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1.
J Viral Hepat ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32048386

RESUMO

Not all treatment-naïve patients receiving entecavir (ETV) or tenofovir disoproxil fumarate (TDF) therapy can achieve complete virological response, and many factors may be related with the outcome of partial virological response. This study aimed to determine whether the manner of drug administration affects the antiviral efficacy of ETV/TDF monotherapy. All eligible patients were divided into complete or partical response cohorts based on their virological response following 24-weeks therapy. Factors related with partial response were evaluated. Patients with partial response were further grouped depending on whether they later adjusted the manner of drug administration, and the antiviral efficacy was compared between the two groups during prolonged treatment. A total of 518 patients were enrolled. Suboptimal drug administration (OR 77.511, p =0.000), positive-HBeAg (OR 3.191, p =0.000) and ETV treatment (OR 2.537, p =0.001) were identified as independent risk factors for partial response. Among patients with partial response, 213 were in the adjusted group and 76 were in the unadjusted group. The percentages of patients with undetectable serum HBV DNA (78.9% vs 31.6%, p <0.001) and with normal ALT (88.7% vs 68.4%, p <0.001) were both higher in the adjusted group than that in unadjusted group following a further 6-months therapy. In conclusion, the manner of drug administration is an important factor influencing the efficacy of ETV/TDF therapy, and optimal drug administration manner can help to increase antiviral efficacy and rescue patients with partial response.

2.
J Mol Med (Berl) ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060588

RESUMO

AVE0991, a nonpeptide angiotensin-(1-7) mimic, has similar protective effects for cardiovascular system to Ang-(1-7). In this article, we aimed to explore the effects of AVE0991 and Ang-(1-7) on abdominal aortic aneurysm (AAA) induced by Ang II in apolipoprotein E knockout mice. The mice AAA model was established by Ang II infusion, and then mice received different treatment with saline, Ang II (1.44 mg/kg/day), different dose AVE0991 (0.58 or 1.16 µmol/kg/day), or Ang-(1-7) (400 ng/kg/min). The incidence of AAA was 76%, 48%, 28%, and 24% in the vehicle, the low-dose AVE0991, high-dose AVE0991, and the Ang-(1-7) group, respectively. In comparison with control group, AVE0991 and Ang-(1-7) treatment significantly increased smooth muscle cells and decreased macrophage accumulation, the expression levels of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor α (TNF-α), and the expression and activity of metalloproteinases 2 and 9 in mice AAA model or in human smooth muscle cells (hVSMCs). The therapeutic effects may be contributed to reduction of oxidative stress and downregulation of P38 and ERK1/2 signal pathways via Mas receptor activation, whereas the positive impacts were reversed by co-administration with the Mas antagonist A779 (400 ng/kg/min) and AVE0991 in Ang II-infused mice or in hVSMCs. Therefore, AVE0991 and Ang-(1-7) might be novel and promising interventions in the prevention and treatment of AAA. KEY MESSAGES: • AVE0991 dose-dependently inhibited Ang II-induced AAA formation in Apoe-/- mice. • Ang-(1-7) played the same protective role as high-dose AVE0991. • Inhibition of Mas receptor with A779 could reverse the protective effect of AVE0991. • The therapeutic effects may be contributed to reduction of oxidative stress and downregulation of P38 and ERK1/2 signal pathways via Mas receptor activation.

3.
FASEB J ; 34(1): 1345-1361, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914618

RESUMO

Cell morphology and tissue integrity are essential for embryogenesis. Caveolins are membrane proteins that induce the formation of surface pits called caveolae that serve as membrane reservoirs for cell and tissue protection during development. In vertebrates, caveolin 1 (Cav1) and caveolin 3 (Cav3) are required for caveola formation. However, the formation of caveola and the function of caveolins in invertebrates are largely unknown. In this study, three caveolins, Cav-a, Cav-b, and CavY, are identified in the genome of the invertebrate chordate Ciona spp. Based on phylogenetic analysis, Cav-a is found to be closely related to the vertebrate Cav1 and Cav3. In situ hybridization shows that Cav-a is expressed in Ciona embryonic notochord and muscle. Cell-free experiments, model cell culture systems, and in vivo experiments demonstrate that Ciona Cav-a has the ability to induce membrane curvature at the plasma membrane. Knockdown of Cav-a in Ciona embryos causes loss of invaginations in the plasma membrane and results in the failure of notochord elongation and lumenogenesis. Expression of a dominant-negative Cav-a point mutation causes cells to change shape and become displaced from the muscle and notochord to disrupt tissue integrity. Furthermore, we demonstrate that Cav-a vesicles show polarized trafficking and localize at the luminal membrane during notochord lumenogenesis. Taken together, these results show that the invertebrate chordate caveolin from Ciona plays crucial roles in tissue integrity and morphology by inducing membrane curvature and intracellular vesicle trafficking during embryogenesis.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31929375

