intestinal epithelium. Caco-2 monolayers were treated with blank serum and Chang'an II Decoction-containing serum that obtained from the rats which were treated with distilled water and Chang'an II Decoction intragastrically at doses of 0.49, 0.98, 1.96 g/(kg·d) for 1 week, respectively. After preparation of containing serum, cells were divided into the normal group, the model group, the Chang'an II-H, M, and L groups (treated with 30 ng/mL TNF-α and medium plus 10% high, middle-, and low-doses Chang'an II serum, respectively). Epithelial barrier function was assessed by transepithelial electrical resistance (TER) and permeability of fluorescein isothiocyanate (FITC)-labeled dextran. Transmission electron microscopy was used to observe the ultrastructure of tight junctions (TJs). Immunofluorescence of zonula occludens-1 (ZO-1), claudin-1 and nuclear transcription factor-kappa p65 (NF-κ Bp65) were measured to determine the protein distribution. The mRNA expression of myosin light chain kinase (MLCK) was measured by real-time polymerase chain reaction. The expression levels of MLCK, myosin light chain (MLC) and p-MLC were determined by Western blot. RESULTS: Chang'an II Decoction-containing serum significantly attenuated the TER and paracellular permeability induced by TNF-α. It alleviated TNF-α-induced morphological alterations in TJ proteins. The increases in MLCK mRNA and MLCK, MLC and p-MLC protein expressions induced by TNF-α were significantly inhibited in the Chang'an II-H group. Additionally, Chang'an II Decoction significantly attenuated translocation of NF-κ Bp65 into the nucleus. CONCLUSION: High-dose Chang'an II-containing serum attenuates TNF-α-induced intestinal barrier dysfunction. The underlying mechanism may be involved in inhibiting the MLCK-MLC phosphorylation signaling pathway mediated by NF-κ Bp65.

19.
Analyst ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746822

RESUMO

Detecting atmospheric bioaerosols in a quantitative way is highly desirable for public health and safety. This work demonstrates that surface-enhanced Raman spectroscopy (SERS) is a simple and rapid analytical technique for the detection of atmospheric bioaerosols, on a Klarite substrate. For both simulated and ambient bioaerosols, this detection assay results in an increase in the enhancement factor of the Raman signal. We report a strong SERS signal generated by bioaerosols containing living Escherichia coli deposited on Klarite. Furthermore, we demonstrate that SERS mapping can be used to estimate the percentage of airborne, living Escherichia coli. Moreover, Klarite provides differently distinct SERS spectra at different bacterial growth phases, indicating its potential to identify changes occurring in the bacterial envelope. Finally, we applied SERS for the rapid detection of Escherichia coli in ambient bioaerosols without using time-consuming and laborious culture processes. Our results represent rapid, culture-free and label-free detection of airborne bacteria in the real-world environment.

20.
Inorg Chem ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31762286

RESUMO

Visible-light driven photoreactions using metal-organic frameworks (MOFs) as catalysts are promising with regard to their environmental friendly features such as the use of renewable and sustainable energy of visible light and potential catalyst recyclability. To develop potential heterogeneous photocatalysts, a family of three copper(II) coordination polymers bearing different Cu-O assemblies have been synthesized with the ligand 4,4'-disulfo-[1,1'-biphenyl]-2,2'-dicarboxylate acid (H4DSDC), namely, {[Cu7(DSDC)2(OH)6(H2O)10]·xH2O}n (1), {[Cu4(DSDC)(4,4'-bpy)2(OH)4]·2H2O}n (2), and {Cu2(DSDC)(phen)2(H2O)2}n (3) (4,4'-bpy = 4,4'-bipyridine and phen = 1,10-phenanthroline). Complex 1 represents a metal-organic framework featuring a NbO type topology constructed from the infinite linkage of heptanuclear [Cu7(µ3-OH)6(H2O)10]8+ clusters by deprotonated DSDC4- ligands, comprising one-dimensional hexagonal channels of a diameter around 11 Å that are filled with water molecules. The infinite waving {[Cu2(OH)2]2+}n ladderlike chains in complex 2 are bridged by DSDC4- and 4,4'-bpy ligands into a three-dimensional framework. A two-dimensional layered structure is formed in complex 3 due to the existence of terminal phenanthroline ligands. All of the coordination polymers 1-3 are able to catalyze the visible-light driven oxidation of alcohols at mild conditions using hydrogen peroxide as an oxidant, in which complex 1 demonstrates satisfactory efficiency. Significantly for this photoreaction catalyzed by 1, the extent of oxidation over aryl primary alcohols is fully controllable with time-resolved product selectivity, giving either corresponding aldehydes or carboxylate acids in good yields. It is also remarkable that the photocatalyst could be recovered almost quantitatively on completion of the catalytic cycle without any structure change, and could be recycled for catalytic use for at least five cycles with constant efficiency. This photocatalyst with time-resolved selectivity for different products may provide new insight into the design and development of novel catalytic systems.

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