RESUMO

The purpose of this study was to evaluate the relationship between radiation dose and noise level on various coronary calcium scoring protocols between 64-multidetector computed tomography (MDCT) and 320-MDCT. The cardiac QRM phantoms (1 small size and 1 medium size) were used in this study. Lower-dose imaging protocols were proposed for optimization with the parameters of 120 kVp and 10 mAs for small-size phantom (0.336 mSv) in 64-MDCT imaging and small-size phantom (0.2 mSv) in 320-MDCT case, and 120 kVp and 80 mAs for medium-size phantom (2.73 mSv) in 64-MDCT imaging and medium-size phantom (1.58 mSv) in 320-MDCT case. Our results suggest that people can apply lower-dose protocols in the clinical use for early diagnosis of coronary disease without sacrificing diagnostic accuracy.

5.
Hum Gene Ther ; 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992084

RESUMO

The pro-renin receptor (PRR), as an important novel component of the renin-angiotensin system, has multifunction yet not completely known. In this study, we aimed to explore the effect of PRR on the formation of Ang II-induced abdominal aortic aneurysm (AAA) in apolipoprotein E-knockout mice. We used Ang II (1.44 mg/kg/day) infusion to induce AAA, then mice received different treatment with saline, telmisartan, no treatment, Ad-EGFP, Ad-PRR, or Ad-PRR plus telmisartan. The incidence of AAA was 35%, 60%, 65%, 90%, and 55% in the Telmisartan, Vehicle, Ad-EGFP, Ad-PRR, and Ad- PRR+Telmisartan groups, respectively. Compared with the Vehicle and Ad-EGFP groups, PRR overexpression markedly increased macrophage infiltration; levels of proinflammatory cytokines, including MCP-1 and TNF-α; the expression and activity of MMP2 and MMP9; NOX2 and NOX4 protein and mRNA expression; NADPH oxidase activity; ERK and P38MAPK expression; but decreased smooth muscle cells content in AAA. However, telmisartan reversed the adverse effects of PRR. In addition, ERK inhibitor PD98059 eliminated the acceleration of Ang II-induced AAA formation by PRR and co-administration of telmisartan and PD98059 further abolished the adverse effects of PRR on Ang II-induced AAA formation. Thus, PRR plays an important role in the pathological development of AAA via both Ang II-dependent and -independent activation of ERK pathways and inhibition of PRR activation may be a promising approach to the treatment of AAA.

6.
J Cell Mol Med ; 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31970902

RESUMO

Macrophage activation participates in the pathogenesis of pulmonary inflammation. As a coenzyme, vitamin B6 (VitB6) is mainly involved in the metabolism of amino acids, nucleic acids, glycogen and lipids. We have previously reported that activation of AMP-activated protein kinase (AMPK) produces anti-inflammatory effects both in vitro and in vivo. Whether VitB6 via AMPK activation prevents pulmonary inflammation remains unknown. The model of acute pneumonia was induced by injecting mice with lipopolysaccharide (LPS). The inflammation was determined by measuring the levels of interleukin-1 beta (IL-1ß), IL-6 and tumour necrosis factor alpha (TNF-α) using real time PCR, ELISA and immunohistochemistry. Exposure of cultured primary macrophages to VitB6 increased AMP-activated protein kinase (AMPK) Thr172 phosphorylation in a time/dose-dependent manner, which was inhibited by compound C. VitB6 downregulated the inflammatory gene expressions including IL-1ß, IL-6 and TNF-α in macrophages challenged with LPS. These effects of VitB6 were mirrored by AMPK activator 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR). However, VitB6 was unable to inhibit LPS-induced macrophage activation if AMPK was in deficient through siRNA-mediated approaches. Further, the anti-inflammatory effects produced by VitB6 or AICAR in LPS-treated macrophages were abolished in DOK3 gene knockout (DOK3-/- ) macrophages, but were enhanced in macrophages if DOK3 was overexpressed. In vivo studies indicated that administration of VitB6 remarkably inhibited LPS-induced both systemic inflammation and acute pneumonia in wild-type mice, but not in DOK3-/- mice. VitB6 prevents LPS-induced acute pulmonary inflammation in mice via the inhibition of macrophage activation.

7.
World Neurosurg ; 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31958591

RESUMO

BACKGROUND: Microvascular decompression (MVD) has been the most effective long-term surgical treatment of trigeminal neuralgia (TN). However, the risk factors for poor pain control after MVD are not fully understood. METHODS: A total of 184 patients with typical TN who had undergone MVD at our institution from January 3, 2008 to January 3, 2016 were enrolled in the present study. The data were collected from the electronic operative records and case notes and retrospectively analyzed. Patients were followed up at the outpatient department or by telephone at a minimum of 3 months and a maximum of 48 months postoperatively. RESULTS: Of the 184 patients enrolled in the present study, 72.3% had had freedom from pain after MVD and 27.7% had experienced poor pain control at the follow-up examinations (minimum, 3 months; maximum, 48 months). The risk factors for poor pain control after MVD using binary logistic regression and receiver operating characteristic curve analysis included younger age (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.82-0.99; P = 0.028; area under the curve [AUC], 0.774), poor preoperative pain control (Barrow Neurological Institute score >IV; OR, 52.03; 95% CI, 6.44-420.16; P < 0.001; AUC, 0.858), intraoperatively detected multivessel compression (OR, 2.49; 95% CI, 3.10-46.59, P < 0.001; AUC, 0.871). Furthermore, combined compression of the superior cerebellar artery and petrosal vein was an independent risk factor predicting a poor outcome after MVD (OR, 5.69; 95% CI, 33.78-2579.03; P < 0.001; AUC, 0.812). CONCLUSIONS: Younger patients with TN had worse long-term pain outcomes after MVD. The additional factors associated with postoperative recurrence included poor preoperative pain control (Barrow Neurological Institute score >IV) and multivessel compression. Furthermore, combined compression of the superior cerebellar artery and petrosal vein was associated with worse outcomes.

8.
J Med Virol ; 92(3): 302-308, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31609007

RESUMO

AIMS: The aim of this retrospective study was to compare the efficacy and safety of tenofovir disoproxil fumarate (TDF) monotherapy and TDF + entecavir (ETV) combination therapy for chronic hepatitis B (CHB) patients with the partial virological response (PVR) to ETV. METHODS: CHB patients with PVR to ETV were switched to TDF monotherapy or TDF + ETV combination therapy. The primary efficacy outcome was a virological response (VR), and the secondary efficacy outcomes were hepatitis B e antigen (HBeAg) seroconversion and alanine aminotransferase (ALT) normalization. The primary safety outcomes were changes in serum creatinine and serum phosphorus levels. RESULTS: A total of 143 patients were investigated, including 63 patients in the TDF monotherapy group and 80 patients in the TDF + ETV combination therapy group. Baseline demographics and clinical characteristics were comparable between groups. The median age of patients was 44.5 years, and 76.2% of them were male. The VR rate in TDF + ETV group was higher than that of the TDF group at 48 weeks (88.8% vs 71.4%; P = .009). At 48 weeks, the HBeAg seroconversion rate of TDF + ETV group was higher than that of the TDF group (30% vs 15.9%; P = .049). There was no significant difference in the proportion of patients with elevated ALT in the TDF group and TDF + ETV group at 48 weeks (9.5% vs 7.5%; P = .665). After adjusting the treatment regimen, serum creatinine levels increased slightly and serum phosphorus level decreased slightly in both groups. CONCLUSIONS: TDF + ETV combination therapy for 48 weeks had a higher VR rate than TDF monotherapy in CHB patients with PVR to ETV.

9.
Med Clin (Barc) ; 154(1): 7-12, 2020 Jan 10.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31133232

RESUMO

BACKGROUND: There is growing evidence that vitamin D is related to the development of a variety of diseases. The current study was performed to investigate the status of serum vitamin D distribution among adult Chinese people and reveal the influence of gender, age, seasonality and residential regions on serum vitamin D levels. METHOD: This cross-sectional study included 14,302 participants aged from 18 years old to 65 years old from six major cities in China. The basic demographic information and the levels of serum vitamin D (25(OH)D) and vitamin D3 (25(OH)D3) were collected from Jan 2, 2014 to Dec 25, 2017. RESULT: The prevalence of 25(OH)D3 concentration <30ng/mL reached up to 83%, in which the rate of vitamin D insufficiency (20-29ng/mL) was 32.7%, and vitamin D deficiency (10-19ng/mL) accounted for 41.9%, and vitamin D severe shortage (<10ng/mL) accounted for 8.4%. Women were more likely to have vitamin D3 deficiency and lower serum vitamin D3 concentration than men (both p<0.001). The mean concentration of serum 25(OH)D and 25(OH)D3 in summer and autumn were higher than that in spring and winter (p<0.001), and the mean concentration of serum 25(OH)D in people from Southern China was higher than that in people from other regions (p<0.001). Although the mean concentrations of serum 25(OH)D and 25(OH)D3 were both increased by age, the percentage of patients with serum 25(OH)D3 insufficiency was also increased. CONCLUSION: Serum vitamin D deficiency is very common in adults in China. The level of serum vitamin D may be associated with age, sex, seasonality and residential regions.

10.
Surg Endosc ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823047

RESUMO

BACKGROUND: Previous retrospective studies have shown that laparoscopic spleen-preserving D2 total gastrectomy (LSTG) for advanced upper third gastric cancer (AUTGC) is safe. However, all previous studies were underpowered. We therefore conducted a prospective, multicenter study to evaluate the technical safety and feasibility of LSTG for patients with AUTGC. METHODS: Patients diagnosed with AUTGC (cT2-4a, N-/+, M0) underwent LSTG at 19 institutions between September 2016 and October 2017 were included. The number of No. 10 lymph node (LN) dissections, metastasis rates, intraoperative and postoperative complications were investigated. RESULTS: A total of 251 patients were enrolled in the study, and 242 patients were eligible for the per protocol analysis. The average numbers of No. 10 LN dissections and metastases were 2.4 and 0.1, respectively. Eighteen patients (7.4%) had No. 10 LN metastases, and among patients with advanced gastric cancer, the rate of No. 10 LN metastasis was 8.1% (18/223). pN3 status was an independent risk factor for No. 10 LN metastasis. Intraoperative complications occurred in 7 patients, but no patients required conversion to open surgery or splenectomy. The overall postoperative complication rate was 13.6% (33/242). The major complication and mortality rates were 3.3% (8/242) and 0.4% (1/242), respectively. The number of retrieved No. 10 LNs, No. 10 LN metastasis and TNM stage had no significant influence on postoperative complication rates. CONCLUSION: LSTG for AUTGC was safe and effective when performed by very experienced surgeons, this technique could be used in patients who needed splenic hilar lymph node dissection.

11.
Mar Drugs ; 17(12)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795141

RESUMO

Marine ascidians are becoming important drug sources that provide abundant secondary metabolites with novel structures and high bioactivities. As one of the most chemically prolific marine animals, more than 1200 inspirational natural products, such as alkaloids, peptides, and polyketides, with intricate and novel chemical structures have been identified from ascidians. Some of them have been successfully developed as lead compounds or highly efficient drugs. Although numerous compounds that exist in ascidians have been structurally and functionally identified, their origins are not clear. Interestingly, growing evidence has shown that these natural products not only come from ascidians, but they also originate from symbiotic microbes. This review classifies the identified natural products from ascidians and the associated symbionts. Then, we discuss the diversity of ascidian symbiotic microbe communities, which synthesize diverse natural products that are beneficial for the hosts. Identification of the complex interactions between the symbiont and the host is a useful approach to discovering ways that direct the biosynthesis of novel bioactive compounds with pharmaceutical potentials.

12.
J Prosthet Dent ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31780108

RESUMO

A fully digital workflow for designing and manufacturing a splinted framework and a custom tray for the impression of multiple implants placed with guided surgery is described. This digital workflow protocol does not require extra visits after surgery to prepare for the definitive impression because of the use of preoperative digital implant planning data. As a result, it helps reduce laboratory procedures, chairside time, and treatment cost.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31765322

RESUMO

Auscultation of the heart is a widely studied technique, which requires precise hearing from practitioners as a means of distinguishing subtle differences in heart-beat rhythm. This technique is popular due to its non-invasive nature, and can be an early diagnosis aid for a range of cardiac conditions. Machine listening approaches can support this process, monitoring continuously and allowing for a representation of both mild and chronic heart conditions. Despite this potential, relevant databases and benchmark studies are scarce. In this paper, we introduce our publicly accessible database, the Heart Sounds Shenzhen Corpus (HSS), which was first released during the recent INTERSPEECH 2018 ComParE Heart Sound sub-challenge. Additionally, we provide a survey of machine learning work in the area of heart sound recognition, as well as a benchmark for HSS utilising standard acoustic features and machine learning models. At best our support vector machine with Log Mel features achieves 49.7% unweighted average recall on a three category task (normal, mild, moderate/severe).

14.
Front Psychol ; 10: 2186, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681062

RESUMO

Two studies were undertaken to investigate structural priming in Mandarin-speaking three-, four- and, six-year-old children using a Mandarin-specific alternation between an SVO construction and a ba-construction (SbaOV). Structural priming occurred either as a single prime or cumulatively when a block of multiple primes with the same structure is administered. The results of Study 1 find that these preschoolers exhibited structural priming effects of similar magnitudes with the SVO-ba alternation across three age groups. The results of Study 2 show that they exhibited cumulative structural priming effects of similar magnitudes when there is no delay vs. a 1-day delay between their comprehension of primes and their target descriptions. The results also indicate that the participants exhibited stronger cumulative structural priming than regular structural priming. Together, these results suggest that at the age of three, children can employ an abstract syntactic representation to adapt to input changes and this adaptation operates on an implicit learning mechanism.

15.
Schizophr Res ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31704157

RESUMO

The GABA deficit hypothesis remains one of the most compelling explanations for the information processing impairments in schizophrenia. However, much of the supportive evidence has been derived from post-mortem studies, whereas in vivo studies have largely yielded inconsistent results. We undertook this single voxel proton magnetic resonance (MRS) GABA study to test in a sample of recent onset patients the replicability of our prior finding of reduced early visual cortex GABA in schizophrenia. We also examined the possibility that antipsychotics could represent a significant confound by studying a small subsample of antipsychotic naïve subjects. 23 adults with recent onset schizophrenia and a demographically matched sample of 31 healthy control subjects underwent MRS using a MEGA PRESS sequence on a 3T MR scanner to measure GABA concentration in early visual cortex. To control for in-scanner head movement confounding the results, we quantified the amount of head movement during GABA scans to identify and exclude from analysis scans with excessive movement. Patients demonstrated significantly reduced GABA levels compared to control subjects, p = 0.029. GABA levels did not differ significantly between patients who were antipsychotic naïve (n = 7) and patients treated with antipsychotics. This replication in a recent onset sample suggest that diminished GABA in the visual cortex is a reliable finding, present in early phase of illness and not confounded by illness chronicity.

16.
Molecules ; 24(22)2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31726738

RESUMO

Indigo naturalis (IN) is a traditional Chinese medicine, named Qing-Dai, which is extracted from indigo plants and has been used to treat patients with inflammatory bowel disease (IBD) in China and Japan. Though there are notable effects of IN on colitis, the mechanisms remain elusive. Regarding the significance of alterations of intestinal flora related to IBD and the poor water solubility of the blue IN powder, we predicted that the protective action of IN on colitis may occur through modifying gut microbiota. To investigate the relationships of IN, colitis, and gut microbiomes, a dextran sulfate sodium (DSS)-induced mice colitis model was tested to explore the protective effects of IN on macroscopic colitis symptoms, the histopathological structure, inflammation cytokines, and gut microbiota, and their potential functions. Sulfasalazine (SASP) was used as the positive control. Firstly, because it was a mixture, the main chemical compositions of indigo and indirubin in IN were detected by ultra-performance liquid chromatography (UPLC). The clinical activity score (CAS), hematoxylin and eosin (H&E) staining results, and enzyme-linked immunosorbent assay (ELISA) results in this study showed that IN greatly improved the health conditions of the tested colitis mice, ameliorated the histopathological structure of the colon tissue, down-regulated pro-inflammatory cytokines, and up-regulated anti-inflammatory cytokines. The results of 16S rDNA sequences analysis with the Illumina MiSeq platform showed that IN could modulate the balance of gut microbiota, especially by down-regulating the relative quantity of Turicibacter and up-regulating the relative quantity of Peptococcus. The therapeutic effect of IN may be closely related to the anaerobic gram-positive bacteria of Turicibacter and Peptococcus. The inferred metagenomes from 16S data using PICRUSt demonstrated that decreased metabolic genes, such as through biosynthesis of siderophore group nonribosomal peptides, non-homologous end-joining, and glycosphingolipid biosynthesis of lacto and neolacto series, may maintain microbiota homeostasis during inflammation from IN treatment in DSS-induced colitis.

17.
Cancer Sci ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31710406

RESUMO

The present study was designed to evaluate the dynamic survival and recurrence of remnant gastric cancer (RGC) after radical resection and to provide a reference for the development of personalized follow-up strategies. A total of 298 patients were analyzed for their 3-year conditional overall survival (COS3), 3-year conditional disease-specific survival (CDSS3), corresponding recurrence and pattern changes, and associated risk factors. The 5-year overall survival (OS) and the 5-year disease-specific survival (DSS) of the entire cohort were 41.2% and 45.8%, respectively. The COS3 and CDDS3 of RGC patients who survived for 5 years were 84.0% and 89.8%, respectively. The conditional survival in patients with unfavorable prognostic characteristics showed greater growth over time than in those with favorable prognostic characteristics (eg, COS3, ≥T3: 46.4%-83.0%, Δ36.6% vs ≤T2: 82.4%-85.7%, Δ3.3%; P < 0.001). Most recurrences (93.5%) occurred in the first 3 years after surgery. The American Joint Committee on Cancer (AJCC) stage was the only factor that affected recurrence. Time-dependent Cox regression showed that for both OS and DSS, after 4 years of survival, the common prognostic factors that were initially judged lost their ability to predict survival (P > 0.05). Time-dependent logistic regression analysis showed that the AJCC stage independently affected recurrence within 2 years after surgery (P < 0.05). A postoperative follow-up model was developed for RGC patients. In conclusion, patients with RGC usually have a high likelihood of death or recurrence within 3 years after radical surgery. We developed a postoperative follow-up model for RGC patients of different stages, which may affect the design of future clinical trials.

18.
Sensors (Basel) ; 19(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683511

RESUMO

A simple and practical full-frame single-camera stereo-digital image correlation (stereo-DIC) technique for three-dimensional (3D) shape, displacement, and deformation measurements is proposed. The technique uses a compact X-cube prism-based color separation device and a color camera to capture images of blue and red colors from different optical paths, and then extracts the surface 3D shape and deformation information of a test sample by processing the captured two sub-channel color images using regular stereo-DIC algorithm. Compared with the existing full-frame single-camera stereo-DICs, the proposed one eliminates the need for a beam splitter and two bandpass filters to capture images, and offers more simple, compact, and easy-to-use optical arrangement. This novel single-camera stereo-DIC technique was validated by a series of baseline experiments involving 3D surface reconstructions, translation tests, and full-field deformation measurements, which provide a new flexible and practical avenue for measuring surface 3D shape and deformation, particularly in microscopic and high-speed applications.

19.
Nanoscale Res Lett ; 14(1): 331, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641875

RESUMO

In this paper, an anomalous spectral data of distributed Bragg reflector (DBR) quantum cascade lasers (QCLs) emitting around 7.6 µm is presented. The two-section DBR lasers, consisting of a gain section and an unpumped Bragg reflector, display an output power above 0.6 W in continuous wave (CW) mode at room temperature. The anomalous spectral data is defined as a longitudinal mode which moves toward shorter wavelengths with increasing temperature or injection current, which is unexpected. Although the longer wavelength modes are expected to start lasing when raising device temperature or injection current, occasional mode hops to a shorter wavelength are seen. These anomalous mode transitions are explained by means of modal analysis. The thermal-induced change of the refractive index implied by an increase in the temperature or injection current yields nearly periodic transitions between cavity modes.

20.
Nat Prod Res ; : 1-9, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31596143

RESUMO

Two new highly-oxygenated neo-clerodane diterpenoids, 3S-acetoxyl-mollotucin D dilactone ester (1) and 6S-crotoeurin C (2), and a new lupane-type triterpene, 16ß-hydroxyl-3ß-O-trans-coumaroyl-betulin (6), as well as three known analogues (3-5) were obtained from the leaves of Croton laui. The structures of the new compounds were determined by extensive spectroscopic methods, and their absolute configurations were determined by combination of single-crystal X-ray diffraction analysis, electronic circular dichroism (ECD) spectra, and literature data. Compounds 2 and 3 exhibited inhibitory activities of lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 macrophages with IC50 values of 1.2 and 1.6 µM, respectively. Additionally, compound 6 exhibited activity against Col205 and HepG2 cell lines with IC50 values of 12.9 and 17.7 µM, respectively.

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